| The list might contain errors. |
A
edit- Å -> angstrom
- AAO -> Anglo-Australian Observatory
- AAS -> American Astronomical Society
- AAT -> Anglo-Australian Telescope
- AAVSO -> American Association of Variable Star Observers
- A band
- Abell Catalogue
- Abell cluster
- Abell radius
- constant of aberration -> annual aberration
- optical aberration
- aberration of starlight
- ablation
- ablation age
- absolute magnitude
- 1
- 2
- absolute temperature -> thermodynamic temperature
- absolute zero
- absorption
- absorption coefficient
- absorption edge
- absorption line
- absorption nebula -> dark nebula
- absorption spectrum
- abundance -> abundance of elements
- Acamar
- acceleration of free fall
- accretion
- accretion disk
- ACE -> Advanced Composition Explorer
- Achernar
- Achilles
- achondrite
- achromatic
- achromatism
- A-class asteroid
- acronical
- Acrux -> Alpha Crucis
- active galactic nucleus
- active optics
- active prominence
- active region
- John Couch Adams
- Walter Sydney Adams
- Adams Ring
- adaptive optics
- Adhara
- adiabatic process
- Adonis
- Adrastea (moon)
- ADS -> Aitken Double Star Catalogue
- Advanced Composition Explorer
- ACE
- advance of perihelion
- advection
- aeon
- aerial -> antenna
- aerobraking
- aerolite -> stony meteorite
- aeronomy
- aerosol
- Ae star
- aether -> ether
- afocal
- afterglow
- AGB star -> asymptotic giant branch star
- Agena -> Hadar -> Beta Centauri
- agglutinate
- AGILE
- AGK
- AGN -> active galactic nucleus
- Ahnighito meteorite -> Cape York meteorite
- airglow
- airmass
- air shower -> cosmic-ray shower
- George Biddell Airy
- Airy disk
- Robert Grant Aitken
- Aitken Double Star Catalogue
- AI Velorum star
- AJ -> Astronomical Journal
- Akari
- Albategnius -> al-Battani
- al-Battani -> Battani
- albedo
- albedo feature
- Albireo
- Alcor
- Alcyone
- Aldebaran
- Alderamin
- Alexandra family
- ALEXIS
- Hannes Olof Gösta Alfvén
- Alfvén surface
- Alfvén wave
- Algenib
- Algieba
- Algol
- Algol star
- Algonquin Radio Observatory
- Alhena
- aliasing
- alidade
- Alioth
- Alkaid
- Allegheny Observatory
- Allende meteorite
- Allen Telescope Array
- all-sky camera
- ALMA -> Atacama Large Millimeter Array
- Almaak
- Almagest
- almanac
- almucantar
- Alnair
- Alnath
- Alnilam
- Alnitak
- α -> right ascension
- Alpha Capricornid meteors
- Alpha Centauri
- Alpha Crucis
- Alpha Cygnid meteors
- Alpha Cygni star
- alpha particle
- Alphard
- Alpha Scorpiid meteors
- Alpha2 Canum Venaticorum star
- Alphekka
- Alpheratz
- Alrescha
- Alshain
- al-Sufi -> Sufi
- Altair
- altazimuth mounting
- altitude
- al-Tusi -> Tusi
- aluminizing
- Amalthea
- Viktor Amazaspovich Ambartsumian
- ambipolar diffusion
- AM Canum Venaticorum star
- American Association of Variable Star Observers
- American Astronomical Society
- Ames Research Center
- AM Herculis star
- Amor group
- amplitude
- 1
- 2
- Am star
- anaemic spiral galaxy
- analemma
- Ananke
- anastigmatic
- Anaxagoras
- Anaximander
- Andromeda
- Andromeda Galaxy
- Andromedid meteors
- Anglo-Australian Observatory
- Anglo-Australian Telescope
- Anders Jonas Ångström
- angstrom
- angular acceleration
- angular diameter
- angular distance -> angular separation
- angular momentum
- angular resolution
- angular separation
- angular velocity
- anisotropy
- Ankaa
- annealing
- annual aberration
- annual equation
- annual inequality -> annual equation
- annual parallax
- annual variation
- annular eclipse
- anomalistic month
- anomalistic year
- anomalous Cepheid
- anomalous iron
- anomaly
- anorthosite
- ANS -> Astronomical Netherlands Satellite
- ansa
- ansae
- antapex -> solar apex
- Antares
- antenna
- Antennae
- antenna pattern
- antenna temperature
- anthelion
- anthelion radiant
- anthropic principle
- anticentre -> galactic anticentre
- anti-dwarf nova
- antimatter
- antitail
- Antlia
- Eugène Michael Antoniadi
- Antoniadi scale
- Antu
- ap-
- apo-
- Apache Point Observatory
- apastron
- aperture
- aperture efficiency
- aperture ratio
- aperture synthesis
- APEX -> Atacama Pathfinder Experiment
- apex -> solar apex
- aphelion
- Aphrodite Terra
- ApJ -> Astrophysical Journal
- aplanatic
- apoapsis
- apocentre
- apochromatic
- apodization
- apogee
- apohele
- Apollo group
- Apollonius of Perga
- Apollo project
- apparent diameter -> angular diameter
- apparent magnitude
- apparent noon
- apparent place
- apparent retrogression
- apparent sidereal time
- apparent solar time
- apparition
- appulse
- apse -> apsides
- apsis -> apsides
- apsidal motion
- apsides
- Ap star
- Apus
- Aquarid meteors
- Aquarius
- aqueous alteration
- Aquila
- Ara
- arachnoid
- François Arago
- Dominique François Jean Arago
- Arago ring
- arc
- archaeoastronomy
- arch filament system
- arc minute -> minute of arc
- arcmin -> minute of arc
- arc second -> second of arc
- arcsec -> second of arc
- Arcturus
- arcus
- area photometer
- Arecibo Observatory
- Comet Arend–Roland (C/1956 R1)
- areo-
- Friedrich Wilhelm August Argelander
- Argelander step method
- Argo Navis
- argon–potassium method -> potassium–argon method
- argument of perihelion
- Argyre Planitia
- Ariel
- Ariel satellites
- Aries
- first point of Aries
- Aristarchos Telescope
- Aristarchus of Samos
- Aristotle
- Arizona meteor crater -> meteor crater
- Arizona Radio Observatory
- ARO
- AR Lacertae star
- armillary sphere
- arm population
- Arneb
- array
- 1
- 2
- artificial satellite
- ASCA
- ascending node
- Asclepius
- ashen light
- ASP -> Astronomical Society of the Pacific
- aspect
- aspheric
- stellar association
- Association of Universities for Research in Astronomy
- AURA
- A star
- asterism
- asteroid
- asteroid belt
- asteroseismology
- asthenosphere
- astigmatism
- Astraea
- astration
- astrobiology
- astrobleme
- astrochemistry
- astrodynamics
- astrograph
- Astrographic Catalogue
- astrolabe
- astrology
- astrometric binary
- astrometry
- astronavigation
- Astronomer Royal
- Astronomer Royal for Scotland
- The Astronomical Almanac
- Astronomical Journal
- AJ
- Astronomical Netherlands Satellite
- ANS
- Astronomical Society of the Pacific
- ASP
- astronomical triangle
- astronomical twilight
- astronomical unit
- AU
- astronomy
- Astronomy and Astrophysics
- A&A -> Astronomy and Astrophysics
- astrophotography
- Astrophysical Journal
- astrophysics
- ASTROSAT
- astrum
- Asuka -> ASCA
- asymptotic giant branch star
- AGB star
- Atacama Large Millimeter Array
- ALMA
- Atacama Pathfinder Experiment
- APEX
- ataxite
- Aten group
- Atlas
- atmosphere
- atmospheric extinction
- atmospheric refraction
- atmospheric scattering -> atmospheric extinction -> Mie scattering -> Rayleigh scattering
- atmospheric window
- ATNF -> Australia Telescope National Facility
- atom
- atomic clock
- atomic time
- Atria
- attenuation
- 1
- 2
- AU -> astronomical unit
- aubrite
- Auger shower -> cosmic-ray shower
- augmentation
- AURA -> Association of Universities for Research in Astronomy
- Auriga
- Aurora programme
- aurora
- auroral oval
- auroral substorm -> substorm
- Australia Telescope National Facility
- ATNF
- australite
- autocorrelation
- autocorrelator
- autoguider
- autoionization
- autumnal equinox -> equinox
- averted vision
- Avior
- axion
- optical axis
- axis of rotation
- azimuth
- Azophi -> al-Sufi
B
edit- BAA -> British Astronomical Association
- Wilhelm Heinrich Walter Baade
- Walter Baade
- Baade's Window
- Baade–Wesselink method
- Harold Delos Babcock
- Horace Welcome Babcock
- background noise
- background radiation
- backscattering
- Bailey type
- Francis Baily
- Baily's beads
- Baker–Schmidt telescope
- Baldwin effect
- Balmer limit
- Balmer lines -> Balmer series
- Balmer series
- band
- bandpass filter
- bandwidth
- bar
- barium star
- Barlow lens
- Edward Emerson Barnard
- Barnard's Loop
- Barnard's Star
- barn-door mount -> Scotch mount
- Barnes–Evans relationship
- barred spiral galaxy
- barrel distortion
- Barringer Crater -> meteor crater
- barycentre
- Barycentric Celestial Reference System
- barycentric coordinates
- Barycentric Coordinate Time
- Barycentric Dynamical Time
- baryon
- baryon star
- basalt
- basaltic achondrite
- baseline
- impact basin
- Muammad ibn Jabir al-Battani
- Ba II star -> barium star
- Bautz–Morgan class
- Johann Bayer
- Bayer letters
- B band
- B-class asteroid
- BCRS -> Barycentric Celestial Reference System
- BD -> Bonner Durchmusterung
- Beagle
- beam
- beaming
- beamwidth
- beat Cepheid
- Becklin–Neugebauer Object (BN Object)
- Becrux -> Beta Crucis
- bediasite
- Beehive Cluster -> Praesepe
- Belinda
- Bellatrix
- Susan Jocelyn Bell Burnell
- Jocelyn Bell Burnell
- Belt of Orion
- Benetnasch -> Alkaid
- Comet Bennett (C/1969 Y1)
- bent-pillar mounting
- BepiColombo
- BeppoSAX
- Berkeley–Illinois–Maryland Association Array (BIMA Array)
- Friedrich Wilhelm Bessel
- Besselian day numbers
- Besselian elements
- Besselian epoch
- Besselian year
- Be star
- B(e) star
- Beta Canis Majoris star -> Beta Cephei star
- Beta Cephei star
- Beta Crucis
- beta decay
- Beta Lyrae star
- beta particle
- Beta Persei star -> Algol star
- Beta Pictoris
- Beta Regio
- Beta Taurid meteors
- Betelgeuse
- Hans Albrecht Bethe
- Bethe–Weizsäcker cycle -> carbon–nitrogen cycle
- Bianca
- Bianchi cosmology
- biconcave lens
- biconvex lens
- Comet 3D/Biela
- Bielid meteors -> Andromedid meteors
- Big Bang theory
- Big Bear Solar Observatory
- Big Crunch
- Big Dipper
- billitonite
- BIMA Array
- binary galaxy
- binary pulsar
- binary star
- binding energy
- binoculars
- Jean-Baptiste Biot
- bipolar group
- bipolar nebula
- bipolar outflow
- birefringent filter
- Birmingham Solar Oscillations Network
- BiSON -> Birmingham Solar Oscillations Network
- black body
- black-body radiation
- black drop
- black dwarf
- Black Eye Galaxy
- black hole
- Black Widow Pulsar -> binary pulsar
- blazar
- Blaze Star
- Blazhko effect
- BL Herculis star
- blink comparator
- Blinking Planetary
- BL Lacertae object
- BL Lac object
- bloomed lens
- blooming
- 1
- 2
- blue clearing
- blue compact dwarf galaxy
- blue giant
- blue Moon
- 1
- 2
- Blue Planetary
- blue populous cluster -> Large Magellanic Cloud
- blueshift
- blue straggler
- B magnitude
- BN Object -> Becklin–Neugebauer Object
- Johann Elert Bode
- Bode's law
- Bartholomeus Jan Bok
- Bartholomeus 'Bart' Jan Bok
- Bok globule -> globule
- bolide
- bolometer
- bolometric correction
- bolometric magnitude
- Boltzmann constant
- George Phillips Bond
- William Cranch Bond
- Bond albedo
- Hermann Bondi
- Bonner Durchmusterung
- Boötes
- boson
- Boss General Catalogue
- GC
- boundary layer
- bound–bound transition
- bound–free transition
- Bouwers telescope
- Ira Sprague Bowen
- Bowen fluorescence
- bow shock
- Bp star
- Brackett series
- James Bradley
- Bragg crystal spectrometer
- Tycho Brahe
- Brans–Dicke theory
- breccia
- bremsstrahlung
- bridge (astronomy)
- bright nebula
- brightness temperature
- Bright Star Catalogue
- British Astronomical Association
- broad-band photometry
- Brocchi's Cluster
- Comet 16P/Brooks 2 -> Jupiter comet family
- Ernest William Brown
- brown dwarf
- B star
- Bubble Nebula
- Budrosa family
- Bug Nebula
- bump Cepheid
- Geoffrey Ronald Burbidge
- Eleanor Margaret Burbidge
- burst (astronomy)
- Butcher–Oemler effect
- Butler matrix
- Butterfly Cluster
- butterfly diagram
- Butterfly Nebula
- BV photometry
- Bw star
- BY Draconis star
- Byurakan Astrophysical Observatory
C
edit- Caelum
- Calar Alto Observatory
- caldera
- calendar
- calendar year
- Caliban
- California Nebula
- Callippus
- Callisto
- Caloris Basin
- Caltech Submillimeter Observatory
- CSO
- Calypso (moon)
- Cambridge Optical Aperture Synthesis Telescope
- COAST
- Camelopardalis
- William Wallace Campbell
- Canada–France–Hawaii Telescope
- canale
- canali
- Martian canals
- Cancer
- Tropic of Cancer
- Canes Venatici
- Canis Major
- Canis Minor
- Annie Jump Cannon
- Canopus
- cantaloupe terrain
- Capella
- Cape Photographic Durchmusterung
- Cape photometry
- Cape RI photometry -> Kron–Cousins RI photometry
- Cape York meteorite
- Caph
- Tropic of Capricorn
- Capricornid meteors
- Capricornus
- captured rotation -> synchronous rotation
- Carafe Galaxy
- carbonaceous chondrite
- carbon burning
- carbon cycle -> carbon–nitrogen cycle
- carbon flash
- carbon–nitrogen cycle (CN cycle)
- carbon star
- Carina
- Carina Arm
- Carina Dwarf Galaxy
- Carina–Sagittarius Arm
- CARMA -> Combined Array for Research in Millimeter-wave Astronomy
- Carme
- Carnegie Observatories
- Carpo
- Richard Christopher Carrington
- Carrington heliographic coordinates
- Carrington rotation
- Carte du Ciel
- Cartesian coordinates
- Cartwheel Galaxy
- Cassegrain telescope
- Cassini
- Giovanni Domenico Cassini
- Jacques Cassini
- Cassini Division
- Cassini–Huygens
- Cassiopeia
- Cassiopeia A
- Castalia
- Castor
- cataclysmic binary
- cataclysmic variable
- catadioptric system
- Catalina Sky Survey
- catalogue equinox
- catena
- catoptric system
- Cat's Eye Nebula
- cavus
- CCD -> charge-coupled device
- CCD spectrometer
- C-class asteroid
- cD Galaxy
- CDM -> cold dark matter
- CDS -> Centre de Données astronomiques de Strasbourg
- celestial axis
- celestial coordinates
- celestial equator
- Celestial Intermediate Reference System
- celestial latitude
- celestial longitude
- celestial mechanics
- celestial meridian
- celestial pole
- celestial sphere
- Centaur group
- Centaurus
- Centaurus A
- Center for Astrophysics
- Central Bureau for Astronomical Telegrams
- central meridian
- central peak
- Centre de Données astronomiques de Strasbourg
- centre of gravity
- centre of inertia
- centre of mass
- centrifugal force
- centripetal force
- Cepheid instability strip
- Cepheid variable
- Cepheus
- Cerenkov counter
- Cerenkov radiation
- Ceres
- Cerro Pachón
- Cerro Paranal
- Cerro Tololo Inter-American Observatory
- Cetus
- CfA -> Harvard–Smithsonian Center for Astrophysics
- CGRO -> Compton Gamma Ray Observatory
- Chamaeleon
- Chandler period
- Chandler wobble
- Subrahmanyan Chandrasekhar
- Chandrasekhar limit
- Chandrasekhar-Schönberg limit
- Chandra X-ray Observatory
- Chandrayaan-1
- Chang'e
- chaos
- chaotic orbit
- chaotic terrain
- CHARA Array
- charge
- charge-coupled device
- Charon
- chasma
- chassignite
- chemical element
- chemosphere
- Chicxulub
- CHIPSat
- Chiron
- Ernst Florens Friedrich Chladni
- chondrite
- chondrule
- chopper
- chopping secondary
- William Henry Mahoney Christie
- chromatic aberration
- chromosphere
- chromospheric network
- Chryse Planitia
- CH star
- Circinus
- Circlet
- circular velocity
- circumpolar
- circumstellar maser
- circumstellar matter
- Cirrus Nebula -> Veil Nebula
- CIRS -> Celestial Intermediate Reference System
- cislunar
- civil time
- civil twilight
- civil year
- Alexis Claude Clairaut
- Alvan Clark
- classical Cepheid
- clast
- clathrate
- CLEAN
- Clementine
- James Clerk Maxwell
- C line
- clock drive -> drive
- clock star
- closed universe
- Clown Face Nebula -> Eskimo Nebula
- Cluster
- star cluster -> globular cluster
- star cluster -> open cluster
- cluster, star -> star cluster
- cluster of galaxies
- cluster variable -> RR Lyrae star
- CMB -> cosmic microwave background
- CME -> coronal mass ejection
- CM relation -> colour–magnitude relation
- CN band
- CN cycle -> carbon–nitrogen cycle
- CNO cycle -> carbon–nitrogen–oxygen cycle
- CN star
- Coalsack
- coaltitude
- COAST
- Coathanger
- COBE
- Cocoon Nebula
- cocoon star
- CoD -> Córdoba Durchmusterung
- coded mask
- coelostat
- coesite
- coherence
- coherence bandwidth
- colatitude
- cold camera
- cold dark matter
- collapsar
- colles
- collimation
- collimation error
- collimator
- Colombo Gap
- colorimetry -> colour index
- colour -> colour index
- colour excess
- colour index
- colour–luminosity relation -> colour–magnitude relation
- colour–magnitude relation
- colour temperature
- Columba
- column density
- colure
- cometary coma
- optical coma
- Coma Berenices
- Coma Cluster
- Coma Star Cluster
- Coma–Virgo Cluster -> Virgo Cluster
- Combined Array for Research in Millimeter-wave Astronomy
- combined magnitude
- comes
- comet
- cometary globule
- comet family
- comet-seeker
- commensurability
- Andrew Ainslie Common
- common envelope binary
- common proper motion
- compact galaxy
- compact object
- compact source
- comparator
- comparison spectrum
- composite-spectrum binary
- Compton effect
- Compton Gamma Ray Observatory
- Compton–Getting effect
- Compton scattering -> Compton effect
- Compton upscattering -> inverse Compton scattering
- Concordia family
- Cone Nebula
- confusion
- conic section
- conjunction
- constant of aberration -> annual aberration
- constellation
- constructive interference -> interference
- contact binary
- continuous creation
- continuous spectrum
- continuum
- stellar convection
- convective envelope
- convective equilibrium
- convective overshoot -> overshooting
- convective zone
- convergent point
- converging lens
- convolution
- Thomas Cooke
- cooled camera -> cold camera
- cooling flow
- coorbital
- Coordinated Universal Time
- coordinate systems -> celestial coordinates
- coordinate time
- Copernican system
- Nicolaus Copernicus
- Copernicus satellite
- Coprates
- Cor Caroli
- Cordelia
- Córdoba Durchmusterung
- planetary core
- stellar core
- core collapse
- 1
- 2
- Coriolis force
- corona
- 1
- 2
- 3
- Corona Australis
- Corona Borealis
- coronagraph
- coronal bright point
- coronal condensation
- coronal hole
- coronal lines
- coronal loop
- coronal mass ejection
- coronal plume
- coronal rain
- COROT
- co-rotation
- corpuscular radiation
- 1
- 2
- corrector plate
- correlation detection
- correlation function
- correlation receiver
- correlator
- Corvus
- COS-B
- cosmic abundance
- Cosmic Background Explorer
- cosmic background radiation -> cosmic microwave background
- CBR -> cosmic background radiation
- cosmic censorship
- cosmic dust
- cosmic microwave background
- cosmic rays
- cosmic-ray shower
- cosmic scale factor
- cosmic string
- cosmic texture
- cosmic year
- cosmochemistry -> astrochemistry
- cosmological constant
- cosmological distance scale
- cosmological principle
- cosmology
- cosmos
- Cosmos satellites
- COSPAR
- coudé focus
- Couder telescope
- counterglow -> gegenschein
- Philip Herbert Cowell
- c.p.m. -> common proper motion
- Crab Nebula
- Crab Pulsar
- Crater
- crater
- crater chain
- crater counting
- crêpe ring
- crepuscular rays
- crescent
- Cressida
- Crimean Astrophysical Observatory
- critical density
- Andrew Claude de la Cherois Crommelin
- cross-axis mounting
- crossing time
- cross-wire micrometer
- crown glass
- crust
- Crux
- cryostat
- cryovolcanism
- C star
- CTIO -> Cerro Tololo Inter-American Observatory
- Cubewano
- culmination
- curvature of field
- curvature of space -> curvature of spacetime
- curvature of spacetime
- curvature radiation
- curve of growth
- cusp
- cusp gap
- Cybele group
- cyclotron maser
- cyclotron radiation
- Cygnus
- Cygnus A
- Cygnus Loop
- Cygnus Rift
- Cygnus X-1
- Cynthian
- Cytherean
D
edit- Dactyl
- Dall–Kirkham telescope
- Damocles
- Damocloid
- André Danjon
- Danjon astrolabe
- Danjon scale
- dark adaptation
- dark energy
- dark galaxy
- dark matter
- dark nebula
- daughter isotope
- Davida
- David Dunlap Observatory
- Raymond Davis, Jr
- William Rutter Dawes
- Dawes limit
- Dawn
- day
- Daylight Saving Time -> Summer Time
- day number
- 1
- 2
- D-class asteroid
- DCT -> Discovery Channel Telescope
- DDO classification
- DDO photometry
- dec. -> declination
- deceleration parameter
- Comet de Chéseaux (C/1743 X1)
- declination
- declination axis
- deconvolution
- decoupling
- dedispersion
- Deep Impact
- deep-sky object
- Deep Space Network
- Deep Space 1
- defect of illumination
- deferent
- deflection of light
- degeneracy
- degenerate star
- degree of arc
- degrees of freedom
- Deimos
- delay line
- Delphinus
- δ -> declination
- delta -> declination
- Delta Aquarid meteors
- Delta Cepheid star -> classical Cepheid
- Delta Delphini star
- Delta Scuti star
- delta T
- ΔT
- Demon Star
- Deneb
- Deneb Kaitos
- Denebola
- William Frederick Denning
- density parameter
- density wave
- descending node
- Desdemona
- Willem de Sitter
- de Sitter universe
- Despina
- destructive interference -> interference
- detached binary
- deuterium
- Gérard Henri de Vaucouleurs
- dewar
- dew cap
- D galaxy
- diagonal
- diamond ring
- Diana Chasma
- dichotomy
- dichroic mirror
- Robert Henry Dicke
- Dicke radiometer
- Dicke switch
- dielectronic recombination
- differential rotation
- differentiation
- diffraction
- diffraction grating
- diffraction-limited
- diffraction pattern
- diffraction rings
- diffuse interstellar bands
- diffuse nebula
- diogenite
- Dione
- dioptric system
- Diphda -> Deneb Kaitos
- dipole
- 1
- 2
- 3
- dipole antenna
- Dirac cosmology
- directivity
- direct motion
- dirty snowball
- disconnection event
- Discovery Channel Telescope
- Discovery Program
- dish antennae
- disk galaxy
- disk population
- disparition brusque -> filament
- dispersion
- 1
- 2
- dispersion measure
- distance modulus
- distortion
- diurnal
- diurnal aberration
- diurnal inequality
- diurnal libration
- diurnal motion
- diurnal parallax
- diverging lens
- D layer
- D lines
- dMe star
- Dobsonian telescope
- Dog Star
- John Dollond
- domain wall
- dome
- Dominion Astrophysical Observatory
- Dominion Radio Astrophysical Observatory
- Comet Donati (C/1858 L1)
- Christian Johann Doppler
- Doppler broadening
- Doppler effect -> Doppler shift
- dopplergram
- Doppler shift
- Dorado
- dorsum
- Double Cluster
- Double Double
- double-lined binary
- double-mode variable
- double pulsar
- double quasar
- double star
- doublet
- 1
- 2
- DQ Herculis star
- Draco
- draconic month
- Draconid meteors -> Giacobinid meteors
- Drake equation
- Henry Draper
- Draper
- drawtube
- Johan Ludvig Emil Dreyer
- drifting sub-pulse
- drift scan
- drive
- D star
- Dubhe
- Dumbbell Nebula
- dust
- dust tail -> cometary tail
- duty cycle
- dwarf Cepheid
- dwarf galaxy
- dwarf nova
- dwarf planet
- dwarf spheroidal galaxy
- dwarf star
- dwarf variable
- Dwingeloo galaxy
- Dwingeloo Radio Observatory
- dynamical equinox
- dynamical friction
- dynamical parallax
- dynamical time
- dynamo
- Frank Watson Dyson
E
edit- Eagle Nebula
- early-type galaxy
- early-type star
- Earth
- Earth coorbital asteroid -> Apollo group -> Aten group
- Earth-crossing asteroid -> Amor group
- Earth-approaching asteroid
- earthlight -> earthshine
- eccentric anomaly
- eccentricity
- echelle grating
- echelle spectrograph
- E-class asteroid
- eclipse
- eclipse season
- eclipse year
- eclipsing binary
- ecliptic
- ecliptic coordinates
- ecliptic latitude
- ecliptic limits
- ecliptic longitude
- ecliptic pole
- E corona
- Arthur Stanley Eddington
- Eddington limit
- Edgeworth–Kuiper Belt -> Kuiper Belt
- E-ELT -> European Extremely Large Telescope
- effective aperture
- effective area
- effective focal length
- effective temperature
- Effelsberg Radio Observatory
- Egg Nebula
- Albert Einstein
- Einstein coefficient
- Einstein Cross
- Einstein–de Sitter universe
- Einstein Observatory
- Einstein ring
- Einstein shift -> gravitational redshift
- ejecta
- Elara
- E layer
- electromagnetic radiation
- electromagnetic spectrum
- electron
- electron degeneracy
- electron density
- electron scattering opacity
- electron temperature
- electronvolt
- chemical element
- optical element
- elementary particle
- abundance of elements
- orbital elements
- E line
- Ellerman bomb
- ellipse
- ellipsoid
- ellipsoidal variable
- elliptic aberration -> E-terms
- elliptical galaxy
- ellipticity -> oblateness
- Elnath -> Alnath
- elongation
- 1
- 2
- Eltanin -> Etamin
- Elysium Planitia
- emersion
- emission
- emission line
- emission nebula
- emission spectrum
- emissivity
- photographic emulsion
- Enceladus
- Comet 2P/Encke
- Johann Franz Encke
- Encke Division
- energy level
- English mounting
- Enif
- Ensisheim meteorite
- enstatite chondrite
- entrainment
- entropy
- envelope (astronomy)
- eon -> aeon
- Eos family
- epact
- Ep galaxy
- ephemeris
- Ephemeris Time
- epicycle
- Epimetheus
- epoch
- e-process
- Epsilon Aurigae
- equant
- equation (astronomy)
- equation of light
- equation of the centre
- equation of the equinoxes
- equation of the origins
- equation of time
- equator
- equatorial bulge
- equatorial coordinates
- equatorial horizontal parallax
- equatorial mounting
- equinoctial colure
- equinox
- equipotential surface
- equivalence principle
- equivalent focal length
- equivalent width
- Equuleus
- ERA -> Earth rotation angle
- Eratosthenes
- Erfle eyepiece
- ergosphere
- Eridanus
- Eris
- Eros
- eruptive binary
- eruptive prominence
- eruptive variable
- ESA -> European Space Agency
- escape velocity
- Eskimo Nebula
- ESO -> European Southern Observatory
- ET -> Ephemeris Time
- Eta Aquarid meteors
- Eta Carinae
- Eta Carinae Nebula
- etalon
- Etamin
- E-terms
- ether
- eucrite
- Eudoxus of Cnidus
- Leonhard Euler
- Eunomia family
- Europa
- European Extremely Large Telescope
- European Southern Observatory
- European Space Agency
- European VLBI Network
- EUV -> extreme ultraviolet
- EUVE -> Extreme Ultraviolet Explorer
- eV -> electronvolt
- evection
- evening star
- event horizon
- Evershed effect
- EVN -> European VLBI Network
- evolved star
- excitation
- excitation temperature
- exit cone
- exit pupil
- EX Lupi star
- exobiology -> astrobiology
- ExoMars
- exoplanet -> extrasolar planet
- EXor -> EX Lupi star
- Exosat
- exosphere
- expanding universe
- Explorer
- exposure age
- extended source
- 1
- 2
- atmospheric extinction
- interstellar extinction
- extragalactic nebula -> galaxy
- extrasolar planet
- extreme Population I star
- extreme ultraviolet
- Extreme Ultraviolet Explorer
- extrinsic variable
- eye lens
- eyepiece
- eye relief
F
edit- Faber–Jackson relation
- David Fabricius
- Johann Fabricius
- Johannes Fabricius
- Fabry lens
- Fabry–Perot interferometer
- facula
- 1
- 2
- fall
- falling star -> meteor
- False Cross
- Fanaroff–Riley class
- fan beam
- Faraday effect
- far infrared
- farrum
- far ultraviolet
- Far Ultraviolet Spectroscopic Explorer
- Fast Auroral Snapshot Explorer
- fast nova
- Faulkes Telescopes
- fault
- F band
- F-class asteroid
- F corona
- feed
- fermion
- fibrille
- field curvature -> curvature of field
- field equations
- field flattener
- field lens
- field of view
- field star
- field stop
- 53 Persei star
- figure
- filament
- 1
- 2
- filamentary nebula
- filar micrometer
- filigree
- filled aperture
- filled-centre supernova remnant -> plerion
- filter
- 1
- 2
- filtergram
- find
- finder
- fine structure
- fireball
- first contact
- first point of Aries
- first point of Libra
- first quarter
- Fish Mouth
- fission
- fission track
- Fitzgerald contraction -> Lorentz–Fitzgerald contraction
- fixed stars
- FK
- FK Comae Berenices star
- John Flamsteed
- Flamsteed numbers
- solar flare
- flare star
- flash spectrum
- flash star
- flat
- polar flattening
- F layer
- Williamina Paton Fleming
- flexus
- flickering
- flint glass
- flocculi
- 1 -> mottles
- 2 -> plages
- Flora group
- fluctus
- flumen
- fluorescence
- fluorite
- flux
- flux collector
- flux density
- 1
- 2
- flux tube
- flux unit
- f/number
- focal distance
- focal length
- focal plane
- focal point
- focal ratio
- focal reducer
- focal surface
- optical focus
- orbital focus
- Fokker–Planck equation
- folded dipole
- following
- Fomalhaut
- footpoint -> coronal loop
- forbidden line
- Forbush effect
- fork mounting
- Fornax
- Fornax A
- Fornax Dwarf Galaxy
- 47 Tucanae
- forward scattering
- fossa
- Foucault test
- four-colour photometry -> Strömgren photometry
- Fourier analysis
- Fourier transform
- Fourier transform spectrometer
- fourth contact
- William Alfred Fowler
- Fp star
- fractional method
- frame dragging
- frame of reference
- Franklin-Adams charts
- Joseph von Fraunhofer
- Fraunhofer lines
- Fred Lawrence Whipple Observatory
- free–bound transition
- free–free transition
- frequency
- frequency analysis -> Fourier analysis
- Friedmann universe
- fringe -> interference pattern
- fringe pattern
- f-spot
- F star
- FTS -> Fourier transform spectroscopy
- full Moon
- full-wave dipole
- full width at half maximum
- fundamental catalogue
- fundamental mode
- fundamental plane
- fundamental star
- fuor -> FU Orionis star
- FUSE -> Far Ultraviolet Spectroscopic Explorer
- fusion
- fusion crust
- future light cone -> light cone
- FWHM -> full width at half maximum
G
edit- g -> acceleration of free fall
- G -> gravitational constant
- Gacrux -> Gamma Crucis
- Gaia
- gain
- galactic anticentre
- galactic bulge
- galactic centre
- galactic cluster
- galactic coordinates
- galactic disk
- galactic equator
- galactic halo
- galactic latitude
- galactic longitude
- galactic magnetic field
- galactic nucleus
- galactic plane
- galactic pole
- galactic rotation
- galactic window
- galactic year -> cosmic year
- Galatea
- Galaxy
- galaxy
- galaxy cannibalism
- galaxy cluster
- galaxy encounter
- galaxy evolution
- Galaxy Evolution Explorer
- galaxy formation
- galaxy merger
- GALEX -> Galaxy Evolution Explorer
- Galilean satellites
- Galilean telescope
- Galileo
- Galileo Galilei
- Galileo National Telescope
- Galileo Regio
- Johann Gottfried Galle
- Galle Ring
- Gamma Cassiopeiae star
- Gamma Crucis
- Gamma Doradus star
- gamma-ray astronomy
- gamma-ray background
- gamma-ray burst
- Gamma-ray Large Area Space Telescope
- gamma rays
- gamma-ray telescope
- George Gamow
- Ganymede
- Sergei Illarionovich Gaposchkin -> Cecilia Payne-Gaposchkin
- Garnet Star
- gas giant -> giant planet
- Gaspra
- gas scintillation proportional counter
- gas tail -> cometary tail
- Carl Friedrich Gauss
- Gaussian gravitational constant
- G band
- G-class asteroid
- GCRS -> Geocentric Celestial Reference System
- GCVS -> General Catalogue of Variable Stars
- gegenschein
- Geminga
- Gemini
- Geminid meteors
- Gemini Observatory
- Gemma -> Alphekka
- General Catalogue of Variable Stars
- general precession
- general theory of relativity
- Genesis
- Geneva photometry
- geo-
- geocentric
- Geocentric Celestial Reference System
- geocentric coordinates
- Geocentric Coordinate Time
- geocentric equatorial parallax
- geocentric parallax
- geocorona
- geodesic
- geodesy
- Geographos
- geoid
- geomagnetic storm
- geomagnetism
- geometrical albedo
- geometrical libration -> optical libration
- georgiaite
- geostationary orbit
- geosynchronous orbit
- geotail -> magnetotail
- germanium detector
- German mounting
- GHA
- ghost crater
- Ghost of Jupiter
- Riccardo Giacconi
- Giacobinid meteors
- Comet 21P/Giacobini–Zinner
- giant branch
- Giant Magellan Telescope
- Giant Metrewave Radio Telescope
- giant molecular cloud
- giant planet
- giant star
- gibbous
- Gienah
- David Gill
- Ginga
- Giotto
- GLAST -> Gamma-ray Large Area Space Telescope
- Glauke
- glitch
- Global Oscillation Network Group
- globular cluster
- globule
- GMAT -> Greenwich Mean Astronomical Time
- GMC -> giant molecular cloud
- GMST -> Greenwich Mean Sidereal Time
- GMT -> Greenwich Mean Time
- GMT -> Giant Magellan Telescope
- gnomon
- Goddard Space Flight Center
- Gödel universe
- Thomas Gold
- Goldstone
- GONG -> Global Oscillation Network Group
- John Goodricke
- GoTo telescope
- Benjamin Apthorp Gould
- Gould's Belt
- graben
- interplanetary grains
- interstellar grains
- Granat
- grand unified theory
- Gran Telescopio Canarias
- granulation
- graticule -> reticle
- grating -> diffraction grating
- grating spectrometer
- gravitation
- gravitational acceleration
- gravitational collapse
- gravitational constant
- gravitational deflection
- gravitational energy
- gravitational field
- gravitational force
- gravitational instability
- gravitational lens
- gravitational mass
- gravitational radiation
- gravitational wave
- graviton
- gravity assist
- gravity gradient
- Gravity Probe B
- grazing-incidence telescope
- grazing occultation
- GRB -> gamma-ray burst
- Great Attractor
- Great Bear -> Ursa Major
- great circle
- Great Dark Spot
- greatest brilliancy
- greatest elongation
- Great Observatories
- Great Red Spot
- Great Rift
- Great September Comet (C/1882 R1)
- Great Wall
- Green Bank
- Green Bank Telescope
- green flash
- greenhouse effect
- Greenwich hour angle
- Greenwich Mean Astronomical Time
- Greenwich Mean Sidereal Time
- Greenwich Mean Time
- Greenwich meridian
- Greenwich Observatory
- Greenwich sidereal date
- Greenwich Sidereal Time
- Gregorian calendar
- Gregorian telescope
- James Gregory
- Comet 26P/Grigg–Skjellerup
- grism
- grooved terrain
- Grotrian diagram
- ground state
- GRS -> Great Red Spot
- Howard Grubb
- Grus
- GST -> Greenwich Sidereal Time
- G star
- GTC -> Gran Telescopio Canarias
- Guardians
- guest star
- guider
- guide star
- guide telescope
- Gum Nebula
- GUT -> grand unified theory
- GW Virginis star -> ZZ Ceti star
- gyrofrequency
- gyrosynchrotron radiation
H
edit- HA -> hour angle
- Hadar
- Hadley circulation
- Hadley Rille
- hadron
- hadron era
- HAEBE -> Herbig Ae/Be star
- Haedi -> Kids
- Haig mount -> Scotch mount
- Hakucho
- halation
- HALCA
- George Ellery Hale
- Comet Hale–Bopp (C/1995 01)
- Hale Observatories
- Hale's law -> bipolar group
- Hale telescope
- half-life
- half-wave dipole
- half-width -> full width at half maximum
- Asaph Hall
- Edmond Halley
- Halley-family comet
- Halley's Comet
- atmospheric halo
- galactic halo
- halo CME
- halo orbit
- halo population
- Hα
- Hamal
- H and K lines
- Hanle effect
- hard X-rays
- Haro galaxy
- Hartebeesthoek Radio Astronomy Observatory
- HartRAO -> Hartebeesthoek Radio Astronomy Observatory
- Hartmann test
- Haruka -> HALCA
- Harvard classification
- Harvard College Observatory
- Harvard Revised Photometry
- Harvard–Smithsonian Center for Astrophysics
- harvest Moon
- Hat Creek Radio Observatory
- Hathor
- Haute-Provence Observatory
- Stephen William Hawking
- Hawking radiation
- Hayabusa
- Hayashi track
- Haystack Observatory
- HCG -> Hickson compact group
- HD Catalogue -> Henry Draper Catalogue
- cometary head
- head–tail galaxy
- HEAO -> High Energy Astrophysical Observatory
- heat death of the Universe
- Heaviside layer -> E layer
- heavy element
- heavy-metal star
- Hebe
- Hektor
- Helene
- heli- -> Sun
- helio- -> Sun
- heliacal rising and setting
- heliocentric
- 1
- 2
- heliocentric coordinates
- heliocentric latitude
- heliocentric longitude
- heliocentric parallax -> annular parallax
- heliographic coordinates
- heliometer
- heliopause
- helioseismology
- heliosheath
- heliosphere
- Helios probes
- heliostat
- helium burning
- helium flash
- helium shell flash
- helium star
- Helix Nebula
- Hellas Planitia
- helmet streamer -> streamer
- Helmholtz–Kelvin contraction
- hemispherical albedo
- Henry Draper Catalogue
- Henyey track
- Hephaistos
- Heraclides of Pontus
- Herbig Ae/Be star
- Herbig–Haro object
- Hercules
- Hercules Cluster
- Hercules X-1
- Herculina
- Hermes
- Caroline Lucretia Herschel
- Karoline Lucretia Herschel -> Caroline Lucretia Herschel
- John Frederick William Herschel
- Frederick William Herschel -> William Herschel
- Friedrich Wilhelm Herschel -> William Herschel
- William Herschel
- Herschelian telescope
- Comet 35P/Herschel–Rigollet
- Herschel Space Observatory
- Hertha family -> Nysa family
- hertz
- Ejnar Hertzsprung
- Hertzsprung gap
- Hertzsprung–Russell diagram
- Victor Francis Hess
- HESSI -> Ramaty High-energy Solar Spectroscopic Imager
- HETE-2 -> High Energy Transient Explorer-2
- Johannes Hevelius
- Antony Hewish
- hexahedrite
- HH object -> Herbig–Haro object
- Hickson compact group
- Hidalgo
- hierarchical cosmology
- High Energy Astrophysical Observatory
- high-energy astrophysics
- High-Energy Transient Explorer-2
- lunar highlands
- high-speed photometry
- high-velocity cloud
- high-velocity star
- Hilda group
- George William Hill
- Himalia
- Hind's Crimson Star
- Hind's Variable Nebula
- Hinode
- Hinotori
- Hipparchus of Nicaea
- Hipparcos
- Hirayama family
- Hiten
- H line -> H and K lines
- H magnitude
- Hoba West meteorite
- Hobby–Eberly Telescope
- Hohmann orbit
- Holmberg radius
- homogeneity
- homology
- Homunculus Nebula
- H I region
- Hooker Telescope
- horizon
- horizontal branch
- horizontal coordinates
- horizontal parallax
- horizontal refraction
- horn antenna
- Horologium
- Jeremiah Horrocks
- Jeremiah Horrox -> Jeremiah Horrocks
- Horsehead Nebula
- horseshoe mounting
- Horseshoe Nebula
- horseshoe orbit
- horst
- hot Big Bang
- hot dark matter
- hot Jupiter
- hot spot
- 1
- 2
- hour angle
- hour circle
- Hourglass Nebula
- howardite
- Fred Hoyle
- HPBW -> half-power beamwidth
- half-power beamwidth -> beamwidth
- HR diagram -> Hertzsprung–Russell diagram
- HR number
- HSO -> Herschel Space Observatory
- HST -> Hubble Space Telescope
- H20 maser
- H II region
- Edwin Powell Hubble
- Hubble classification
- Hubble constant
- Hubble diagram
- Hubble flow
- Hubble law
- Hubble parameter -> Hubble constant
- Hubble radius
- Hubble–Sandage variable
- Hubble Space Telescope
- Hubble's Variable Nebula
- Hubble time
- William Huggins
- Hendrik ('Henk') Christoffel van de Hulst
- Milton Lasell Humason
- hummocky terrain
- Humphreys series
- Hungaria group
- hunter's Moon
- Huygenian eyepiece
- Christiaan Huygens
- Huygens Gap
- Huygens probe
- Hyades
- Comet Hyakutake (C/1996 B2)
- Hydra
- hydrocarbon
- hydrogen
- hydrogen burning
- hydrogen emission region
- hydrogen ion
- hydrogen line -> 21-centimetre line
- hydrogen spectrum
- hydrostatic equilibrium
- hydroxyl
- Hydrus
- Hygiea
- hyperbola
- hyperbolic comet
- hyperbolic orbit
- hyperbolic velocity
- hyperboloid
- hyperfine structure
- hypergiant star
- Hyperion
- hypernova
- hyperon
- hypersensitization
- hypersthene achondrite -> diogenite
- hypervelocity impact
- Hz -> hertz
- HZ43
I
edit- Iapetus
- IAU -> International Astronomical Union
- IC -> Index Catalogue
- Icarus
- ICE -> International Cometary Explorer
- ICRF -> International Celestial Reference Frame
- ICRS -> International Celestial Reference System
- Ida
- IGM -> intergalactic medium
- igneous
- IGY -> International Geophysical Year
- Comet Ikeya–Seki (C/1965 S1)
- Comet Ikeya–Zhang (153P/)
- illuminance
- IMAGE -> Imager for Magnetopause-to-Aurora Global Exploration
- image intensifier -> image tube
- Image Photon Counting System
- Imager for Magnetopause-to-Aurora Global Exploration
- image tube
- imaging photometer -> area photometer
- I magnitude
- Imbrium Basin
- immersion
- impact crater
- impactite
- impersonal astrolabe -> Danjon astrolabe
- inclination
- 1
- 2
- Index Catalogue
- indochinite
- Indus
- inequality
- inert gas -> noble gas
- inertial coordinate system
- inertial mass
- inertial reference frame
- infall velocity
- inferior conjunction
- inferior planet
- inflationary universe
- Infrared Astronomical Satellite
- infrared astronomy
- infrared cirrus
- infrared excess
- infrared photometry
- infrared radiation
- infrared source
- Infrared Space Observatory
- infrared telescope
- infrared window
- initial mass function
- Robert Thorburn Ayton Innes
- Innisfree meteorite
- insolation
- instability strip
- Institut de Radio Astronomie Millimétrique
- INT -> Isaac Newton Telescope
- INTEGRAL -> International Gamma-Ray Astrophysics Laboratory
- integrated magnitude
- integration time
- intensity
- intensity interferometer
- interacting binary
- interacting galaxy
- Interamnia
- interference
- 1
- 2
- interference filter
- interference pattern
- interferometer
- intergalactic absorption
- intergalactic magnetic field
- intergalactic medium
- intermediate-band photometry
- intermediate-population star
- intermediate-type star
- International Astronomical Union
- International Atomic Time
- International Celestial Reference Frame
- International Celestial Reference System
- International Cometary Explorer
- International Date Line
- International Gamma-Ray Astrophysics Laboratory
- International Geophysical Year
- International Sun–Earth Explorer
- International Sunspot Number
- International Ultraviolet Explorer
- International Years of the Quiet Sun
- interplanetary matter
- interplanetary scintillation
- interpulse
- interstellar absorption
- interstellar maser
- interstellar matter
- interstellar molecule
- interstellar reddening -> interstellar absorption
- interstellar scintillation
- interstellar wind
- intrinsic colour index
- intrinsic variable
- invariable plane
- inverse Compton effect
- inverse Compton scattering -> inverse Compton effect
- inverse P Cygni profile -> P Cygni profile
- inverse-square law
- inversion layer -> atmospheric transparency
- Io (moon)
- iodine cell
- ion
- ionization
- ionization equilibrium
- ionization front
- ionization potential
- ionization temperature
- ionopause
- ionosphere
- ionospheric scintillation
- ion tail -> cometary tail
- Iota Aquarid meteors
- IPCS -> Image Photon Counting System
- IQSY -> International Years of the Quiet Sun
- IR -> infrared
- IRAM -> Institut de Radio Astronomie Millimétrique
- IRAS -> Infrared Astronomical Satellite
- Comet IRAS–Araki–Alcock (C/1983 H1)
- Iris (asteroid)
- iron meteorite
- iron peak
- irradiance
- irradiation
- 1
- 2
- irregular galaxy
- irregular variable
- IRTF -> NASA Infrared Telescope Facility
- Isaac Newton Group
- Isaac Newton Telescope
- ISEE -> International Sun–Earth Explorer
- Ishtar Terra
- ISM -> interstellar matter -> interstellar medium
- ISO (observatory) -> Infrared Space Observatory
- isochron
- isochrone
- isophotal wavelength
- isophote
- isotherm
- isothermal process
- isothermal region
- isotope
- isotropy
- IUE -> International Ultraviolet Explorer
- Izar
J
edit- James Clerk Maxwell Telescope
- James Webb Space Telescope
- jansky
- Karl Guthe Jansky
- (Pierre) Jules César Janssen
- Janus (moon)
- JCMT -> James Clerk Maxwell Telescope
- JD -> Julian Date
- James Hopwood Jeans
- Jeans length
- Jeans mass
- jet (astronomical objects)
- Jet Propulsion Laboratory
- Jewel Box
- Jilin meteorite
- J magnitude
- Job's Coffin
- Jodrell Bank Observatory
- Johnson photometry
- Johnson Space Center
- Joint Astronomy Centre
- Harold Spencer Jones
- joule
- Jovian planet
- JPL -> Jet Propulsion Laboratory
- Julian calendar
- Julian Date
- Julian day number
- Julian epoch
- Juliet (moon)
- Juno (asteroid)
- Jupiter (planet)
- Jupiter–family comet
- JWST -> James Webb Space Telescope
K
edit- K -> kelvin scale
- Immanuel Kant
- Kappa Crucis Cluster -> Jewel Box cluster
- Kappa Cygnid meteors
- kappa mechanism
- Jacobus Cornelius Kapteyn
- Kapteyn Selected Areas
- Kapteyn's Star
- Kaus Australis
- K corona
- K-correction
- Keck Telescopes
- Keeler Gap
- Kellner eyepiece
- Lord (William Thomson) Kelvin
- Kelvin–Helmholtz contraction -> Helmholtz–Kelvin contraction
- kelvin scale
- Kennedy Space Center
- Kepler (satellite)
- Johannes Kepler
- Johann Kepler -> Johannes Kepler
- Keplerian telescope
- Kepler's equation
- Kepler's laws
- Kepler's Star
- Kerr black hole
- Keyhole Nebula
- Keystone
- Kids (asterism)
- kinematic parallax
- kinetic energy
- kinetic temperature
- Gustav Robert Kirchhoff
- Kirchhoff's laws
- Kirin meteorite -> Jilin meteorite
- Daniel Kirkwood
- Kirkwood gaps
- Kitt Peak National Observatory
- Kleinmann–Low Nebula
- KL Nebula -> Kleinmann–Low Nebula
- K line -> H and K lines
- K magnitude
- knife-edge test -> Foucault test
- Kochab
- Comet Kohoutek (C/1973 E1)
- König eyepiece -> Erfle eyepiece
- Koronis family
- KPNO -> Kitt Peak National Observatory
- Kracht group
- Kramers opacity
- KREEP
- Kreutz sungrazer
- Kron–Cousins RI photometry
- Kruskal diagram
- K star
- Kueyen
- Gerard Peter Kuiper
- Kuiper Airborne Observatory
- Kuiper Belt
L
edit- labes
- labyrinthus
- Nicolas Louis de Lacaille
- Lacerta
- Lacertid -> BL Lacertae object
- lacus
- Lagoon Nebula
- Joseph Louis de Lagrange(-Tournier)
- Lagrangian point
- l'Aigle meteorite shower
- Joseph Jérôme (Le Français) de Lalande
- Lalande 21185
- Lambda Boötis star
- Lambda Eridani star
- La Palma -> Roque de los Muchachos Observatory
- Pierre Simon de Laplace
- Laplacian plane
- Large Binocular Telescope
- Large Magellanic Cloud
- Large Millimeter Telescope
- large-scale structure
- Large Synoptic Survey Telescope
- Larissa
- Las Campanas Observatory
- laser
- Laser Interferometer Space Antenna
- La Silla Observatory
- William Lassell
- Lassell ring
- last contact
- last quarter
- La Superba
- late heavy bombardment
- late-type galaxy
- late-type star
- latitude
- latitude variation
- LBV -> luminous blue variable
- L dwarf
- leap second
- leap year
- least circle of confusion -> astigmatism -> spherical aberration
- Henrietta Swan Leavitt
- Leda (moon)
- Georges Édouard Lemaître
- Lemaître universe
- lens
- Lense–Thirring effect -> frame dragging
- gravitational lens
- lenticula
- lenticular galaxy
- Leo (constellation)
- Leo Minor (constellation)
- Leonid meteors
- lepton
- lepton era
- Lepus
- Leto family
- Urbain Jean Joseph Le Verrier <-> Urbain Jean Joseph Leverrier
- Le Verrier Ring
- Comet Lexell (D/1770 L1)
- LHA -> local hour angle
- Libra (constellation)
- first point of Libra
- libration
- libration point -> Lagrangian point
- Lick Observatory
- light
- speed of light
- light bucket -> flux collector
- light cone
- light-curve
- light pollution
- light pressure -> radiation pressure
- light time
- light year
- limb
- limb brightening
- limb darkening
- limiting magnitude
- 1
- 2
- Lincoln Near-Earth Asteroid Research
- Bertil Lindblad
- Lindblad resonance
- linea
- LINEAR
- line blanketing
- line broadening
- line of apsides
- line of inversion -> magnetic inversion line
- line of nodes
- line profile
- liner
- line ratio
- line receiver
- line spectrum
- linewidth
- line wing
- lingula
- LISA -> Laser Interferometer Space Antenna
- LISA Pathfinder
- Lissajous orbit
- lithium star
- lithosiderite -> stony-iron meteorite
- lithosphere
- Little Dipper
- Little Dumbbell
- Liverpool Telescope
- L magnitude
- LMC -> Large Magellanic Cloud
- LMT -> Large Millimeter Telescope
- lobate ridge
- lobate scarp
- lobe
- 1
- 2
- local arm
- local bubble
- Local Group
- local hour angle
- local mean time
- local sidereal time
- local standard of rest
- local supercluster
- local thermodynamic equilibrium
- local time
- Lockman hole
- (Joseph) Norman Lockyer
- lodranite
- LOFAR -> Low Frequency Array
- LONEOS -> Lowell Observatory Near-Earth Object Search
- long-baseline interferometry
- longitude
- longitude at the epoch
- longitude of perigee
- longitude of perihelion
- longitude of the ascending node
- long-period comet
- long-period variable
- lookback time
- loop prominence
- Lorentz–Fitzgerald contraction
- Lorentz transformation
- Lost City meteorite
- (Alfred Charles) Bernard Lovell
- Lovell Telescope
- Percival Lowell
- Lowell Observatory
- Lowell Observatory Near-Earth Object Search
- lower culmination
- Low Frequency Array
- low-luminosity star
- low-mass star
- low surface brightness galaxy
- low-velocity star
- LRO -> Lunar Reconnaissance Orbiter
- LSR -> local standard of rest
- LSST -> Large Synoptic Survey Telescope
- LST -> local sidereal time
- LTP -> lunar transient phenomenon
- luminosity
- luminosity class
- luminosity evolution -> galaxy evolution
- luminosity function
- luminosity–volume test
- luminous arc
- luminous blue variable
- Luna (Moon probes)
- lunar eclipse
- lunar inequality
- Lunar Module
- Lunar Orbiter
- lunar parallax
- Lunar Prospector
- Lunar Reconnaissance Orbiter
- lunar theory -> lunar inequality
- lunar transient phenomenon
- lunation
- Knut Emil Lundmark
- lunisolar precession
- lunitidal interval
- Lunokhod
- Lupus
- Lutz–Kelker bias
- Willem ('William') Jacob Luyten
- l.y. -> light year
- Lydia family
- Lyman-α forest
- Lyman-break Galaxy
- Lyman limit
- Lyman series
- Lynx (constellation)
- Bernard Ferdinand Lyot
- Lyot filter -> birefringent filter
- Lyra (constellation)
- Lyrid meteors
- Lysithea
M
edit- m -> apparent magnitude
- M -> Messier Catalogue
- M -> absolute magnitude
- MACHO
- Mach's principle
- macrospicules
- macroturbulence
- macula
- Maffei Galaxies
- Magdalena Ridge Observatory
- Magellan
- Magellanic Clouds
- Magellanic Stream
- Magellan Telescopes
- magma
- magnetar
- magnetic inversion line
- magnetic monopole
- magnetic star
- magnetic storm -> geomagnetic storm
- magnetic variable
- magnetobremsstrahlung
- magnetogram
- magnetohydrodynamics
- magnetopause
- magnetosheath
- magnetosphere
- magnetotail
- magnification
- magnitude
- magnitude of an eclipse
- main beam
- main-belt asteroid -> asteroid belt
- main lobe -> main beam
- main sequence
- major axis
- Maksutov telescope
- Malin-1
- Malmquist bias
- manganese–mercury star -> mercury–manganese star
- manganese star
- mantle
- many-body problem -> n-body problem
- mare (astronomy)
- Maria family
- Mariner
- Mariner Valley -> Valles Marineris
- Markab
- Markarian galaxy
- Mars (planet)
- Marsden group
- Mars Exploration Rover
- Mars Express
- Mars Global Surveyor
- Marshall Space Flight Center
- Mars Odyssey (2001 Mars Odyssey)
- Mars Pathfinder
- Mars probes
- Mars Reconnaissance Orbiter
- mascon
- maser
- maser amplifier
- maser source
- Nevil Maskelyne
- mass
- mass defect
- mass discrepancy
- mass function
- mass loss
- mass–luminosity relation
- mass–radius relation
- mass ratio
- mass-to-light ratio
- mass transfer
- John Cromwell Mather
- matter era
- Mauna Kea Observatories
- (Edward) Walter Maunder
- Maunder minimum
- maximum-entropy method
- James Clerk Maxwell
- Maxwell Gap
- Maxwell Montes
- Maxwell Telescope -> James Clerk Maxwell Telescope
- Mayall Telescope
- McDonald Observatory
- McIntosh scheme -> sunspot
- M-class asteroid
- McMath–Pierce Solar Telescope
- MDM Observatory
- mean anomaly
- mean daily motion
- mean density of matter
- mean equator
- mean equinox
- mean motion
- mean parallax -> statistical parallax
- mean place
- mean pole
- mean position -> mean place
- mean sidereal time
- mean solar day
- mean solar time
- mean sun
- mean time
- medium-band photometry
- megamaser
- megaregolith
- Megrez
- Melipal
- meniscus lens
- meniscus Schmidt telescope
- Menkalinan
- Menkar
- Mensa (constellation)
- mensa (planets)
- Donald Howard Menzel
- Merak
- Mercury
- mercury-manganese star
- Mercury Surface, Space Environment, Geochemistry, and Ranging
- celestial meridian
- terrestrial meridian
- meridian angle
- meridian astronomy
- meridian circle
- meridian passage -> meridian transit
- meridian telescope -> meridian circle -> transit circle -> transit instrument
- meridian transit
- MERLIN -> Multi-Element Radio-Linked Interferometer Network
- meson
- mesopause
- mesosiderite
- mesosphere
- MESSENGER -> Mercury Surface, Space Environment, Geochemistry, and Ranging
- Charles Joseph Messier
- Messier Catalogue
- Me star
- metagalaxy
- metal
- metallic hydrogen
- metal-poor star
- metal-rich star
- metastable state
- meteor
- Meteor Crater
- meteorite
- meteoroid
- meteor shower
- meteor storm
- meteor stream
- meteor swarm
- methanol maser
- Metis
- Metonic cycle
- Meudon Observatory
- Meyer group
- MHD -> magnetohydrodynamics
- Miaplacidus
- Mice (galaxies)
- Albert Abraham Michelson
- Michelson interferometer
- Michelson–Morley experiment
- Michelson stellar interferometer -> stellar interferometer
- microchannel plate detector
- microdensitometer
- microlensing
- micrometeorite
- micrometer (measuring instrument)
- micrometre
- micron
- micropore optics
- Microscopium (constellation)
- microturbulence
- Microvariability and Oscillations of Stars
- microvariable
- microwave background radiation
- microwaves
- Midcourse Space Experiment
- Mie scattering
- Milky Way
- millimetre-wave astronomy
- millimetre waves
- millisecond pulsar
- Mills cross
- Edward Arthur Milne
- Milne–Eddington approximation
- Mimas (moon)
- Mimosa -> Beta Crucis
- Hermann Minkowski
- Rudolph Leo Bernhard Minkowski
- minor axis
- minor planet -> asteroid
- Minor Planet Center
- Mintaka
- minute
- minute of arc <-> arcmin
- Mira
- Mirach
- Miranda (moon)
- Mira star
- Mirphak
- mirror
- mirror blank
- Mirzam
- missing mass
- Maria Mitchell
- Mittenzwey eyepiece
- mixing ratio
- Mizar
- MJD -> Modified Julian Date
- MK classification -> Morgan–Keenan classification
- MKK classification -> Morgan–Keenan classification
- M magnitude
- MMT Observatory
- mock Moon -> parselene
- mock Sun -> parhelion
- Modified Julian Date
- moldavite
- molecular cloud
- molecular hydrogen
- molecular line
- molecule
- Molonglo Radio Observatory
- moment of inertia
- MONET -> Monitoring Network of Telescopes
- Monitoring Network of Telescopes
- monocentric eyepiece
- Monoceros (constellation)
- monochromatic light
- monochromatic magnitude
- monochromator
- Monogem Ring
- monopole -> magnetic monopole
- mons (planets)
- month
- Monthly Notices of the Royal Astronomical Society
- Mont Mégantic Observatory -> Observatoire du Mont-Mégantic
- Moon
- Mopra Observatory
- Moreton wave
- William Wilson Morgan
- Morgan–Keenan classification
- Morgan's classification
- morning star
- MOST -> Microvariability and Oscillations of Stars
- mottles
- Mount Graham International Observatory
- mounting
- Mount Palomar Observatory -> Palomar Observatory
- Mount Stromlo and Siding Spring Observatories
- Mount Wilson classification -> sunspot
- Mount Wilson Observatory
- moustache -> Ellerman bomb
- moving cluster
- MRAO -> Mullard Radio Astronomy Observatory
- M region
- MRO -> Magdalena Ridge Observatory
- MSSSO -> Mount Stromlo and Siding Spring Observatories
- MS star
- 1
- 2
- M star
- MSX -> Midcourse Space Experiment
- Mu Cephei star
- Mullard Radio Astronomy Observatory
- Johann Müller -> Regiomontanus
- multi-beam receiver
- Multi-Element Radio-Linked Interferometer Network
- multiple star
- multiplet
- multi-ringed basin -> impact basin
- multiverse
- muon
- mural circle
- Musca (constellation)
N
edit- nadir
- Nagler eyepiece
- Naiad
- Nal detector
- naked eye
- naked singularity
- nakhlite
- Nançay Radio Astronomy Observatory
- nanometre
- Naos
- narrow-band photometry
- NASA -> National Aeronautics and Space Administration
- NASA Infrared Telescope Facility
- Nasir Eddin -> al-Tusi
- Nasser Eddin -> al-Tusi
- Nasmyth focus
- National Aeronautics and Space Administration
- National Astronomy and Ionosphere Center -> Arecibo Observatory
- National Optical Astronomy Observatory
- National Radio Astronomy Observatory
- National Solar Observatory
- National Space Science Data Center
- The Nautical Almanac
- nautical twilight
- n-body problem
- NEA -> near-Earth asteroid
- neap tide
- near-Earth asteroid
- Near-Earth Asteroid Tracking
- near infrared
- NEAR Shoemaker
- near ultraviolet
- NEAT -> Near-Earth Asteroid Tracking
- nebula
- nebula filter
- nebular line
- nebular variable
- nebulosity
- negative eyepiece
- negative lens -> diverging lens
- Neptune (planet)
- Nereid (moon)
- Neumann lines
- neutral hydrogen
- neutral hydrogen line -> 21-centimetre line
- neutral point
- neutrino
- neutrino astronomy
- neutron
- neutron degeneracy
- neutron star
- Simon Newcomb
- New General Catalogue
- New Horizons
- New Millennium Program
- new Moon
- New Style date
- New Technology Telescope
- newton
- Isaac Newton
- Newtonian–Cassegrain telescope
- Newtonian focus
- Newtonian telescope
- Newton's law of gravitation
- Newton's laws of motion
- N galaxy
- NGC -> New General Catalogue
- nickel–iron meteorite -> iron meteorite
- Nicol prism
- nightglow -> airglow
- night sky brightness
- night vision
- Nix Olympica -> Olympus Mons
- NLC -> noctilucent clouds
- nm -> nanometre
- N magnitude
- NOAO -> National Optical Astronomy Observatory
- Nobeyama Radio Observatory
- noble gas
- noctilucent clouds
- nocturnal
- nodal line
- node
- nodical month -> draconic month
- non-baryonic matter
- non-gravitational force
- non-radial pulsation
- non-thermal radiation
- Nordic Optical Telescope
- Norma (constellation)
- normal astrograph
- North America Nebula
- Northern Coalsack -> Great Rift
- Northern Cross -> Cygnus (constellation)
- northern lights -> aurora (astronomy)
- North Galactic Spur
- north polar distance
- North Polar Sequence
- North Star -> Polaris
- nova
- nova-like variable
- NPD -> north polar distance
- NRAO -> National Radio Astronomy Observatory
- NS -> New Style date
- NSO -> National Solar Observatory
- NSSDC -> National Space Science Data Center
- N star -> carbon star
- NTT -> New Technology Telescope
- Nubecula Major -> Magellanic Clouds
- Nubecula Minor -> Magellanic Clouds
- nuclear fusion
- nuclear reaction
- nuclear time-scale
- nucleon
- nucleosynthesis
- atomic nucleus
- cometary nucleus
- galactic nucleus
- null geodesic
- number evolution -> galaxy evolution
- Nunki
- nutation
- nutation in right ascension -> equation of the equinoxes
- Nysa family
O
edit- OAO -> Orbiting Astronomical Observatory
- OB association
- Oberon
- object glass
- objective
- objective grating
- objective prism
- oblateness
- oblate spheroid -> spheroid
- oblique rotator
- obliquity of the ecliptic
- Observatoire du mont Mégantic
- observatory
- occultation
- occulting bar
- occulting disk
- oceanus
- OC star
- octahedrite
- Octans (constellation)
- ocular -> eyepiece
- Oe star
- off-axis guider
- Of star
- o.g. -> object glass
- OH–IR source
- OH line
- OH maser
- OHP -> Haute-Provence Observatory
- Heinrich Wilhelm Matthäus Olbers
- Olbers' paradox
- Old Style date
- Oljato (asteroid)
- Olympus Mons
- O magnitude
- Omega Centauri
- Omega Nebula
- Onsala Space Observatory
- ON star
- Jan Hendrik Oort
- Oort Cloud
- Oort's constants
- Oosterhoff group
- Ootacamund Radio Astronomy Centre
- opacity
- open cluster
- open universe
- Ophelia (moon)
- Ophiuchid meteors
- Ophiuchus (constellation)
- Ernst Julius Öpik
- Oppenheimer–Volkoff limit
- Opportunity (Mars rover)
- opposition (astronomy)
- opposition effect
- optical axis
- optical depth
- optical double
- optical flat
- optical glass
- optical interferometer
- optical libration
- optical pathlength
- optical pulsar
- optical thickness -> optical depth
- optical wedge
- optics
- orbit
- orbital elements
- orbital velocity
- Orbiting Astronomical Observatory
- Orbiting Solar Observatory
- ordinary chondrite
- organic molecule
- Orgueil meteorite
- Orientale Basin
- Orion (constellation)
- Orion Arm
- Orion Association
- Orionid meteors
- Orion Molecular Clouds
- Orion Nebula
- Orion Spur
- Orion variable
- ORM -> Roque de los Muchachos Observatory
- orrery
- orthoscopic eyepiece
- OS -> Old Style date
- oscillating universe
- osculating elements
- osculating orbit
- OSO -> Orbiting Solar Observatory
- O star
- OT -> Teide Observatory
- outgassing
- 1
- 2
- overcontact binary
- oversampling
- overshooting
- overtone mode
- OVV quasar -> optically violently variable quasar -> blazar
- Owens Valley Radio Observatory
- Owl Nebula
- oxygen burning
- ozonosphere
P
edit- PA -> position angle
- PAH -> polycyclic aromatic hydrocarbon
- pair annihilation
- pair production
- palimpsest
- Pallas (asteroid)
- pallasite
- Palomar Observatory
- Palomar Observatory Sky Survey
- palus
- Pan (moon)
- Pandora (moon)
- Pan-STARRS
- parabola
- parabolic antenna
- parabolic comet
- parabolic orbit
- parabolic velocity
- paraboloid
- parallactic angle
- parallactic ellipse
- parallactic inequality
- parallactic motion
- parallax
- parametric amplifier
- Paranal Observatory
- paraxial
- parent isotope
- parfocal
- parhelion
- Paris Observatory
- Parkes Observatory
- parsec
- parselene
- William Parsons -> Third Earl of Rosse
- partial eclipse
- particle -> elementary particle
- pascal (unit)
- Paschen–Back effect
- Paschen series
- Pasiphae (moon)
- passband
- past light cone -> light cone
- patera
- pathlength -> optical pathlength
- Paul Wild Observatory
- Pavo (constellation)
- Cecilia Helena Payne-Gaposchkin
- pc -> parsec
- P-class asteroid
- P Cygni line profile
- P Cygni star -> S Doradus star
- Peacock (star)
- peculiar galaxy
- peculiar motion
- peculiar star
- peculiar velocity
- pedestal crater
- Peekskill meteorite
- Pegasus (constellation)
- Pele
- Pelican Nebula
- Penrose process
- penumbra
- 1
- 2
- penumbral eclipse
- Arno Allan Penzias
- perfect cosmological principle
- peri-
- periapsis
- periastron
- periastron effect
- pericentre
- perigee
- perihelion
- time of perihelion passage
- orbital period
- period–age relation
- period–colour relation
- period–density relation
- periodic comet
- periodic orbit
- periodic perturbation
- period–luminosity–colour relation
- period–luminosity relation
- period–mass relation
- period–radius relation
- period–spectrum relation
- Perseid meteors
- Perseus (constellation)
- Perseus A
- Perseus Arm
- Perseus Cluster
- personal equation
- perturbation
- Petzval surface
- Pfund series
- PHA -> Potentially Hazardous Asteroid
- Phad
- Phaethon (asteroid)
- phase
- 1
- 2
- phase angle
- phased array
- phase defect
- phase diagram
- phase difference
- phase rotator
- phase-switching interferometer
- phase transition -> inflationary universe
- Phecda -> Phad
- Pherkad
- Phillips bands
- Phobos (moon)
- Phobos probes
- Phocaea group
- Phoebe (moon)
- Phoenicid meteors
- Phoenix (constellation)
- Phoenix (Mars lander)
- Pholus (asteroid)
- photino
- photocathode
- photocell -> photoelectric cell
- photocentre
- 1
- 2
- photoconductive cell
- photodissociation
- photodissociation region
- photoelectric cell
- photoelectric magnitude
- photoelectric photometer
- photographic amplification
- photographic emulsion
- photographic magnitude
- photographic zenith tube
- photoheliograph
- photoionization
- photometer
- photometric binary
- photometric parallax
- photometric standard -> standard star
- photometry
- photomultiplier
- photon
- photon sphere
- photopolarimeter -> polarimeter
- photosphere
- photovisual magnitude
- photovoltaic detector
- physical albedo -> geometrical albedo
- physical double
- physical libration
- Giuseppe Piazzi
- Pic du Midi Observatory
- Edward Charles Pickering
- William Henry Pickering
- Pickering Series
- Pico Veleta
- Pictor (constellation)
- pincushion distortion
- Pinwheel Galaxy
- pion
- Pioneer
- Pioneer Venus
- Pipe Nebula
- Pisces (constellation)
- Piscid meteors
- Piscis Austrinid meteors
- Piscis Austrinus (constellation)
- pitch angle
- pixel
- plage
- Planck (spacecraft)
- Planck constant
- Planck era
- Planck's law
- planemo
- planet
- planetarium
- planetary aberration
- planetary aspect -> aspect
- planetary migration
- planetary nebula
- planetary precession
- planetesimal
- planetoid -> asteroid -> Giuseppe Piazzi
- planetology
- planisphere
- planitia
- planoconcave lens
- planoconvex lens
- planum
- John Stanley Plaskett
- Plaskett's Star
- plasma
- plasmapause
- plasmasphere
- plasma tail -> cometary tail
- Plateau de Bure
- plate centre
- plate constants
- plate-measuring machine
- plate scale
- plate tectonics
- Platonic year
- PLC relation -> period–luminosity–colour relation
- Pleiades
- plerion
- Plössl eyepiece
- Plough (asterism)
- PL relation -> period–luminosity relation
- plume
- 1
- 2
- Plutino
- Pluto
- P magnitude
- Pockels cell
- Norman Robert Pogson
- Pogson ratio
- Pogson scale
- Pogson step method
- (Jules) Henri Poincaré
- Pointers
- point source
- point-spread function
- polar -> AM Herculis star -> DQ Herculis star
- polar axis
- polar cap
- polar diagram
- polar distance
- polar flattening
- polarimeter
- polarimetry -> polarization
- Polaris
- polarization
- polar motion
- polar orbit
- polar plume -> coronal plume
- polar ring galaxy
- polar sequence
- polar wandering
- pole
- pole star
- Pollux
- polycyclic aromatic hydrocarbon
- John Pond
- Jean Louis Pons
- stellar population
- Population I
- Population II
- Population III
- pore
- Porrima
- Porro prism
- Portia (moon)
- positional astronomy -> astrometry -> meridian astronomy
- position angle
- position-angle effect
- position circle
- position micrometer -> filar micrometer
- positive lens -> converging lens
- POSS -> Palomar Observatory Sky Survey
- post-nova
- potassium–argon method
- potential hazardous asteroid
- power spectrum
- Poynting–Robertson effect
- PPM Star Catalogue
- p-process
- Praesepe
- preceding
- precession
- precession constant
- precession of the equinoxes
- precursor pulse
- pre-nova
- pressure broadening
- Príbram meteorite
- primary cosmic ray
- primary minimum
- primary mirror
- prime focus
- prime meridian
- prime vertical
- primordial fireball
- primordial galaxy
- Principia
- principle of equivalence -> equivalence principle
- prism
- prismatic astrolabe
- probable error
- Procyon
- prograde motion -> direct motion
- prolate spheroid -> spheroid
- Prometheus (moon)
- prominence
- prominence spectroscope
- promontorium
- proper motion
- proper time
- proplyd
- proportional counter
- Prospero (moon)
- Proteus (moon)
- protogalaxy
- proton
- proton–proton reaction
- protoplanet
- protoplanetary nebula
- 1
- 2
- protostar
- protosun
- Proxima Centauri
- p-spot
- Ptolemaic system
- Ptolemy <-> Claudius Ptolemaeus
- Publications of the Astronomical Society of the Pacific
- Puck (moon)
- Pulcherrima -> Izar
- pulsar
- pulsating variable
- pulsation mode
- pulse broadening
- pulse profile
- pulse width
- Pup (Sirius B)
- pupil
- Puppid–Velid meteors
- Puppis (constellation)
- Purkinje effect
- PV Telescopii star
- Pyxis
- PZT -> photographic zenith tube
Q
edit- Q-class asteroid
- Q magnitude
- QSO -> quasi-stellar object
- QSS -> quasi-stellar radio source
- quadrant
- Quadrantid meteors
- quadrature
- quadrupole
- quantum
- quantum cosmology
- quantum efficiency
- quantum gravitation
- quantum theory
- Quaoar
- quark
- quark star
- quasar
- quasi-stellar object
- quasi-stellar radio source
- quiescent prominence
- quiet sun
- quintessence -> dark energy
R
edit- RA -> right ascension
- radar astronomy
- radar meteor
- radial pulsation
- radial velocity
- radial-velocity spectrometer
- radian
- radiant
- radiation
- radiation belt
- radiation era
- radiation laws -> Planck's law -> Stefan–Boltzmann law -> Wien's displacement law
- radiation pressure
- radiation temperature
- radiative equilibrium
- radiative recombination -> free–bound transition
- radiative transfer
- radiative zone
- radioactive age dating
- radio astrometry
- RadioAstron
- radio astronomy
- radio galaxy
- radiogenic
- radioheliograph
- radio interferometer
- radio jet -> jet (astronomy)
- radio meteor
- radiometer
- radiometric dating -> radioactive age dating
- radionuclide
- radio source
- radio star
- radio telescope
- radio waves
- radio window
- radius–luminosity relation
- radius of curvature
- radius vector
- Raman effect
- Ramaty High-Energy Solar Spectroscopic Imager
- rampart crater
- Ramsden disk
- Ramsden eyepiece
- Ranger (Moon probes)
- RAS -> Royal Astronomical Society
- Rasalgethi
- Rasalhague
- Ra-Shalom (asteroid)
- R association
- raster
- raster scan
- RAS thread
- RATAN-600
- Rayleigh criterion
- Rayleigh–Jeans formula
- Rayleigh limit -> Rayleigh criterion
- Rayleigh number
- Rayleigh scattering
- crater rays
- R Canis Majoris star
- R-class asteroid
- R Coronae Borealis star
- Grote Reber
- receiver
- 1
- 2
- reciprocity failure
- recombination
- recombination epoch
- recombination line
- rectangular coordinates
- recurrent nova
- recycled pulsar
- reddening
- red dwarf
- red giant
- Red Planet -> Mars (planet)
- redshift
- redshift–distance relation
- redshift–magnitude relation
- Red Spot -> Great Red Spot
- reduced proper motion
- red variable
- reference frame -> frame of reference
- reference star
- reflectance spectrum
- reflecting telescope
- reflection effect
- reflection grating
- reflection nebula
- reflection variable
- reflector -> reflecting telescope
- refracting telescope
- atmospheric refraction
- refractive index
- refractor -> refracting telescope
- refractory
- regio
- Regiomontanus
- regmaglypt
- regolith
- regression of nodes
- Regulus
- relative orbit
- relative sunspot number
- relativistic beaming
- relativistic velocity
- relativity
- relaxation time
- remote sensing
- réseau
- residuals
- resolution -> resolving power
- resolving power
- resonance
- resonance line
- resonant scattering
- rest mass
- restricted three-body problem
- retardation
- retardation plate -> wave plate
- reticle
- Reticulum (constellation)
- reticulum (planets)
- retrograde motion
- reversing layer
- revolution
- RFT -> richest-field telescope
- RGO -> Royal Greenwich Observatory
- RGU photometry
- Rhea (moon)
- RHESSI -> Ramaty High-Energy Solar Spectroscopic Imager
- Rho Cassiopeiae star
- Rho Ophiuchi Nebula
- Richardson–Lucy algorithm
- richest-field telescope
- Rigel
- right ascension
- Rigil Kentaurus -> Alpha Centauri
- rille (Moon)
- rima
- planetary ring
- ring arcs
- ring galaxy
- Ring Nebula
- rise time
- rising
- George Willis Ritchey
- Ritchey–Chrétien telescope
- R magnitude
- Robertson–Walker metric
- Roche limit
- Roche lobe
- ROE -> Royal Observatory, Edinburgh
- Ole Christensen Römer
- Olaus Christensen Römer -> Ole Christensen Römer
- Ronchi test
- Rood–Sastry type
- roof prism
- Roque de los Muchachos Observatory
- Rosalind (moon)
- Rosat
- Rosetta
- Rosette Nebula
- Frank Elmore Ross
- Third Earl of Rosse <-> William Parsons
- Rosseland mean opacity
- Bruno Benedetto Rossi
- Rossiter effect
- Rossi X-ray Timing Explorer
- rotating variable
- rotation
- rotation curve
- rotation effect -> Rossiter effect
- rotation measure
- Royal Astronomical Society
- Royal Greenwich Observatory
- Royal Observatory, Edinburgh
- r-process
- RR Lyrae star
- RRs variable -> Delta Scuti star
- RR Telescopii star
- RS Canum Venaticorum star
- R star -> carbon star
- Rubin–Ford effect
- runaway star
- rupes
- Henry Norris Russell
- Russell–Vogt theorem -> Vogt–Russell theorem
- RV Tauri star
- RW Aurigae star
- RXTE -> Rossi X-ray Timing Explorer
- Martin Ryle
- Ryle Telescope
S
edit- SAAO -> South African Astronomical Observatory
- Sabik
- Sachs–Wolfe effect
- Sacramento Peak Observatory
- Carl Edward Sagan
- Sagitta (constellation)
- Sagittarius (constellation)
- Sagittarius A
- Sagittarius Arm
- Sagittarius Dwarf Galaxy
- Saha ionization equation
- Sakigake
- Salpeter function -> initial mass function
- Salpeter process -> triple-alpha process
- SALT -> South African Large Telescope
- SAMPEX -> Solar, Anomalous, and Magnetospheric Particle Explorer
- Allan Rex Sandage
- SAO -> Smithsonian Astrophysical Observatory
- SAO Catalog -> Smithsonian Astrophysical Observatory Star Catalog
- saros
- SAS -> Small Astronomy Satellite
- satellite
- Saturn (planet)
- Saturn Nebula
- scale height
- scattered-disk object
- scatter ellipse
- scattering
- Scheat
- Schechter function
- Schedar -> Shedir
- Christoph Scheiner
- Giovanni Virginio Schiaparelli
- schiefspiegler telescope
- Maarten Schmidt
- Schmidt camera
- Schmidt–Cassegrain telescope
- Schönberg–Chandrasekhar limit -> Chandrasekhar–Schönberg limit
- Schröter effect
- (Samuel) Heinrich Schwabe
- Karl Schwarzschild
- Schwarzschild black hole
- Schwarzschild radius
- Schwarzschild telescope
- Comet 29P/Schwassmann–Wachmann 1
- scintillation
- scintillation counter
- S-class asteroid
- Sco-Cen Association
- scopulus
- Scorpius (constellation)
- Scorpius X-1
- Scotch mount
- SC star -> S star
- SCT -> Schmidt–Cassegrain telescope
- Sculptor (constellation)
- Sculptor group
- Scutum (constellation)
- SDO -> Solar Dynamics Observatory
- S Doradus star
- SDSS photometry
- Search for Extraterrestrial Intelligence
- Seashell Galaxy
- season
- (Pietro) Angelo Secchi
- Secchi classification
- second
- leap second
- secondary cosmic ray
- secondary crater
- secondary minimum
- secondary mirror
- second contact
- second of arc
- secular
- secular acceleration
- secular parallax
- secular perturbation
- secular variable
- seeing
- segmented mirror
- selected areas -> Kapteyn Selected Areas
- selective absorption
- Selene (Moon probe)
- selenology
- self-absorption
- semidetached binary
- semidiameter
- semi-forbidden line -> forbidden line
- semimajor axis
- semiregular variable
- sensitivity
- separation
- Serpens (constellation)
- Serrurier truss
- Setebos
- SETI -> Search for Extraterrestrial Intelligence
- setting
- setting circle
- Seven Sisters -> Pleiades
- Sextans (constellation)
- sextant
- Carl Keenan Seyfert
- Seyfert galaxy
- Seyfert's Sextet
- Shack–Hartmann test -> Hartmann test
- shadow bands
- shadow transit
- Shapiro delay
- Harlow Shapley
- Shapley Concentration -> supercluster
- shatter cone
- Shaula
- Shedir
- shell burning
- shell galaxy
- shell star
- shepherd moon
- shergottite
- shield volcano
- shock metamorphism
- Eugene Merle Shoemaker
- Comet Shoemaker–Levy 9 (D/1993 F2)
- shooting star -> meteor
- short-period comet
- short-period variable
- Sickle (asterism)
- side lobe
- sidereal
- sidereal day
- sidereal month
- sidereal period
- sidereal rate
- sidereal time
- sidereal year
- siderite -> iron meteorite
- siderolite -> stony-iron meteorite
- siderophyre
- siderostat
- Siding Spring Observatory
- Sigma Octantis
- signal-to-noise ratio -> sensitivity
- Sikhote–Alin meteorite
- silicon burning
- silicon star
- silvering
- SIMBAD
- SIM PlanetQuest
- single-lined binary
- singularity
- Sinope (moon)
- sinuous rille
- sinus
- SiO maser
- Sirius
- Sirrah
- Willem de Sitter
- SI units
- six-colour system
- 61 Cygni
- SKA -> Square Kilometre Array
- sky brightness
- Skylab
- Earl Carl Slipher
- Vesto Melvin Slipher
- Sloan Digital Sky Survey
- slow nova
- slow pulsator
- SMA -> Submillimeter Array
- Small Astronomy Satellite
- small circle
- Small Magellanic Cloud
- SMART-1
- SMC -> Small Magellanic Cloud
- Smithsonian Astrophysics Observatory
- Smithsonian Astrophysics Observatory Star Catalog
- SMM -> Solar Maximum Mission
- George Fitzgerald Smoot III
- SNC meteorites
- SNR -> supernova remnant
- SNU -> solar neutrino unit
- SOAR -> Southern Astrophysical Research telescope
- SOFIA -> Stratospheric Observatory for Infrared Astronomy
- soft gamma-ray repeater
- soft X-rays
- SO galaxy -> lenticular galaxy
- SOHO -> Solar and Heliospheric Observatory
- Sojourner
- Solar, Anomalous, and Magnetospheric Particle Explorer
- solar activity
- Solar and Heliospheric Observatory
- solar antapex
- solar apex
- solar atmosphere
- solar constant
- solar cycle -> sunspot cycle
- solar day
- Solar Dynamics Observatory
- solar dynamo
- solar eclipse
- solar flare
- solar interior
- solar irradiance
- solar mass
- solar maximum
- Solar Maximum Mission
- solar minimum
- solar motion
- solar nebula
- solar neutrino unit
- Solar Orbiter
- solar oscillations -> helioseismology
- solar parallax
- Solar System
- solar telescope
- solar–terrestrial relations
- Solar Terrestrial Relations Observatory
- solar time
- solar tower
- solar wind
- solar year
- solid Schmidt telescope
- solstice
- solstitial colure
- Sombrero Galaxy
- Sothic cycle
- source count
- South African Astronomical Observatory
- South Atlantic Anomaly
- Southern African Large Telescope
- Southern Astrophysical Research Telescope
- Southern Cross
- southern lights
- Southern Reference Stars
- Southern Sky Survey
- South Pole Aitken Basin
- curvature of space -> curvature of spacetime
- space motion
- space probe
- space reddening -> interstellar absorption
- Space Telescope Science Institute
- spacetime
- space velocity
- Spacewatch
- space weather
- spallation
- spark chamber
- spec. -> speculum metal
- Special Astrophysical Observatory
- special theory of relativity
- speckle interferometry
- spectral classification
- spectral index
- spectral line
- spectral type
- spectrogram
- spectrograph
- spectroheliogram
- spectroheliograph
- spectrohelioscope
- spectrometer
- spectrophotometer
- spectrophotometry
- spectropolarimetry
- spectroscope
- spectroscopic binary
- spectroscopic parallax
- spectroscopy
- spectrum
- 1
- 2
- spectrum binary
- spectrum variable -> Alpha2 Canum Venaticorum
- speculum metal
- Harold Spencer Jones
- spherical aberration
- spherical albedo -> Bond albedo
- spherical astronomy
- spherical coordinates
- spheroid
- Spica
- spicule
- spider
- spin
- spinar
- spin casting
- Spindle Galaxy
- spin-down
- spin–orbit coupling
- spin temperature
- spiral arm
- spiral galaxy
- Spirit (Mars rover)
- Lyman Spitzer, Jr
- Spitzer Space Telescope
- spokes
- sporadic meteor
- Gustav Friedrich Wilhelm Spörer
- Spörer minimum
- Spörer's law
- spray
- spring equinox -> vernal equinox
- Springfield mounting
- spring tide
- s-process
- sputtering
- Square Kilometre Array
- Square of Pegasus
- SS Cygni
- SS Cygni star
- SS433
- S star
- ST -> standard time
- standard atmosphere
- standard epoch
- standard solar model
- standard star
- standard time
- standstill
- star
- starburst galaxy
- star cluster
- star count
- Stardust
- Stark broadening
- starquake
- starspot
- star streaming
- static limit
- static universe
- stationary point
- 1
- 2
- statistical parallax
- steady-state theory
- Stefan–Boltzmann constant
- Stefan–Boltzmann law
- Stefan's law -> Stefan–Boltzmann law
- stellar association
- stellar atmosphere
- stellar evolution
- stellar interferometer
- stellar population
- stellar structure
- stellar wind
- Stephano (moon)
- Stephan's Quintet
- step method -> Argelander step method -> Pogson step method
- steradian
- STEREO -> Solar Terrestrial Relations Observatory
- stereo comparator
- Steward Observatory
- stishovite
- Stokes parameters
- Stonyhurst heliographic coordinates
- stony-iron meteorite
- stony meteorite
- stratigraphy
- stratopause
- stratosphere
- Stratospheric Observatory for Infrared Astronomy
- streamer
- Strehl ratio
- strewn field
- 1
- 2
- string -> cosmic string
- Bengt Georg Daniel Strömgren
- Strömgren photometry
- Strömgren sphere
- strontium star
- Struve
- Friedrich Georg Wilhelm von Struve
- Otto Struve
- Otto Wilhelm Struve
- STScI -> Space Telescope Science Institute
- style
- Subaru Telescope
- subatomic particle -> elementary particle
- subdwarf
- subgiant
- subluminous star
- sublunar point
- Submillimeter Array
- Submillimeter Wave Astronomy Satellite
- submillimetre astronomy
- sub-pulse
- subsolar point
- substellar object
- substellar point
- substorm
- sudden ionospheric disturbance
- Abd al-Raman al-Sufi
- Suisei
- sulcus
- summer solstice -> solstice
- Summer Time
- Summer Triangle
- Sun
- sundial
- sundog -> parhelion
- Sunflower galaxy
- sungrazer -> Kreutz sungrazer
- sunrise
- sunset
- sunskirter
- sunspot
- sunspot cycle
- Sunyaev–Zel'dovich effect
- supercluster
- supergalactic plane
- supergiant
- supergiant elliptical
- supergranulation
- superheterodyne receiver
- superhump -> SU Ursae Majoris star
- superior conjunction
- superior planet
- superluminal velocity
- supermassive black hole
- supermassive star
- supermaximum -> SU Ursae Majoris star
- supernova
- Supernova 1987A
- supernova remnant
- super-rotation
- super-Schmidt telescope
- superstring theory
- supersynthesis
- surface brightness
- surface gravity
- surface temperature
- surge prominence
- Surveyor (space probes)
- SU Ursae Majoris star
- Suzaku
- S Vulpeculae star
- Swan bands
- Swan Nebula -> Omega Nebula
- SWAS -> Submillimeter Wave Astronomy Satellite
- Swift (satellite)
- Comet 109P/Swift–Tuttle
- Sword Hand of Perseus
- Sword of Orion
- SX Arietis star
- SX Phoenicis star
- Sycorax (moon)
- symbiotic star
- synchronous orbit
- synchronous rotation
- syndyname
- synodic
- synodic month
- synodic period
- Syrtis Major
- Systems I, II, and III
- syzygy
T
edit- tachocline
- tachyon
- TAI -> Temps Atomique International -> International Atomic Time
- cometary tail
- tangential velocity
- Tarantula Nebula
- Tarazed
- T association
- Taurid meteors
- Taurus
- Taurus A
- Taurus Molecular Clouds
- Taurus Moving Cluster
- Taurus X-1
- TCB -> Barycentric Coordinate Time
- T-class asteroid
- TDB -> Temps Dynamique Barycentrique -> Barycentric Dynamical Time
- T dwarf
- Teapot (asterism)
- Comet Tebbutt (C/1861 J1)
- technetium star
- tectonics
- Teide Observatory
- tektite
- telecompressor
- tele-extender
- telescope
- telescope drive -> drive
- telescope mounting -> mounting
- Telescopio Nazionale Galileo
- Telescopium (constellation)
- Telesto
- telluric lines
- tellurium
- Comet 55P/Tempel–Tuttle
- temperature
- temperature minimum
- Tenma
- termination shock
- terminator
- terra
- terracing
- terrestrial age
- Terrestrial Dynamical Time -> Terrestrial Time
- terrestrial planet
- Terrestrial Time
- tesla
- tessera
- Tethys (moon)
- Thalassa (moon)
- Thales of Miletus
- Tharsis Montes
- Thebe (moon)
- Themis family
- Themisto (moon)
- theory of everything -> grand unified theory
- thermal bremsstrahlung -> free–free transition
- thermal equilibrium
- 1
- 2
- thermal radiation
- thermocouple
- thermodynamic equilibrium -> thermal equilibrium
- thermodynamic temperature
- thermopile
- thermosphere
- thinned chip
- Third Cambridge Catalogue
- third contact
- third quarter -> last quarter
- 30 Doradus -> Tarantula Nebula
- Thirty Meter Telescope
- tholus
- William Thomson -> Lord Kelvin
- Thomson scattering
- three-body problem
- three-colour photography -> astrophotography
- three-colour photometry -> Johnson photometry
- three-kiloparsec arm
- Thuban
- Thule (asteroid)
- tidal bulge
- tidal evolution
- tidal force
- tidal friction
- tidal heating
- tides
- time
- time dilation
- time of perihelion passage
- time zone
- TiO bands
- tip–tilt mirror
- Tisserand parameter
- Titan (moon)
- Titania (moon)
- Titius–Bode law -> Bode's law
- TLP -> lunar transient phenomenon
- TMT -> Thirty Meter Telescope
- TNG -> Galileo National Telescope
- TNO -> trans-Neptunian object
- Toby Jug Nebula
- Tolman test
- Clyde William Tombaugh
- topocentric
- topocentric coordinates
- Torino scale
- Toro (asteroid)
- torquetum
- torus
- total eclipse
- totality
- total magnitude -> integrated magnitude
- total solar irradiance
- Toutatis (asteroid)
- TRACE -> Transition Region and Coronal Explorer
- train (meteors)
- transfer function
- transfer lens
- transfer orbit
- transient lunar phenomenon -> lunar transient phenomenon
- meridian transit
- planetary transit
- transit circle
- transit instrument
- transition probability
- transition region
- Transition Region and Coronal Explorer
- transmission grating
- trans-Neptunian object
- atmospheric transparency
- transverse velocity -> tangential velocity
- Trapezium (star)
- Triangulum (constellation)
- Triangulum Australe (constellation)
- Triangulum Galaxy
- Trifid Nebula
- trigonometric parallax
- triple-alpha process
- triplet (lens)
- triquetrum
- trischiefspiegler -> schiefspiegler telescope
- Triton (moon)
- Trojan asteroid
- tropic
- tropical month
- tropical period
- tropical year
- Tropic of Cancer
- Tropic of Capricorn
- tropopause
- troposphere
- true anomaly
- true equator
- true equinox
- true pole
- Trumpler classification
- Trumpler star
- TT -> Terrestrial Time
- T Tauri star
- T Tauri wind
- Tucana (constellation)
- Tully–Fischer relation
- Tunguska event
- tuning-fork diagram
- atmospheric turbulence
- turnoff point
- Nasir al-Din al-Tusi
- Comet 41P/Tuttle–Giacobini–Kresák
- 21-centimetre line
- twilight
- twinkling
- two-body problem
- two-colour diagram
- two-colour photometry -> BV photometry
- Two-Micron All-Sky Survey
- two-spectrum binary -> composite-spectrum binary
- Tycho Brahe
- Tycho Catalogue
- Tychonic system
- Tycho's Star
- Type I supernova -> supernova
- Type II supernova -> supernova
U
edit- UBV photometry -> Johnson photometry
- UBVRIJKL photometry -> Johnson photometry
- U-class asteroid
- U Geminorum star
- Uhuru
- UKIDSS -> UKIRT Infrared Deep-Sky Survey
- UKIDSS photometry
- UKIRT -> United Kingdom Infrared Telescope
- UKIRT Infrared Deep-Sky Survey
- UKST -> United Kingdom Schmidt Telescope
- ultra-compact dwarf galaxy
- ultra-luminous infrared galaxy
- ultraviolet astronomy
- ultraviolet excess star
- ultraviolet photometry
- ultraviolet radiation
- Ulugh Beg
- Ulysses (spacecraft)
- U magnitude
- umbra
- 1
- 2
- Umbriel (moon)
- undae
- undersampling
- Undina family
- unfilled aperture
- unit distance
- United Kingdom Infrared Telescope
- United Kingdom Schmidt Telescope
- Universal Time
- Universe
- unsharp masking
- upper culmination -> culmination
- Upsilon Sagittarii star
- Uranometria
- Uranus
- Urca process
- ureilite
- Harold Clayton Urey
- Ursa Major
- Ursa Major Moving Cluster
- Ursa Minor
- Ursid meteors
- US Naval Observatory
- USNO CCD Astrograph Catalog
- UT -> Universal Time
- UTC -> Universel Temps Coordonné -> Coordinated Universal Time
- Utopia Planitia
- UU Herculis star
- UV -> ultraviolet
- uvby system -> Strömgren photometry
- UV Ceti star
- UV Persei star
- UXor -> UX Orionis star
- UX Orionis star
- UX Ursae Majoris star
V
edit- vacuum energy
- Valhalla (impact basin)
- Valles Marineris
- vallis
- James Alfred Van Allen
- Van Allen Belts
- Van Biesbroeck's Star
- Hendrik van de Hulst
- van Maanen's Star
- variable star
- variation
- 1
- 2
- variation of latitude -> latitude variation
- vastitas
- Vatican Advanced Technology Telescope
- VBLUW photometry -> Walraven photometry
- V-class asteroid
- Vega (star)
- Vega probes
- Veil Nebula
- Vela (constellation)
- Vela pulsar
- Vela Supernova Remnant
- velocity curve
- velocity dispersion
- velocity–distance relation
- Venera
- Venus (planet)
- Venus Express
- VERITAS -> Very Energetic Radiation Imaging Telescope Array System
- vernal equinox
- vertical circle
- Very Energetic Radiation Imaging Telescope Array System
- Very Large Array
- Very Large Telescope
- Very Long Baseline Array
- very long baseline interferometry
- very slow nova -> RR Telescopii star
- Very Small Array
- Vesta (asteroid)
- Viking (space probes)
- VILGEN photometry
- Vilnius photometry
- violent relaxation
- virga
- Virginid meteors
- Virgo (constellation)
- Virgo A
- Virgo Cluster
- Virgo Supercluster -> local supercluster
- virial theorem
- Virtual Observatory
- virtual particle
- Visible and Infrared Survey Telescope for Astronomy
- VISTA -> Visible and Infrared Survey Telescope for Astronomy
- visual binary
- visual magnitude
- VLA -> Very Large Array
- VLBA -> Very Long Baseline Array
- VLBI -> very long baseline interferometry
- VLBI Space Observatory Programme
- VLT -> Very Large Telescope
- V magnitude
- Hermann Carl Vogt
- Vogt–Russell theorem
- void
- Voigt profile
- Volans
- volatile
- von Zeipel theorem
- Voyager (space probes)
- VSOP -> VLBI Space Observatory Programme
- Vulcan (hypothetical planet)
- Vulpecula (constellation)
- VV Cephei star -> Zeta Aurigae star
- VV Sculptoris star
W
edit- walled plain
- Walraven photometry
- waning
- Washington Double Star Catalog
- Water Jar
- water maser -> H2O maser
- water of hydration
- wavefront
- waveguide
- wavelength
- wavenumber
- wave plate
- waxing
- WC star -> Wolf–Rayet star
- WDS -> Washington Double Star Catalog
- weber
- weird terrain
- Carl Friedrich von Weizsäcker
- Werner lines
- Comet West (C/1975 V1)
- Westerbork Radio Observatory
- Wezen
- Fred Lawrence Whipple
- Whipple Observatory -> Fred Lawrence Whipple Observatory
- Whirlpool Galaxy
- whistler
- white dwarf
- white hole
- white-light corona
- WHT -> William Herschel Telescope
- Wide Field Infrared Survey Explorer
- Widmanstätten pattern
- Wielen dip
- Wien's displacement law
- Wild Duck Cluster
- Wild's Triplet
- Rupert Wildt
- Wilkinson Microwave Anisotropy Probe
- William Herschel Telescope
- Robert Woodrow Wilson
- Wilson–Bappu effect
- Wilson effect
- Comet 107P/Wilson–Harrington
- WIMP
- Wind (satellite)
- winter solstice -> solstice
- WISE -> Wide Field Infrared Survey Explorer
- WIYN Telescope
- WMAP -> Wilkinson Microwave Anisotropy Probe
- W. M. Keck Observatory
- WN star -> Wolf–Rayet star
- Maximilian ('Max') Franz Joseph Cornelius
- (Johann) Rudolf Wolf
- Wolf diagram
- Wolf–Lundmark–Melotte system
- Wolf–Rayet star
- Wolf sunspot number
- Wolf 359
- Wollaston prism
- Wolter telescope
- Richard van der Riet Woolley
- world line
- wormhole
- Wright telescope
- wrinkle ridge
- WR star -> Wolf–Rayet star
- W Serpentis star -> Algol star
- W Ursae Majoris star
- W Virginis star
- Wyoming Infrared Observatory
- WZ Sagittae star
X
editY
editZ
edit- z -> redshift
- ZAMS -> zero-age main sequence
- Z Andromedae star
- Zanstra method
- ZC -> Zodiacal Catalogue
- Z Camelopardalis star
- ZD -> zenith distance
- Zeeman effect
- Zelenchukskaya
- zenith
- zenithal attraction
- zenithal hourly rate
- zenith distance
- zenith telescope
- zero-age horizontal branch
- zero-age main sequence
- Zeta Aurigae star
- ZHR -> zenithal hourly rate
- zirconium star -> S star
- Z magnitude
- zodiac
- Zodiacal Catalogue
- zodiacal dust
- zodiacal light
- Zond
- zone catalogue
- zone of avoidance
- zone time
- Zubenelgenubi
- Zürich relative sunspot number -> relative sunspot number
- Fritz Zwicky
- Zwicky Catalogue
- ZZ Ceti star
Feature entries
editA2
edit- Talk:Å -> Talk:angstrom
- Talk:AAO -> Talk:Anglo-Australian Observatory
- Talk:AAS -> Talk:American Astronomical Society
- Talk:AAT -> Talk:Anglo-Australian Telescope
- Talk:AAVSO -> Talk:American Association of Variable Star Observers
- Talk:A band
- Talk:Abell Catalogue
- Talk:Abell cluster
- Talk:Abell radius
- Talk:constant of aberration -> Talk:annual aberration
- Talk:optical aberration
- Talk:aberration of starlight
- Talk:ablation
- Talk:ablation age
- Talk:absolute magnitude
- Talk:1
- Talk:2
- Talk:absolute temperature -> Talk:thermodynamic temperature
- Talk:absolute zero
- Talk:absorption
- Talk:absorption coefficient
- Talk:absorption edge
- Talk:absorption line
- Talk:absorption nebula -> Talk:dark nebula
- Talk:absorption spectrum
- Talk:abundance -> Talk:abundance of elements
- Talk:Acamar
- Talk:acceleration of free fall
- Talk:accretion
- Talk:accretion disk
- Talk:ACE -> Talk:Advanced Composition Explorer
- Talk:Achernar
- Talk:Achilles
- Talk:achondrite
- Talk:achromatic
- Talk:achromatism
- Talk:A-class asteroid
- Talk:acronical
- Talk:Acrux -> Talk:Alpha Crucis
- Talk:active galactic nucleus
- Talk:active optics
- Talk:active prominence
- Talk:active region
- Talk:John Couch Adams
- Talk:Walter Sydney Adams
- Talk:Adams Ring
- Talk:adaptive optics
- Talk:Adhara
- Talk:adiabatic process
- Talk:Adonis
- Talk:Adrastea (moon)
- Talk:ADS -> Talk:Aitken Double Star Catalogue
- Talk:Advanced Composition Explorer
- Talk:ACE
- Talk:advance of perihelion
- Talk:advection
- Talk:aeon
- Talk:aerial -> Talk:antenna
- Talk:aerobraking
- Talk:aerolite -> Talk:stony meteorite
- Talk:aeronomy
- Talk:aerosol
- Talk:Ae star
- Talk:aether -> Talk:ether
- Talk:afocal
- Talk:afterglow
- Talk:AGB star -> Talk:asymptotic giant branch star
- Talk:Agena -> Talk:Hadar -> Talk:Beta Centauri
- Talk:agglutinate
- Talk:AGILE
- Talk:AGK
- Talk:AGN -> Talk:active galactic nucleus
- Talk:Ahnighito meteorite -> Talk:Cape York meteorite
- Talk:airglow
- Talk:airmass
- Talk:air shower -> Talk:cosmic-ray shower
- Talk:George Biddell Airy
- Talk:Airy disk
- Talk:Robert Grant Aitken
- Talk:Aitken Double Star Catalogue
- Talk:AI Velorum star
- Talk:AJ -> Talk:Astronomical Journal
- Talk:Akari
- Talk:Albategnius -> Talk:al-Battani
- Talk:al-Battani -> Talk:Battani
- Talk:albedo
- Talk:albedo feature
- Talk:Albireo
- Talk:Alcor
- Talk:Alcyone
- Talk:Aldebaran
- Talk:Alderamin
- Talk:Alexandra family
- Talk:ALEXIS
- Talk:Hannes Olof Gösta Alfvén
- Talk:Alfvén surface
- Talk:Alfvén wave
- Talk:Algenib
- Talk:Algieba
- Talk:Algol
- Talk:Algol star
- Talk:Algonquin Radio Observatory
- Talk:Alhena
- Talk:aliasing
- Talk:alidade
- Talk:Alioth
- Talk:Alkaid
- Talk:Allegheny Observatory
- Talk:Allende meteorite
- Talk:Allen Telescope Array
- Talk:all-sky camera
- Talk:ALMA -> Talk:Atacama Large Millimeter Array
- Talk:Almaak
- Talk:Almagest
- Talk:almanac
- Talk:almucantar
- Talk:Alnair
- Talk:Alnath
- Talk:Alnilam
- Talk:Alnitak
- Talk:α -> Talk:right ascension
- Talk:Alpha Capricornid meteors
- Talk:Alpha Centauri
- Talk:Alpha Crucis
- Talk:Alpha Cygnid meteors
- Talk:Alpha Cygni star
- Talk:alpha particle
- Talk:Alphard
- Talk:Alpha Scorpiid meteors
- Talk:Alpha2 Canum Venaticorum star
- Talk:Alphekka
- Talk:Alpheratz
- Talk:Alrescha
- Talk:Alshain
- Talk:al-Sufi -> Talk:Sufi
- Talk:Altair
- Talk:altazimuth mounting
- Talk:altitude
- Talk:al-Tusi -> Talk:Tusi
- Talk:aluminizing
- Talk:Amalthea
- Talk:Viktor Amazaspovich Ambartsumian
- Talk:ambipolar diffusion
- Talk:AM Canum Venaticorum star
- Talk:American Association of Variable Star Observers
- Talk:American Astronomical Society
- Talk:Ames Research Center
- Talk:AM Herculis star
- Talk:Amor group
- Talk:amplitude
- Talk:1
- Talk:2
- Talk:Am star
- Talk:anaemic spiral galaxy
- Talk:analemma
- Talk:Ananke
- Talk:anastigmatic
- Talk:Anaxagoras
- Talk:Anaximander
- Talk:Andromeda
- Talk:Andromeda Galaxy
- Talk:Andromedid meteors
- Talk:Anglo-Australian Observatory
- Talk:Anglo-Australian Telescope
- Talk:Anders Jonas Ångström
- Talk:angstrom
- Talk:angular acceleration
- Talk:angular diameter
- Talk:angular distance -> Talk:angular separation
- Talk:angular momentum
- Talk:angular resolution
- Talk:angular separation
- Talk:angular velocity
- Talk:anisotropy
- Talk:Ankaa
- Talk:annealing
- Talk:annual aberration
- Talk:annual equation
- Talk:annual inequality -> Talk:annual equation
- Talk:annual parallax
- Talk:annual variation
- Talk:annular eclipse
- Talk:anomalistic month
- Talk:anomalistic year
- Talk:anomalous Cepheid
- Talk:anomalous iron
- Talk:anomaly
- Talk:anorthosite
- Talk:ANS -> Talk:Astronomical Netherlands Satellite
- Talk:ansa
- Talk:ansae
- Talk:antapex -> Talk:solar apex
- Talk:Antares
- Talk:antenna
- Talk:Antennae
- Talk:antenna pattern
- Talk:antenna temperature
- Talk:anthelion
- Talk:anthelion radiant
- Talk:anthropic principle
- Talk:anticentre -> Talk:galactic anticentre
- Talk:anti-dwarf nova
- Talk:antimatter
- Talk:antitail
- Talk:Antlia
- Talk:Eugène Michael Antoniadi
- Talk:Antoniadi scale
- Talk:Antu
- Talk:ap-
- Talk:apo-
- Talk:Apache Point Observatory
- Talk:apastron
- Talk:aperture
- Talk:aperture efficiency
- Talk:aperture ratio
- Talk:aperture synthesis
- Talk:APEX -> Talk:Atacama Pathfinder Experiment
- Talk:apex -> Talk:solar apex
- Talk:aphelion
- Talk:Aphrodite Terra
- Talk:ApJ -> Talk:Astrophysical Journal
- Talk:aplanatic
- Talk:apoapsis
- Talk:apocentre
- Talk:apochromatic
- Talk:apodization
- Talk:apogee
- Talk:apohele
- Talk:Apollo group
- Talk:Apollonius of Perga
- Talk:Apollo project
- Talk:apparent diameter -> Talk:angular diameter
- Talk:apparent magnitude
- Talk:apparent noon
- Talk:apparent place
- Talk:apparent retrogression
- Talk:apparent sidereal time
- Talk:apparent solar time
- Talk:apparition
- Talk:appulse
- Talk:apse -> Talk:apsides
- Talk:apsis -> Talk:apsides
- Talk:apsidal motion
- Talk:apsides
- Talk:Ap star
- Talk:Apus
- Talk:Aquarid meteors
- Talk:Aquarius
- Talk:aqueous alteration
- Talk:Aquila
- Talk:Ara
- Talk:arachnoid
- Talk:François Arago
- Talk:Dominique François Jean Arago
- Talk:Arago ring
- Talk:arc
- Talk:archaeoastronomy
- Talk:arch filament system
- Talk:arc minute -> Talk:minute of arc
- Talk:arcmin -> Talk:minute of arc
- Talk:arc second -> Talk:second of arc
- Talk:arcsec -> Talk:second of arc
- Talk:Arcturus
- Talk:arcus
- Talk:area photometer
- Talk:Arecibo Observatory
- Talk:Comet Arend–Roland (C/1956 R1)
- Talk:areo-
- Talk:Friedrich Wilhelm August Argelander
- Talk:Argelander step method
- Talk:Argo Navis
- Talk:argon–potassium method -> Talk:potassium–argon method
- Talk:argument of perihelion
- Talk:Argyre Planitia
- Talk:Ariel
- Talk:Ariel satellites
- Talk:Aries
- Talk:first point of Aries
- Talk:Aristarchos Telescope
- Talk:Aristarchus of Samos
- Talk:Aristotle
- Talk:Arizona meteor crater -> Talk:meteor crater
- Talk:Arizona Radio Observatory
- Talk:ARO
- Talk:AR Lacertae star
- Talk:armillary sphere
- Talk:arm population
- Talk:Arneb
- Talk:array
- Talk:1
- Talk:2
- Talk:artificial satellite
- Talk:ASCA
- Talk:ascending node
- Talk:Asclepius
- Talk:ashen light
- Talk:ASP -> Talk:Astronomical Society of the Pacific
- Talk:aspect
- Talk:aspheric
- Talk:stellar association
- Talk:Association of Universities for Research in Astronomy
- Talk:AURA
- Talk:A star
- Talk:asterism
- Talk:asteroid
- Talk:asteroid belt
- Talk:asteroseismology
- Talk:asthenosphere
- Talk:astigmatism
- Talk:Astraea
- Talk:astration
- Talk:astrobiology
- Talk:astrobleme
- Talk:astrochemistry
- Talk:astrodynamics
- Talk:astrograph
- Talk:Astrographic Catalogue
- Talk:astrolabe
- Talk:astrology
- Talk:astrometric binary
- Talk:astrometry
- Talk:astronavigation
- Talk:Astronomer Royal
- Talk:Astronomer Royal for Scotland
- Talk:The Astronomical Almanac
- Talk:Astronomical Journal
- Talk:AJ
- Talk:Astronomical Netherlands Satellite
- Talk:ANS
- Talk:Astronomical Society of the Pacific
- Talk:ASP
- Talk:astronomical triangle
- Talk:astronomical twilight
- Talk:astronomical unit
- Talk:AU
- Talk:astronomy
- Talk:Astronomy and Astrophysics
- Talk:A&A -> Talk:Astronomy and Astrophysics
- Talk:astrophotography
- Talk:Astrophysical Journal
- Talk:astrophysics
- Talk:ASTROSAT
- Talk:astrum
- Talk:Asuka -> Talk:ASCA
- Talk:asymptotic giant branch star
- Talk:AGB star
- Talk:Atacama Large Millimeter Array
- Talk:ALMA
- Talk:Atacama Pathfinder Experiment
- Talk:APEX
- Talk:ataxite
- Talk:Aten group
- Talk:Atlas
- Talk:atmosphere
- Talk:atmospheric extinction
- Talk:atmospheric refraction
- Talk:atmospheric scattering -> Talk:atmospheric extinction -> Talk:Mie scattering -> Talk:Rayleigh scattering
- Talk:atmospheric window
- Talk:ATNF -> Talk:Australia Telescope National Facility
- Talk:atom
- Talk:atomic clock
- Talk:atomic time
- Talk:Atria
- Talk:attenuation
- Talk:1
- Talk:2
- Talk:AU -> Talk:astronomical unit
- Talk:aubrite
- Talk:Auger shower -> Talk:cosmic-ray shower
- Talk:augmentation
- Talk:AURA -> Talk:Association of Universities for Research in Astronomy
- Talk:Auriga
- Talk:Aurora programme
- Talk:aurora
- Talk:auroral oval
- Talk:auroral substorm -> Talk:substorm
- Talk:Australia Telescope National Facility
- Talk:ATNF
- Talk:australite
- Talk:autocorrelation
- Talk:autocorrelator
- Talk:autoguider
- Talk:autoionization
- Talk:autumnal equinox -> Talk:equinox
- Talk:averted vision
- Talk:Avior
- Talk:axion
- Talk:optical axis
- Talk:axis of rotation
- Talk:azimuth
- Talk:Azophi -> Talk:al-Sufi
B2
edit- Talk:BAA -> Talk:British Astronomical Association
- Talk:Wilhelm Heinrich Walter Baade
- Talk:Walter Baade
- Talk:Baade's Window
- Talk:Baade–Wesselink method
- Talk:Harold Delos Babcock
- Talk:Horace Welcome Babcock
- Talk:background noise
- Talk:background radiation
- Talk:backscattering
- Talk:Bailey type
- Talk:Francis Baily
- Talk:Baily's beads
- Talk:Baker–Schmidt telescope
- Talk:Baldwin effect
- Talk:Balmer limit
- Talk:Balmer lines -> Talk:Balmer series
- Talk:Balmer series
- Talk:band
- Talk:bandpass filter
- Talk:bandwidth
- Talk:bar
- Talk:barium star
- Talk:Barlow lens
- Talk:Edward Emerson Barnard
- Talk:Barnard's Loop
- Talk:Barnard's Star
- Talk:barn-door mount -> Talk:Scotch mount
- Talk:Barnes–Evans relationship
- Talk:barred spiral galaxy
- Talk:barrel distortion
- Talk:Barringer Crater -> Talk:meteor crater
- Talk:barycentre
- Talk:Barycentric Celestial Reference System
- Talk:barycentric coordinates
- Talk:Barycentric Coordinate Time
- Talk:Barycentric Dynamical Time
- Talk:baryon
- Talk:baryon star
- Talk:basalt
- Talk:basaltic achondrite
- Talk:baseline
- Talk:impact basin
- Talk:Muammad ibn Jabir al-Battani
- Talk:Ba II star -> Talk:barium star
- Talk:Bautz–Morgan class
- Talk:Johann Bayer
- Talk:Bayer letters
- Talk:B band
- Talk:B-class asteroid
- Talk:BCRS -> Talk:Barycentric Celestial Reference System
- Talk:BD -> Talk:Bonner Durchmusterung
- Talk:Beagle
- Talk:beam
- Talk:beaming
- Talk:beamwidth
- Talk:beat Cepheid
- Talk:Becklin–Neugebauer Object (BN Object)
- Talk:Becrux -> Talk:Beta Crucis
- Talk:bediasite
- Talk:Beehive Cluster -> Talk:Praesepe
- Talk:Belinda
- Talk:Bellatrix
- Talk:Susan Jocelyn Bell Burnell
- Talk:Jocelyn Bell Burnell
- Talk:Belt of Orion
- Talk:Benetnasch -> Talk:Alkaid
- Talk:Comet Bennett (C/1969 Y1)
- Talk:bent-pillar mounting
- Talk:BepiColombo
- Talk:BeppoSAX
- Talk:Berkeley–Illinois–Maryland Association Array (BIMA Array)
- Talk:Friedrich Wilhelm Bessel
- Talk:Besselian day numbers
- Talk:Besselian elements
- Talk:Besselian epoch
- Talk:Besselian year
- Talk:Be star
- Talk:B(e) star
- Talk:Beta Canis Majoris star -> Talk:Beta Cephei star
- Talk:Beta Cephei star
- Talk:Beta Crucis
- Talk:beta decay
- Talk:Beta Lyrae star
- Talk:beta particle
- Talk:Beta Persei star -> Talk:Algol star
- Talk:Beta Pictoris
- Talk:Beta Regio
- Talk:Beta Taurid meteors
- Talk:Betelgeuse
- Talk:Hans Albrecht Bethe
- Talk:Bethe–Weizsäcker cycle -> Talk:carbon–nitrogen cycle
- Talk:Bianca
- Talk:Bianchi cosmology
- Talk:biconcave lens
- Talk:biconvex lens
- Talk:Comet 3D/Biela
- Talk:Bielid meteors -> Talk:Andromedid meteors
- Talk:Big Bang theory
- Talk:Big Bear Solar Observatory
- Talk:Big Crunch
- Talk:Big Dipper
- Talk:billitonite
- Talk:BIMA Array
- Talk:binary galaxy
- Talk:binary pulsar
- Talk:binary star
- Talk:binding energy
- Talk:binoculars
- Talk:Jean-Baptiste Biot
- Talk:bipolar group
- Talk:bipolar nebula
- Talk:bipolar outflow
- Talk:birefringent filter
- Talk:Birmingham Solar Oscillations Network
- Talk:BiSON -> Talk:Birmingham Solar Oscillations Network
- Talk:black body
- Talk:black-body radiation
- Talk:black drop
- Talk:black dwarf
- Talk:Black Eye Galaxy
- Talk:black hole
- Talk:Black Widow Pulsar -> Talk:binary pulsar
- Talk:blazar
- Talk:Blaze Star
- Talk:Blazhko effect
- Talk:BL Herculis star
- Talk:blink comparator
- Talk:Blinking Planetary
- Talk:BL Lacertae object
- Talk:BL Lac object
- Talk:bloomed lens
- Talk:blooming
- Talk:1
- Talk:2
- Talk:blue clearing
- Talk:blue compact dwarf galaxy
- Talk:blue giant
- Talk:blue Moon
- Talk:1
- Talk:2
- Talk:Blue Planetary
- Talk:blue populous cluster -> Talk:Large Magellanic Cloud
- Talk:blueshift
- Talk:blue straggler
- Talk:B magnitude
- Talk:BN Object -> Talk:Becklin–Neugebauer Object
- Talk:Johann Elert Bode
- Talk:Bode's law
- Talk:Bartholomeus Jan Bok
- Talk:Bartholomeus 'Bart' Jan Bok
- Talk:Bok globule -> Talk:globule
- Talk:bolide
- Talk:bolometer
- Talk:bolometric correction
- Talk:bolometric magnitude
- Talk:Boltzmann constant
- Talk:George Phillips Bond
- Talk:William Cranch Bond
- Talk:Bond albedo
- Talk:Hermann Bondi
- Talk:Bonner Durchmusterung
- Talk:Boötes
- Talk:boson
- Talk:Boss General Catalogue
- Talk:GC
- Talk:boundary layer
- Talk:bound–bound transition
- Talk:bound–free transition
- Talk:Bouwers telescope
- Talk:Ira Sprague Bowen
- Talk:Bowen fluorescence
- Talk:bow shock
- Talk:Bp star
- Talk:Brackett series
- Talk:James Bradley
- Talk:Bragg crystal spectrometer
- Talk:Tycho Brahe
- Talk:Brans–Dicke theory
- Talk:breccia
- Talk:bremsstrahlung
- Talk:bridge (astronomy)
- Talk:bright nebula
- Talk:brightness temperature
- Talk:Bright Star Catalogue
- Talk:British Astronomical Association
- Talk:broad-band photometry
- Talk:Brocchi's Cluster
- Talk:Comet 16P/Brooks 2 -> Talk:Jupiter comet family
- Talk:Ernest William Brown
- Talk:brown dwarf
- Talk:B star
- Talk:Bubble Nebula
- Talk:Budrosa family
- Talk:Bug Nebula
- Talk:bump Cepheid
- Talk:Geoffrey Ronald Burbidge
- Talk:Eleanor Margaret Burbidge
- Talk:burst (astronomy)
- Talk:Butcher–Oemler effect
- Talk:Butler matrix
- Talk:Butterfly Cluster
- Talk:butterfly diagram
- Talk:Butterfly Nebula
- Talk:BV photometry
- Talk:Bw star
- Talk:BY Draconis star
- Talk:Byurakan Astrophysical Observatory
C2
edit- Talk:Caelum
- Talk:Calar Alto Observatory
- Talk:caldera
- Talk:calendar
- Talk:calendar year
- Talk:Caliban
- Talk:California Nebula
- Talk:Callippus
- Talk:Callisto
- Talk:Caloris Basin
- Talk:Caltech Submillimeter Observatory
- Talk:CSO
- Talk:Calypso (moon)
- Talk:Cambridge Optical Aperture Synthesis Telescope
- Talk:COAST
- Talk:Camelopardalis
- Talk:William Wallace Campbell
- Talk:Canada–France–Hawaii Telescope
- Talk:canale
- Talk:canali
- Talk:Martian canals
- Talk:Cancer
- Talk:Tropic of Cancer
- Talk:Canes Venatici
- Talk:Canis Major
- Talk:Canis Minor
- Talk:Annie Jump Cannon
- Talk:Canopus
- Talk:cantaloupe terrain
- Talk:Capella
- Talk:Cape Photographic Durchmusterung
- Talk:Cape photometry
- Talk:Cape RI photometry -> Talk:Kron–Cousins RI photometry
- Talk:Cape York meteorite
- Talk:Caph
- Talk:Tropic of Capricorn
- Talk:Capricornid meteors
- Talk:Capricornus
- Talk:captured rotation -> Talk:synchronous rotation
- Talk:Carafe Galaxy
- Talk:carbonaceous chondrite
- Talk:carbon burning
- Talk:carbon cycle -> Talk:carbon–nitrogen cycle
- Talk:carbon flash
- Talk:carbon–nitrogen cycle (CN cycle)
- Talk:carbon star
- Talk:Carina
- Talk:Carina Arm
- Talk:Carina Dwarf Galaxy
- Talk:Carina–Sagittarius Arm
- Talk:CARMA -> Talk:Combined Array for Research in Millimeter-wave Astronomy
- Talk:Carme
- Talk:Carnegie Observatories
- Talk:Carpo
- Talk:Richard Christopher Carrington
- Talk:Carrington heliographic coordinates
- Talk:Carrington rotation
- Talk:Carte du Ciel
- Talk:Cartesian coordinates
- Talk:Cartwheel Galaxy
- Talk:Cassegrain telescope
- Talk:Cassini
- Talk:Giovanni Domenico Cassini
- Talk:Jacques Cassini
- Talk:Cassini Division
- Talk:Cassini–Huygens
- Talk:Cassiopeia
- Talk:Cassiopeia A
- Talk:Castalia
- Talk:Castor
- Talk:cataclysmic binary
- Talk:cataclysmic variable
- Talk:catadioptric system
- Talk:Catalina Sky Survey
- Talk:catalogue equinox
- Talk:catena
- Talk:catoptric system
- Talk:Cat's Eye Nebula
- Talk:cavus
- Talk:CCD -> Talk:charge-coupled device
- Talk:CCD spectrometer
- Talk:C-class asteroid
- Talk:cD Galaxy
- Talk:CDM -> Talk:cold dark matter
- Talk:CDS -> Talk:Centre de Données astronomiques de Strasbourg
- Talk:celestial axis
- Talk:celestial coordinates
- Talk:celestial equator
- Talk:Celestial Intermediate Reference System
- Talk:celestial latitude
- Talk:celestial longitude
- Talk:celestial mechanics
- Talk:celestial meridian
- Talk:celestial pole
- Talk:celestial sphere
- Talk:Centaur group
- Talk:Centaurus
- Talk:Centaurus A
- Talk:Center for Astrophysics
- Talk:Central Bureau for Astronomical Telegrams
- Talk:central meridian
- Talk:central peak
- Talk:Centre de Données astronomiques de Strasbourg
- Talk:centre of gravity
- Talk:centre of inertia
- Talk:centre of mass
- Talk:centrifugal force
- Talk:centripetal force
- Talk:Cepheid instability strip
- Talk:Cepheid variable
- Talk:Cepheus
- Talk:Cerenkov counter
- Talk:Cerenkov radiation
- Talk:Ceres
- Talk:Cerro Pachón
- Talk:Cerro Paranal
- Talk:Cerro Tololo Inter-American Observatory
- Talk:Cetus
- Talk:CfA -> Talk:Harvard–Smithsonian Center for Astrophysics
- Talk:CGRO -> Talk:Compton Gamma Ray Observatory
- Talk:Chamaeleon
- Talk:Chandler period
- Talk:Chandler wobble
- Talk:Subrahmanyan Chandrasekhar
- Talk:Chandrasekhar limit
- Talk:Chandrasekhar-Schönberg limit
- Talk:Chandra X-ray Observatory
- Talk:Chandrayaan-1
- Talk:Chang'e
- Talk:chaos
- Talk:chaotic orbit
- Talk:chaotic terrain
- Talk:CHARA Array
- Talk:charge
- Talk:charge-coupled device
- Talk:Charon
- Talk:chasma
- Talk:chassignite
- Talk:chemical element
- Talk:chemosphere
- Talk:Chicxulub
- Talk:CHIPSat
- Talk:Chiron
- Talk:Ernst Florens Friedrich Chladni
- Talk:chondrite
- Talk:chondrule
- Talk:chopper
- Talk:chopping secondary
- Talk:William Henry Mahoney Christie
- Talk:chromatic aberration
- Talk:chromosphere
- Talk:chromospheric network
- Talk:Chryse Planitia
- Talk:CH star
- Talk:Circinus
- Talk:Circlet
- Talk:circular velocity
- Talk:circumpolar
- Talk:circumstellar maser
- Talk:circumstellar matter
- Talk:Cirrus Nebula -> Talk:Veil Nebula
- Talk:CIRS -> Talk:Celestial Intermediate Reference System
- Talk:cislunar
- Talk:civil time
- Talk:civil twilight
- Talk:civil year
- Talk:Alexis Claude Clairaut
- Talk:Alvan Clark
- Talk:classical Cepheid
- Talk:clast
- Talk:clathrate
- Talk:CLEAN
- Talk:Clementine
- Talk:James Clerk Maxwell
- Talk:C line
- Talk:clock drive -> Talk:drive
- Talk:clock star
- Talk:closed universe
- Talk:Clown Face Nebula -> Talk:Eskimo Nebula
- Talk:Cluster
- Talk:star cluster -> Talk:globular cluster
- Talk:star cluster -> Talk:open cluster
- Talk:cluster, star -> Talk:star cluster
- Talk:cluster of galaxies
- Talk:cluster variable -> Talk:RR Lyrae star
- Talk:CMB -> Talk:cosmic microwave background
- Talk:CME -> Talk:coronal mass ejection
- Talk:CM relation -> Talk:colour–magnitude relation
- Talk:CN band
- Talk:CN cycle -> Talk:carbon–nitrogen cycle
- Talk:CNO cycle -> Talk:carbon–nitrogen–oxygen cycle
- Talk:CN star
- Talk:Coalsack
- Talk:coaltitude
- Talk:COAST
- Talk:Coathanger
- Talk:COBE
- Talk:Cocoon Nebula
- Talk:cocoon star
- Talk:CoD -> Talk:Córdoba Durchmusterung
- Talk:coded mask
- Talk:coelostat
- Talk:coesite
- Talk:coherence
- Talk:coherence bandwidth
- Talk:colatitude
- Talk:cold camera
- Talk:cold dark matter
- Talk:collapsar
- Talk:colles
- Talk:collimation
- Talk:collimation error
- Talk:collimator
- Talk:Colombo Gap
- Talk:colorimetry -> Talk:colour index
- Talk:colour -> Talk:colour index
- Talk:colour excess
- Talk:colour index
- Talk:colour–luminosity relation -> Talk:colour–magnitude relation
- Talk:colour–magnitude relation
- Talk:colour temperature
- Talk:Columba
- Talk:column density
- Talk:colure
- Talk:cometary coma
- Talk:optical coma
- Talk:Coma Berenices
- Talk:Coma Cluster
- Talk:Coma Star Cluster
- Talk:Coma–Virgo Cluster -> Talk:Virgo Cluster
- Talk:Combined Array for Research in Millimeter-wave Astronomy
- Talk:combined magnitude
- Talk:comes
- Talk:comet
- Talk:cometary globule
- Talk:comet family
- Talk:comet-seeker
- Talk:commensurability
- Talk:Andrew Ainslie Common
- Talk:common envelope binary
- Talk:common proper motion
- Talk:compact galaxy
- Talk:compact object
- Talk:compact source
- Talk:comparator
- Talk:comparison spectrum
- Talk:composite-spectrum binary
- Talk:Compton effect
- Talk:Compton Gamma Ray Observatory
- Talk:Compton–Getting effect
- Talk:Compton scattering -> Talk:Compton effect
- Talk:Compton upscattering -> Talk:inverse Compton scattering
- Talk:Concordia family
- Talk:Cone Nebula
- Talk:confusion
- Talk:conic section
- Talk:conjunction
- Talk:constant of aberration -> Talk:annual aberration
- Talk:constellation
- Talk:constructive interference -> Talk:interference
- Talk:contact binary
- Talk:continuous creation
- Talk:continuous spectrum
- Talk:continuum
- Talk:stellar convection
- Talk:convective envelope
- Talk:convective equilibrium
- Talk:convective overshoot -> Talk:overshooting
- Talk:convective zone
- Talk:convergent point
- Talk:converging lens
- Talk:convolution
- Talk:Thomas Cooke
- Talk:cooled camera -> Talk:cold camera
- Talk:cooling flow
- Talk:coorbital
- Talk:Coordinated Universal Time
- Talk:coordinate systems -> Talk:celestial coordinates
- Talk:coordinate time
- Talk:Copernican system
- Talk:Nicolaus Copernicus
- Talk:Copernicus satellite
- Talk:Coprates
- Talk:Cor Caroli
- Talk:Cordelia
- Talk:Córdoba Durchmusterung
- Talk:planetary core
- Talk:stellar core
- Talk:core collapse
- Talk:1
- Talk:2
- Talk:Coriolis force
- Talk:corona
- Talk:1
- Talk:2
- Talk:3
- Talk:Corona Australis
- Talk:Corona Borealis
- Talk:coronagraph
- Talk:coronal bright point
- Talk:coronal condensation
- Talk:coronal hole
- Talk:coronal lines
- Talk:coronal loop
- Talk:coronal mass ejection
- Talk:coronal plume
- Talk:coronal rain
- Talk:COROT
- Talk:co-rotation
- Talk:corpuscular radiation
- Talk:1
- Talk:2
- Talk:corrector plate
- Talk:correlation detection
- Talk:correlation function
- Talk:correlation receiver
- Talk:correlator
- Talk:Corvus
- Talk:COS-B
- Talk:cosmic abundance
- Talk:Cosmic Background Explorer
- Talk:cosmic background radiation -> Talk:cosmic microwave background
- Talk:CBR -> Talk:cosmic background radiation
- Talk:cosmic censorship
- Talk:cosmic dust
- Talk:cosmic microwave background
- Talk:cosmic rays
- Talk:cosmic-ray shower
- Talk:cosmic scale factor
- Talk:cosmic string
- Talk:cosmic texture
- Talk:cosmic year
- Talk:cosmochemistry -> Talk:astrochemistry
- Talk:cosmological constant
- Talk:cosmological distance scale
- Talk:cosmological principle
- Talk:cosmology
- Talk:cosmos
- Talk:Cosmos satellites
- Talk:COSPAR
- Talk:coudé focus
- Talk:Couder telescope
- Talk:counterglow -> Talk:gegenschein
- Talk:Philip Herbert Cowell
- Talk:c.p.m. -> Talk:common proper motion
- Talk:Crab Nebula
- Talk:Crab Pulsar
- Talk:Crater
- Talk:crater
- Talk:crater chain
- Talk:crater counting
- Talk:crêpe ring
- Talk:crepuscular rays
- Talk:crescent
- Talk:Cressida
- Talk:Crimean Astrophysical Observatory
- Talk:critical density
- Talk:Andrew Claude de la Cherois Crommelin
- Talk:cross-axis mounting
- Talk:crossing time
- Talk:cross-wire micrometer
- Talk:crown glass
- Talk:crust
- Talk:Crux
- Talk:cryostat
- Talk:cryovolcanism
- Talk:C star
- Talk:CTIO -> Talk:Cerro Tololo Inter-American Observatory
- Talk:Cubewano
- Talk:culmination
- Talk:curvature of field
- Talk:curvature of space -> Talk:curvature of spacetime
- Talk:curvature of spacetime
- Talk:curvature radiation
- Talk:curve of growth
- Talk:cusp
- Talk:cusp gap
- Talk:Cybele group
- Talk:cyclotron maser
- Talk:cyclotron radiation
- Talk:Cygnus
- Talk:Cygnus A
- Talk:Cygnus Loop
- Talk:Cygnus Rift
- Talk:Cygnus X-1
- Talk:Cynthian
- Talk:Cytherean
D2
edit- Talk:Dactyl
- Talk:Dall–Kirkham telescope
- Talk:Damocles
- Talk:Damocloid
- Talk:André Danjon
- Talk:Danjon astrolabe
- Talk:Danjon scale
- Talk:dark adaptation
- Talk:dark energy
- Talk:dark galaxy
- Talk:dark matter
- Talk:dark nebula
- Talk:daughter isotope
- Talk:Davida
- Talk:David Dunlap Observatory
- Talk:Raymond Davis, Jr
- Talk:William Rutter Dawes
- Talk:Dawes limit
- Talk:Dawn
- Talk:day
- Talk:Daylight Saving Time -> Talk:Summer Time
- Talk:day number
- Talk:1
- Talk:2
- Talk:D-class asteroid
- Talk:DCT -> Talk:Discovery Channel Telescope
- Talk:DDO classification
- Talk:DDO photometry
- Talk:dec. -> Talk:declination
- Talk:deceleration parameter
- Talk:Comet de Chéseaux (C/1743 X1)
- Talk:declination
- Talk:declination axis
- Talk:deconvolution
- Talk:decoupling
- Talk:dedispersion
- Talk:Deep Impact
- Talk:deep-sky object
- Talk:Deep Space Network
- Talk:Deep Space 1
- Talk:defect of illumination
- Talk:deferent
- Talk:deflection of light
- Talk:degeneracy
- Talk:degenerate star
- Talk:degree of arc
- Talk:degrees of freedom
- Talk:Deimos
- Talk:delay line
- Talk:Delphinus
- Talk:δ -> Talk:declination
- Talk:delta -> Talk:declination
- Talk:Delta Aquarid meteors
- Talk:Delta Cepheid star -> Talk:classical Cepheid
- Talk:Delta Delphini star
- Talk:Delta Scuti star
- Talk:delta T
- Talk:ΔT
- Talk:Demon Star
- Talk:Deneb
- Talk:Deneb Kaitos
- Talk:Denebola
- Talk:William Frederick Denning
- Talk:density parameter
- Talk:density wave
- Talk:descending node
- Talk:Desdemona
- Talk:Willem de Sitter
- Talk:de Sitter universe
- Talk:Despina
- Talk:destructive interference -> Talk:interference
- Talk:detached binary
- Talk:deuterium
- Talk:Gérard Henri de Vaucouleurs
- Talk:dewar
- Talk:dew cap
- Talk:D galaxy
- Talk:diagonal
- Talk:diamond ring
- Talk:Diana Chasma
- Talk:dichotomy
- Talk:dichroic mirror
- Talk:Robert Henry Dicke
- Talk:Dicke radiometer
- Talk:Dicke switch
- Talk:dielectronic recombination
- Talk:differential rotation
- Talk:differentiation
- Talk:diffraction
- Talk:diffraction grating
- Talk:diffraction-limited
- Talk:diffraction pattern
- Talk:diffraction rings
- Talk:diffuse interstellar bands
- Talk:diffuse nebula
- Talk:diogenite
- Talk:Dione
- Talk:dioptric system
- Talk:Diphda -> Talk:Deneb Kaitos
- Talk:dipole
- Talk:1
- Talk:2
- Talk:3
- Talk:dipole antenna
- Talk:Dirac cosmology
- Talk:directivity
- Talk:direct motion
- Talk:dirty snowball
- Talk:disconnection event
- Talk:Discovery Channel Telescope
- Talk:Discovery Program
- Talk:dish antennae
- Talk:disk galaxy
- Talk:disk population
- Talk:disparition brusque -> Talk:filament
- Talk:dispersion
- Talk:1
- Talk:2
- Talk:dispersion measure
- Talk:distance modulus
- Talk:distortion
- Talk:diurnal
- Talk:diurnal aberration
- Talk:diurnal inequality
- Talk:diurnal libration
- Talk:diurnal motion
- Talk:diurnal parallax
- Talk:diverging lens
- Talk:D layer
- Talk:D lines
- Talk:dMe star
- Talk:Dobsonian telescope
- Talk:Dog Star
- Talk:John Dollond
- Talk:domain wall
- Talk:dome
- Talk:Dominion Astrophysical Observatory
- Talk:Dominion Radio Astrophysical Observatory
- Talk:Comet Donati (C/1858 L1)
- Talk:Christian Johann Doppler
- Talk:Doppler broadening
- Talk:Doppler effect -> Talk:Doppler shift
- Talk:dopplergram
- Talk:Doppler shift
- Talk:Dorado
- Talk:dorsum
- Talk:Double Cluster
- Talk:Double Double
- Talk:double-lined binary
- Talk:double-mode variable
- Talk:double pulsar
- Talk:double quasar
- Talk:double star
- Talk:doublet
- Talk:1
- Talk:2
- Talk:DQ Herculis star
- Talk:Draco
- Talk:draconic month
- Talk:Draconid meteors -> Talk:Giacobinid meteors
- Talk:Drake equation
- Talk:Henry Draper
- Talk:Draper
- Talk:drawtube
- Talk:Johan Ludvig Emil Dreyer
- Talk:drifting sub-pulse
- Talk:drift scan
- Talk:drive
- Talk:D star
- Talk:Dubhe
- Talk:Dumbbell Nebula
- Talk:dust
- Talk:dust tail -> Talk:cometary tail
- Talk:duty cycle
- Talk:dwarf Cepheid
- Talk:dwarf galaxy
- Talk:dwarf nova
- Talk:dwarf planet
- Talk:dwarf spheroidal galaxy
- Talk:dwarf star
- Talk:dwarf variable
- Talk:Dwingeloo galaxy
- Talk:Dwingeloo Radio Observatory
- Talk:dynamical equinox
- Talk:dynamical friction
- Talk:dynamical parallax
- Talk:dynamical time
- Talk:dynamo
- Talk:Frank Watson Dyson
E2
edit- Talk:Eagle Nebula
- Talk:early-type galaxy
- Talk:early-type star
- Talk:Earth
- Talk:Earth coorbital asteroid -> Talk:Apollo group -> Talk:Aten group
- Talk:Earth-crossing asteroid -> Talk:Amor group
- Talk:Earth-approaching asteroid
- Talk:earthlight -> Talk:earthshine
- Talk:eccentric anomaly
- Talk:eccentricity
- Talk:echelle grating
- Talk:echelle spectrograph
- Talk:E-class asteroid
- Talk:eclipse
- Talk:eclipse season
- Talk:eclipse year
- Talk:eclipsing binary
- Talk:ecliptic
- Talk:ecliptic coordinates
- Talk:ecliptic latitude
- Talk:ecliptic limits
- Talk:ecliptic longitude
- Talk:ecliptic pole
- Talk:E corona
- Talk:Arthur Stanley Eddington
- Talk:Eddington limit
- Talk:Edgeworth–Kuiper Belt -> Talk:Kuiper Belt
- Talk:E-ELT -> Talk:European Extremely Large Telescope
- Talk:effective aperture
- Talk:effective area
- Talk:effective focal length
- Talk:effective temperature
- Talk:Effelsberg Radio Observatory
- Talk:Egg Nebula
- Talk:Albert Einstein
- Talk:Einstein coefficient
- Talk:Einstein Cross
- Talk:Einstein–de Sitter universe
- Talk:Einstein Observatory
- Talk:Einstein ring
- Talk:Einstein shift -> Talk:gravitational redshift
- Talk:ejecta
- Talk:Elara
- Talk:E layer
- Talk:electromagnetic radiation
- Talk:electromagnetic spectrum
- Talk:electron
- Talk:electron degeneracy
- Talk:electron density
- Talk:electron scattering opacity
- Talk:electron temperature
- Talk:electronvolt
- Talk:chemical element
- Talk:optical element
- Talk:elementary particle
- Talk:abundance of elements
- Talk:orbital elements
- Talk:E line
- Talk:Ellerman bomb
- Talk:ellipse
- Talk:ellipsoid
- Talk:ellipsoidal variable
- Talk:elliptic aberration -> Talk:E-terms
- Talk:elliptical galaxy
- Talk:ellipticity -> Talk:oblateness
- Talk:Elnath -> Talk:Alnath
- Talk:elongation
- Talk:1
- Talk:2
- Talk:Eltanin -> Talk:Etamin
- Talk:Elysium Planitia
- Talk:emersion
- Talk:emission
- Talk:emission line
- Talk:emission nebula
- Talk:emission spectrum
- Talk:emissivity
- Talk:photographic emulsion
- Talk:Enceladus
- Talk:Comet 2P/Encke
- Talk:Johann Franz Encke
- Talk:Encke Division
- Talk:energy level
- Talk:English mounting
- Talk:Enif
- Talk:Ensisheim meteorite
- Talk:enstatite chondrite
- Talk:entrainment
- Talk:entropy
- Talk:envelope (astronomy)
- Talk:eon -> Talk:aeon
- Talk:Eos family
- Talk:epact
- Talk:Ep galaxy
- Talk:ephemeris
- Talk:Ephemeris Time
- Talk:epicycle
- Talk:Epimetheus
- Talk:epoch
- Talk:e-process
- Talk:Epsilon Aurigae
- Talk:equant
- Talk:equation (astronomy)
- Talk:equation of light
- Talk:equation of the centre
- Talk:equation of the equinoxes
- Talk:equation of the origins
- Talk:equation of time
- Talk:equator
- Talk:equatorial bulge
- Talk:equatorial coordinates
- Talk:equatorial horizontal parallax
- Talk:equatorial mounting
- Talk:equinoctial colure
- Talk:equinox
- Talk:equipotential surface
- Talk:equivalence principle
- Talk:equivalent focal length
- Talk:equivalent width
- Talk:Equuleus
- Talk:ERA -> Talk:Earth rotation angle
- Talk:Eratosthenes
- Talk:Erfle eyepiece
- Talk:ergosphere
- Talk:Eridanus
- Talk:Eris
- Talk:Eros
- Talk:eruptive binary
- Talk:eruptive prominence
- Talk:eruptive variable
- Talk:ESA -> Talk:European Space Agency
- Talk:escape velocity
- Talk:Eskimo Nebula
- Talk:ESO -> Talk:European Southern Observatory
- Talk:ET -> Talk:Ephemeris Time
- Talk:Eta Aquarid meteors
- Talk:Eta Carinae
- Talk:Eta Carinae Nebula
- Talk:etalon
- Talk:Etamin
- Talk:E-terms
- Talk:ether
- Talk:eucrite
- Talk:Eudoxus of Cnidus
- Talk:Leonhard Euler
- Talk:Eunomia family
- Talk:Europa
- Talk:European Extremely Large Telescope
- Talk:European Southern Observatory
- Talk:European Space Agency
- Talk:European VLBI Network
- Talk:EUV -> Talk:extreme ultraviolet
- Talk:EUVE -> Talk:Extreme Ultraviolet Explorer
- Talk:eV -> Talk:electronvolt
- Talk:evection
- Talk:evening star
- Talk:event horizon
- Talk:Evershed effect
- Talk:EVN -> Talk:European VLBI Network
- Talk:evolved star
- Talk:excitation
- Talk:excitation temperature
- Talk:exit cone
- Talk:exit pupil
- Talk:EX Lupi star
- Talk:exobiology -> Talk:astrobiology
- Talk:ExoMars
- Talk:exoplanet -> Talk:extrasolar planet
- Talk:EXor -> Talk:EX Lupi star
- Talk:Exosat
- Talk:exosphere
- Talk:expanding universe
- Talk:Explorer
- Talk:exposure age
- Talk:extended source
- Talk:1
- Talk:2
- Talk:atmospheric extinction
- Talk:interstellar extinction
- Talk:extragalactic nebula -> Talk:galaxy
- Talk:extrasolar planet
- Talk:extreme Population I star
- Talk:extreme ultraviolet
- Talk:Extreme Ultraviolet Explorer
- Talk:extrinsic variable
- Talk:eye lens
- Talk:eyepiece
- Talk:eye relief
F2
edit- Talk:Faber–Jackson relation
- Talk:David Fabricius
- Talk:Johann Fabricius
- Talk:Johannes Fabricius
- Talk:Fabry lens
- Talk:Fabry–Perot interferometer
- Talk:facula
- Talk:1
- Talk:2
- Talk:fall
- Talk:falling star -> Talk:meteor
- Talk:False Cross
- Talk:Fanaroff–Riley class
- Talk:fan beam
- Talk:Faraday effect
- Talk:far infrared
- Talk:farrum
- Talk:far ultraviolet
- Talk:Far Ultraviolet Spectroscopic Explorer
- Talk:Fast Auroral Snapshot Explorer
- Talk:fast nova
- Talk:Faulkes Telescopes
- Talk:fault
- Talk:F band
- Talk:F-class asteroid
- Talk:F corona
- Talk:feed
- Talk:fermion
- Talk:fibrille
- Talk:field curvature -> Talk:curvature of field
- Talk:field equations
- Talk:field flattener
- Talk:field lens
- Talk:field of view
- Talk:field star
- Talk:field stop
- Talk:53 Persei star
- Talk:figure
- Talk:filament
- Talk:1
- Talk:2
- Talk:filamentary nebula
- Talk:filar micrometer
- Talk:filigree
- Talk:filled aperture
- Talk:filled-centre supernova remnant -> Talk:plerion
- Talk:filter
- Talk:1
- Talk:2
- Talk:filtergram
- Talk:find
- Talk:finder
- Talk:fine structure
- Talk:fireball
- Talk:first contact
- Talk:first point of Aries
- Talk:first point of Libra
- Talk:first quarter
- Talk:Fish Mouth
- Talk:fission
- Talk:fission track
- Talk:Fitzgerald contraction -> Talk:Lorentz–Fitzgerald contraction
- Talk:fixed stars
- Talk:FK
- Talk:FK Comae Berenices star
- Talk:John Flamsteed
- Talk:Flamsteed numbers
- Talk:solar flare
- Talk:flare star
- Talk:flash spectrum
- Talk:flash star
- Talk:flat
- Talk:polar flattening
- Talk:F layer
- Talk:Williamina Paton Fleming
- Talk:flexus
- Talk:flickering
- Talk:flint glass
- Talk:flocculi
- Talk:1 -> Talk:mottles
- Talk:2 -> Talk:plages
- Talk:Flora group
- Talk:fluctus
- Talk:flumen
- Talk:fluorescence
- Talk:fluorite
- Talk:flux
- Talk:flux collector
- Talk:flux density
- Talk:1
- Talk:2
- Talk:flux tube
- Talk:flux unit
- Talk:f/number
- Talk:focal distance
- Talk:focal length
- Talk:focal plane
- Talk:focal point
- Talk:focal ratio
- Talk:focal reducer
- Talk:focal surface
- Talk:optical focus
- Talk:orbital focus
- Talk:Fokker–Planck equation
- Talk:folded dipole
- Talk:following
- Talk:Fomalhaut
- Talk:footpoint -> Talk:coronal loop
- Talk:forbidden line
- Talk:Forbush effect
- Talk:fork mounting
- Talk:Fornax
- Talk:Fornax A
- Talk:Fornax Dwarf Galaxy
- Talk:47 Tucanae
- Talk:forward scattering
- Talk:fossa
- Talk:Foucault test
- Talk:four-colour photometry -> Talk:Strömgren photometry
- Talk:Fourier analysis
- Talk:Fourier transform
- Talk:Fourier transform spectrometer
- Talk:fourth contact
- Talk:William Alfred Fowler
- Talk:Fp star
- Talk:fractional method
- Talk:frame dragging
- Talk:frame of reference
- Talk:Franklin-Adams charts
- Talk:Joseph von Fraunhofer
- Talk:Fraunhofer lines
- Talk:Fred Lawrence Whipple Observatory
- Talk:free–bound transition
- Talk:free–free transition
- Talk:frequency
- Talk:frequency analysis -> Talk:Fourier analysis
- Talk:Friedmann universe
- Talk:fringe -> Talk:interference pattern
- Talk:fringe pattern
- Talk:f-spot
- Talk:F star
- Talk:FTS -> Talk:Fourier transform spectroscopy
- Talk:full Moon
- Talk:full-wave dipole
- Talk:full width at half maximum
- Talk:fundamental catalogue
- Talk:fundamental mode
- Talk:fundamental plane
- Talk:fundamental star
- Talk:fuor -> Talk:FU Orionis star
- Talk:FUSE -> Talk:Far Ultraviolet Spectroscopic Explorer
- Talk:fusion
- Talk:fusion crust
- Talk:future light cone -> Talk:light cone
- Talk:FWHM -> Talk:full width at half maximum
G2
edit- Talk:g -> Talk:acceleration of free fall
- Talk:G -> Talk:gravitational constant
- Talk:Gacrux -> Talk:Gamma Crucis
- Talk:Gaia
- Talk:gain
- Talk:galactic anticentre
- Talk:galactic bulge
- Talk:galactic centre
- Talk:galactic cluster
- Talk:galactic coordinates
- Talk:galactic disk
- Talk:galactic equator
- Talk:galactic halo
- Talk:galactic latitude
- Talk:galactic longitude
- Talk:galactic magnetic field
- Talk:galactic nucleus
- Talk:galactic plane
- Talk:galactic pole
- Talk:galactic rotation
- Talk:galactic window
- Talk:galactic year -> Talk:cosmic year
- Talk:Galatea
- Talk:Galaxy
- Talk:galaxy
- Talk:galaxy cannibalism
- Talk:galaxy cluster
- Talk:galaxy encounter
- Talk:galaxy evolution
- Talk:Galaxy Evolution Explorer
- Talk:galaxy formation
- Talk:galaxy merger
- Talk:GALEX -> Talk:Galaxy Evolution Explorer
- Talk:Galilean satellites
- Talk:Galilean telescope
- Talk:Galileo
- Talk:Galileo Galilei
- Talk:Galileo National Telescope
- Talk:Galileo Regio
- Talk:Johann Gottfried Galle
- Talk:Galle Ring
- Talk:Gamma Cassiopeiae star
- Talk:Gamma Crucis
- Talk:Gamma Doradus star
- Talk:gamma-ray astronomy
- Talk:gamma-ray background
- Talk:gamma-ray burst
- Talk:Gamma-ray Large Area Space Telescope
- Talk:gamma rays
- Talk:gamma-ray telescope
- Talk:George Gamow
- Talk:Ganymede
- Talk:Sergei Illarionovich Gaposchkin -> Talk:Cecilia Payne-Gaposchkin
- Talk:Garnet Star
- Talk:gas giant -> Talk:giant planet
- Talk:Gaspra
- Talk:gas scintillation proportional counter
- Talk:gas tail -> Talk:cometary tail
- Talk:Carl Friedrich Gauss
- Talk:Gaussian gravitational constant
- Talk:G band
- Talk:G-class asteroid
- Talk:GCRS -> Talk:Geocentric Celestial Reference System
- Talk:GCVS -> Talk:General Catalogue of Variable Stars
- Talk:gegenschein
- Talk:Geminga
- Talk:Gemini
- Talk:Geminid meteors
- Talk:Gemini Observatory
- Talk:Gemma -> Talk:Alphekka
- Talk:General Catalogue of Variable Stars
- Talk:general precession
- Talk:general theory of relativity
- Talk:Genesis
- Talk:Geneva photometry
- Talk:geo-
- Talk:geocentric
- Talk:Geocentric Celestial Reference System
- Talk:geocentric coordinates
- Talk:Geocentric Coordinate Time
- Talk:geocentric equatorial parallax
- Talk:geocentric parallax
- Talk:geocorona
- Talk:geodesic
- Talk:geodesy
- Talk:Geographos
- Talk:geoid
- Talk:geomagnetic storm
- Talk:geomagnetism
- Talk:geometrical albedo
- Talk:geometrical libration -> Talk:optical libration
- Talk:georgiaite
- Talk:geostationary orbit
- Talk:geosynchronous orbit
- Talk:geotail -> Talk:magnetotail
- Talk:germanium detector
- Talk:German mounting
- Talk:GHA
- Talk:ghost crater
- Talk:Ghost of Jupiter
- Talk:Riccardo Giacconi
- Talk:Giacobinid meteors
- Talk:Comet 21P/Giacobini–Zinner
- Talk:giant branch
- Talk:Giant Magellan Telescope
- Talk:Giant Metrewave Radio Telescope
- Talk:giant molecular cloud
- Talk:giant planet
- Talk:giant star
- Talk:gibbous
- Talk:Gienah
- Talk:David Gill
- Talk:Ginga
- Talk:Giotto
- Talk:GLAST -> Talk:Gamma-ray Large Area Space Telescope
- Talk:Glauke
- Talk:glitch
- Talk:Global Oscillation Network Group
- Talk:globular cluster
- Talk:globule
- Talk:GMAT -> Talk:Greenwich Mean Astronomical Time
- Talk:GMC -> Talk:giant molecular cloud
- Talk:GMST -> Talk:Greenwich Mean Sidereal Time
- Talk:GMT -> Talk:Greenwich Mean Time
- Talk:GMT -> Talk:Giant Magellan Telescope
- Talk:gnomon
- Talk:Goddard Space Flight Center
- Talk:Gödel universe
- Talk:Thomas Gold
- Talk:Goldstone
- Talk:GONG -> Talk:Global Oscillation Network Group
- Talk:John Goodricke
- Talk:GoTo telescope
- Talk:Benjamin Apthorp Gould
- Talk:Gould's Belt
- Talk:graben
- Talk:interplanetary grains
- Talk:interstellar grains
- Talk:Granat
- Talk:grand unified theory
- Talk:Gran Telescopio Canarias
- Talk:granulation
- Talk:graticule -> Talk:reticle
- Talk:grating -> Talk:diffraction grating
- Talk:grating spectrometer
- Talk:gravitation
- Talk:gravitational acceleration
- Talk:gravitational collapse
- Talk:gravitational constant
- Talk:gravitational deflection
- Talk:gravitational energy
- Talk:gravitational field
- Talk:gravitational force
- Talk:gravitational instability
- Talk:gravitational lens
- Talk:gravitational mass
- Talk:gravitational radiation
- Talk:gravitational wave
- Talk:graviton
- Talk:gravity assist
- Talk:gravity gradient
- Talk:Gravity Probe B
- Talk:grazing-incidence telescope
- Talk:grazing occultation
- Talk:GRB -> Talk:gamma-ray burst
- Talk:Great Attractor
- Talk:Great Bear -> Talk:Ursa Major
- Talk:great circle
- Talk:Great Dark Spot
- Talk:greatest brilliancy
- Talk:greatest elongation
- Talk:Great Observatories
- Talk:Great Red Spot
- Talk:Great Rift
- Talk:Great September Comet (C/1882 R1)
- Talk:Great Wall
- Talk:Green Bank
- Talk:Green Bank Telescope
- Talk:green flash
- Talk:greenhouse effect
- Talk:Greenwich hour angle
- Talk:Greenwich Mean Astronomical Time
- Talk:Greenwich Mean Sidereal Time
- Talk:Greenwich Mean Time
- Talk:Greenwich meridian
- Talk:Greenwich Observatory
- Talk:Greenwich sidereal date
- Talk:Greenwich Sidereal Time
- Talk:Gregorian calendar
- Talk:Gregorian telescope
- Talk:James Gregory
- Talk:Comet 26P/Grigg–Skjellerup
- Talk:grism
- Talk:grooved terrain
- Talk:Grotrian diagram
- Talk:ground state
- Talk:GRS -> Talk:Great Red Spot
- Talk:Howard Grubb
- Talk:Grus
- Talk:GST -> Talk:Greenwich Sidereal Time
- Talk:G star
- Talk:GTC -> Talk:Gran Telescopio Canarias
- Talk:Guardians
- Talk:guest star
- Talk:guider
- Talk:guide star
- Talk:guide telescope
- Talk:Gum Nebula
- Talk:GUT -> Talk:grand unified theory
- Talk:GW Virginis star -> Talk:ZZ Ceti star
- Talk:gyrofrequency
- Talk:gyrosynchrotron radiation
H2
edit- Talk:HA -> Talk:hour angle
- Talk:Hadar
- Talk:Hadley circulation
- Talk:Hadley Rille
- Talk:hadron
- Talk:hadron era
- Talk:HAEBE -> Talk:Herbig Ae/Be star
- Talk:Haedi -> Talk:Kids
- Talk:Haig mount -> Talk:Scotch mount
- Talk:Hakucho
- Talk:halation
- Talk:HALCA
- Talk:George Ellery Hale
- Talk:Comet Hale–Bopp (C/1995 01)
- Talk:Hale Observatories
- Talk:Hale's law -> Talk:bipolar group
- Talk:Hale telescope
- Talk:half-life
- Talk:half-wave dipole
- Talk:half-width -> Talk:full width at half maximum
- Talk:Asaph Hall
- Talk:Edmond Halley
- Talk:Halley-family comet
- Talk:Halley's Comet
- Talk:atmospheric halo
- Talk:galactic halo
- Talk:halo CME
- Talk:halo orbit
- Talk:halo population
- Talk:Hα
- Talk:Hamal
- Talk:H and K lines
- Talk:Hanle effect
- Talk:hard X-rays
- Talk:Haro galaxy
- Talk:Hartebeesthoek Radio Astronomy Observatory
- Talk:HartRAO -> Talk:Hartebeesthoek Radio Astronomy Observatory
- Talk:Hartmann test
- Talk:Haruka -> Talk:HALCA
- Talk:Harvard classification
- Talk:Harvard College Observatory
- Talk:Harvard Revised Photometry
- Talk:Harvard–Smithsonian Center for Astrophysics
- Talk:harvest Moon
- Talk:Hat Creek Radio Observatory
- Talk:Hathor
- Talk:Haute-Provence Observatory
- Talk:Stephen William Hawking
- Talk:Hawking radiation
- Talk:Hayabusa
- Talk:Hayashi track
- Talk:Haystack Observatory
- Talk:HCG -> Talk:Hickson compact group
- Talk:HD Catalogue -> Talk:Henry Draper Catalogue
- Talk:cometary head
- Talk:head–tail galaxy
- Talk:HEAO -> Talk:High Energy Astrophysical Observatory
- Talk:heat death of the Universe
- Talk:Heaviside layer -> Talk:E layer
- Talk:heavy element
- Talk:heavy-metal star
- Talk:Hebe
- Talk:Hektor
- Talk:Helene
- Talk:heli- -> Talk:Sun
- Talk:helio- -> Talk:Sun
- Talk:heliacal rising and setting
- Talk:heliocentric
- Talk:1
- Talk:2
- Talk:heliocentric coordinates
- Talk:heliocentric latitude
- Talk:heliocentric longitude
- Talk:heliocentric parallax -> Talk:annular parallax
- Talk:heliographic coordinates
- Talk:heliometer
- Talk:heliopause
- Talk:helioseismology
- Talk:heliosheath
- Talk:heliosphere
- Talk:Helios probes
- Talk:heliostat
- Talk:helium burning
- Talk:helium flash
- Talk:helium shell flash
- Talk:helium star
- Talk:Helix Nebula
- Talk:Hellas Planitia
- Talk:helmet streamer -> Talk:streamer
- Talk:Helmholtz–Kelvin contraction
- Talk:hemispherical albedo
- Talk:Henry Draper Catalogue
- Talk:Henyey track
- Talk:Hephaistos
- Talk:Heraclides of Pontus
- Talk:Herbig Ae/Be star
- Talk:Herbig–Haro object
- Talk:Hercules
- Talk:Hercules Cluster
- Talk:Hercules X-1
- Talk:Herculina
- Talk:Hermes
- Talk:Caroline Lucretia Herschel
- Talk:Karoline Lucretia Herschel -> Talk:Caroline Lucretia Herschel
- Talk:John Frederick William Herschel
- Talk:Frederick William Herschel -> Talk:William Herschel
- Talk:Friedrich Wilhelm Herschel -> Talk:William Herschel
- Talk:William Herschel
- Talk:Herschelian telescope
- Talk:Comet 35P/Herschel–Rigollet
- Talk:Herschel Space Observatory
- Talk:Hertha family -> Talk:Nysa family
- Talk:hertz
- Talk:Ejnar Hertzsprung
- Talk:Hertzsprung gap
- Talk:Hertzsprung–Russell diagram
- Talk:Victor Francis Hess
- Talk:HESSI -> Talk:Ramaty High-energy Solar Spectroscopic Imager
- Talk:HETE-2 -> Talk:High Energy Transient Explorer-2
- Talk:Johannes Hevelius
- Talk:Antony Hewish
- Talk:hexahedrite
- Talk:HH object -> Talk:Herbig–Haro object
- Talk:Hickson compact group
- Talk:Hidalgo
- Talk:hierarchical cosmology
- Talk:High Energy Astrophysical Observatory
- Talk:high-energy astrophysics
- Talk:High-Energy Transient Explorer-2
- Talk:lunar highlands
- Talk:high-speed photometry
- Talk:high-velocity cloud
- Talk:high-velocity star
- Talk:Hilda group
- Talk:George William Hill
- Talk:Himalia
- Talk:Hind's Crimson Star
- Talk:Hind's Variable Nebula
- Talk:Hinode
- Talk:Hinotori
- Talk:Hipparchus of Nicaea
- Talk:Hipparcos
- Talk:Hirayama family
- Talk:Hiten
- Talk:H line -> Talk:H and K lines
- Talk:H magnitude
- Talk:Hoba West meteorite
- Talk:Hobby–Eberly Telescope
- Talk:Hohmann orbit
- Talk:Holmberg radius
- Talk:homogeneity
- Talk:homology
- Talk:Homunculus Nebula
- Talk:H I region
- Talk:Hooker Telescope
- Talk:horizon
- Talk:horizontal branch
- Talk:horizontal coordinates
- Talk:horizontal parallax
- Talk:horizontal refraction
- Talk:horn antenna
- Talk:Horologium
- Talk:Jeremiah Horrocks
- Talk:Jeremiah Horrox -> Talk:Jeremiah Horrocks
- Talk:Horsehead Nebula
- Talk:horseshoe mounting
- Talk:Horseshoe Nebula
- Talk:horseshoe orbit
- Talk:horst
- Talk:hot Big Bang
- Talk:hot dark matter
- Talk:hot Jupiter
- Talk:hot spot
- Talk:1
- Talk:2
- Talk:hour angle
- Talk:hour circle
- Talk:Hourglass Nebula
- Talk:howardite
- Talk:Fred Hoyle
- Talk:HPBW -> Talk:half-power beamwidth
- Talk:half-power beamwidth -> Talk:beamwidth
- Talk:HR diagram -> Talk:Hertzsprung–Russell diagram
- Talk:HR number
- Talk:HSO -> Talk:Herschel Space Observatory
- Talk:HST -> Talk:Hubble Space Telescope
- Talk:H20 maser
- Talk:H II region
- Talk:Edwin Powell Hubble
- Talk:Hubble classification
- Talk:Hubble constant
- Talk:Hubble diagram
- Talk:Hubble flow
- Talk:Hubble law
- Talk:Hubble parameter -> Talk:Hubble constant
- Talk:Hubble radius
- Talk:Hubble–Sandage variable
- Talk:Hubble Space Telescope
- Talk:Hubble's Variable Nebula
- Talk:Hubble time
- Talk:William Huggins
- Talk:Hendrik ('Henk') Christoffel van de Hulst
- Talk:Milton Lasell Humason
- Talk:hummocky terrain
- Talk:Humphreys series
- Talk:Hungaria group
- Talk:hunter's Moon
- Talk:Huygenian eyepiece
- Talk:Christiaan Huygens
- Talk:Huygens Gap
- Talk:Huygens probe
- Talk:Hyades
- Talk:Comet Hyakutake (C/1996 B2)
- Talk:Hydra
- Talk:hydrocarbon
- Talk:hydrogen
- Talk:hydrogen burning
- Talk:hydrogen emission region
- Talk:hydrogen ion
- Talk:hydrogen line -> Talk:21-centimetre line
- Talk:hydrogen spectrum
- Talk:hydrostatic equilibrium
- Talk:hydroxyl
- Talk:Hydrus
- Talk:Hygiea
- Talk:hyperbola
- Talk:hyperbolic comet
- Talk:hyperbolic orbit
- Talk:hyperbolic velocity
- Talk:hyperboloid
- Talk:hyperfine structure
- Talk:hypergiant star
- Talk:Hyperion
- Talk:hypernova
- Talk:hyperon
- Talk:hypersensitization
- Talk:hypersthene achondrite -> Talk:diogenite
- Talk:hypervelocity impact
- Talk:Hz -> Talk:hertz
- Talk:HZ43
I2
edit- Talk:Iapetus
- Talk:IAU -> Talk:International Astronomical Union
- Talk:IC -> Talk:Index Catalogue
- Talk:Icarus
- Talk:ICE -> Talk:International Cometary Explorer
- Talk:ICRF -> Talk:International Celestial Reference Frame
- Talk:ICRS -> Talk:International Celestial Reference System
- Talk:Ida
- Talk:IGM -> Talk:intergalactic medium
- Talk:igneous
- Talk:IGY -> Talk:International Geophysical Year
- Talk:Comet Ikeya–Seki (C/1965 S1)
- Talk:Comet Ikeya–Zhang (153P/)
- Talk:illuminance
- Talk:IMAGE -> Talk:Imager for Magnetopause-to-Aurora Global Exploration
- Talk:image intensifier -> Talk:image tube
- Talk:Image Photon Counting System
- Talk:Imager for Magnetopause-to-Aurora Global Exploration
- Talk:image tube
- Talk:imaging photometer -> Talk:area photometer
- Talk:I magnitude
- Talk:Imbrium Basin
- Talk:immersion
- Talk:impact crater
- Talk:impactite
- Talk:impersonal astrolabe -> Talk:Danjon astrolabe
- Talk:inclination
- Talk:1
- Talk:2
- Talk:Index Catalogue
- Talk:indochinite
- Talk:Indus
- Talk:inequality
- Talk:inert gas -> Talk:noble gas
- Talk:inertial coordinate system
- Talk:inertial mass
- Talk:inertial reference frame
- Talk:infall velocity
- Talk:inferior conjunction
- Talk:inferior planet
- Talk:inflationary universe
- Talk:Infrared Astronomical Satellite
- Talk:infrared astronomy
- Talk:infrared cirrus
- Talk:infrared excess
- Talk:infrared photometry
- Talk:infrared radiation
- Talk:infrared source
- Talk:Infrared Space Observatory
- Talk:infrared telescope
- Talk:infrared window
- Talk:initial mass function
- Talk:Robert Thorburn Ayton Innes
- Talk:Innisfree meteorite
- Talk:insolation
- Talk:instability strip
- Talk:Institut de Radio Astronomie Millimétrique
- Talk:INT -> Talk:Isaac Newton Telescope
- Talk:INTEGRAL -> Talk:International Gamma-Ray Astrophysics Laboratory
- Talk:integrated magnitude
- Talk:integration time
- Talk:intensity
- Talk:intensity interferometer
- Talk:interacting binary
- Talk:interacting galaxy
- Talk:Interamnia
- Talk:interference
- Talk:1
- Talk:2
- Talk:interference filter
- Talk:interference pattern
- Talk:interferometer
- Talk:intergalactic absorption
- Talk:intergalactic magnetic field
- Talk:intergalactic medium
- Talk:intermediate-band photometry
- Talk:intermediate-population star
- Talk:intermediate-type star
- Talk:International Astronomical Union
- Talk:International Atomic Time
- Talk:International Celestial Reference Frame
- Talk:International Celestial Reference System
- Talk:International Cometary Explorer
- Talk:International Date Line
- Talk:International Gamma-Ray Astrophysics Laboratory
- Talk:International Geophysical Year
- Talk:International Sun–Earth Explorer
- Talk:International Sunspot Number
- Talk:International Ultraviolet Explorer
- Talk:International Years of the Quiet Sun
- Talk:interplanetary matter
- Talk:interplanetary scintillation
- Talk:interpulse
- Talk:interstellar absorption
- Talk:interstellar maser
- Talk:interstellar matter
- Talk:interstellar molecule
- Talk:interstellar reddening -> Talk:interstellar absorption
- Talk:interstellar scintillation
- Talk:interstellar wind
- Talk:intrinsic colour index
- Talk:intrinsic variable
- Talk:invariable plane
- Talk:inverse Compton effect
- Talk:inverse Compton scattering -> Talk:inverse Compton effect
- Talk:inverse P Cygni profile -> Talk:P Cygni profile
- Talk:inverse-square law
- Talk:inversion layer -> Talk:atmospheric transparency
- Talk:Io (moon)
- Talk:iodine cell
- Talk:ion
- Talk:ionization
- Talk:ionization equilibrium
- Talk:ionization front
- Talk:ionization potential
- Talk:ionization temperature
- Talk:ionopause
- Talk:ionosphere
- Talk:ionospheric scintillation
- Talk:ion tail -> Talk:cometary tail
- Talk:Iota Aquarid meteors
- Talk:IPCS -> Talk:Image Photon Counting System
- Talk:IQSY -> Talk:International Years of the Quiet Sun
- Talk:IR -> Talk:infrared
- Talk:IRAM -> Talk:Institut de Radio Astronomie Millimétrique
- Talk:IRAS -> Talk:Infrared Astronomical Satellite
- Talk:Comet IRAS–Araki–Alcock (C/1983 H1)
- Talk:Iris (asteroid)
- Talk:iron meteorite
- Talk:iron peak
- Talk:irradiance
- Talk:irradiation
- Talk:1
- Talk:2
- Talk:irregular galaxy
- Talk:irregular variable
- Talk:IRTF -> Talk:NASA Infrared Telescope Facility
- Talk:Isaac Newton Group
- Talk:Isaac Newton Telescope
- Talk:ISEE -> Talk:International Sun–Earth Explorer
- Talk:Ishtar Terra
- Talk:ISM -> Talk:interstellar matter -> Talk:interstellar medium
- Talk:ISO (observatory) -> Talk:Infrared Space Observatory
- Talk:isochron
- Talk:isochrone
- Talk:isophotal wavelength
- Talk:isophote
- Talk:isotherm
- Talk:isothermal process
- Talk:isothermal region
- Talk:isotope
- Talk:isotropy
- Talk:IUE -> Talk:International Ultraviolet Explorer
- Talk:Izar
J2
edit- Talk:James Clerk Maxwell Telescope
- Talk:James Webb Space Telescope
- Talk:jansky
- Talk:Karl Guthe Jansky
- Talk:(Pierre) Jules César Janssen
- Talk:Janus (moon)
- Talk:JCMT -> Talk:James Clerk Maxwell Telescope
- Talk:JD -> Talk:Julian Date
- Talk:James Hopwood Jeans
- Talk:Jeans length
- Talk:Jeans mass
- Talk:jet (astronomical objects)
- Talk:Jet Propulsion Laboratory
- Talk:Jewel Box
- Talk:Jilin meteorite
- Talk:J magnitude
- Talk:Job's Coffin
- Talk:Jodrell Bank Observatory
- Talk:Johnson photometry
- Talk:Johnson Space Center
- Talk:Joint Astronomy Centre
- Talk:Harold Spencer Jones
- Talk:joule
- Talk:Jovian planet
- Talk:JPL -> Talk:Jet Propulsion Laboratory
- Talk:Julian calendar
- Talk:Julian Date
- Talk:Julian day number
- Talk:Julian epoch
- Talk:Juliet (moon)
- Talk:Juno (asteroid)
- Talk:Jupiter (planet)
- Talk:Jupiter–family comet
- Talk:JWST -> Talk:James Webb Space Telescope
K2
edit- Talk:K -> Talk:kelvin scale
- Talk:Immanuel Kant
- Talk:Kappa Crucis Cluster -> Talk:Jewel Box cluster
- Talk:Kappa Cygnid meteors
- Talk:kappa mechanism
- Talk:Jacobus Cornelius Kapteyn
- Talk:Kapteyn Selected Areas
- Talk:Kapteyn's Star
- Talk:Kaus Australis
- Talk:K corona
- Talk:K-correction
- Talk:Keck Telescopes
- Talk:Keeler Gap
- Talk:Kellner eyepiece
- Talk:Lord (William Thomson) Kelvin
- Talk:Kelvin–Helmholtz contraction -> Talk:Helmholtz–Kelvin contraction
- Talk:kelvin scale
- Talk:Kennedy Space Center
- Talk:Kepler (satellite)
- Talk:Johannes Kepler
- Talk:Johann Kepler -> Talk:Johannes Kepler
- Talk:Keplerian telescope
- Talk:Kepler's equation
- Talk:Kepler's laws
- Talk:Kepler's Star
- Talk:Kerr black hole
- Talk:Keyhole Nebula
- Talk:Keystone
- Talk:Kids (asterism)
- Talk:kinematic parallax
- Talk:kinetic energy
- Talk:kinetic temperature
- Talk:Gustav Robert Kirchhoff
- Talk:Kirchhoff's laws
- Talk:Kirin meteorite -> Talk:Jilin meteorite
- Talk:Daniel Kirkwood
- Talk:Kirkwood gaps
- Talk:Kitt Peak National Observatory
- Talk:Kleinmann–Low Nebula
- Talk:KL Nebula -> Talk:Kleinmann–Low Nebula
- Talk:K line -> Talk:H and K lines
- Talk:K magnitude
- Talk:knife-edge test -> Talk:Foucault test
- Talk:Kochab
- Talk:Comet Kohoutek (C/1973 E1)
- Talk:König eyepiece -> Talk:Erfle eyepiece
- Talk:Koronis family
- Talk:KPNO -> Talk:Kitt Peak National Observatory
- Talk:Kracht group
- Talk:Kramers opacity
- Talk:KREEP
- Talk:Kreutz sungrazer
- Talk:Kron–Cousins RI photometry
- Talk:Kruskal diagram
- Talk:K star
- Talk:Kueyen
- Talk:Gerard Peter Kuiper
- Talk:Kuiper Airborne Observatory
- Talk:Kuiper Belt
L2
edit- Talk:labes
- Talk:labyrinthus
- Talk:Nicolas Louis de Lacaille
- Talk:Lacerta
- Talk:Lacertid -> Talk:BL Lacertae object
- Talk:lacus
- Talk:Lagoon Nebula
- Talk:Joseph Louis de Lagrange(-Tournier)
- Talk:Lagrangian point
- Talk:l'Aigle meteorite shower
- Talk:Joseph Jérôme (Le Français) de Lalande
- Talk:Lalande 21185
- Talk:Lambda Boötis star
- Talk:Lambda Eridani star
- Talk:La Palma -> Talk:Roque de los Muchachos Observatory
- Talk:Pierre Simon de Laplace
- Talk:Laplacian plane
- Talk:Large Binocular Telescope
- Talk:Large Magellanic Cloud
- Talk:Large Millimeter Telescope
- Talk:large-scale structure
- Talk:Large Synoptic Survey Telescope
- Talk:Larissa
- Talk:Las Campanas Observatory
- Talk:laser
- Talk:Laser Interferometer Space Antenna
- Talk:La Silla Observatory
- Talk:William Lassell
- Talk:Lassell ring
- Talk:last contact
- Talk:last quarter
- Talk:La Superba
- Talk:late heavy bombardment
- Talk:late-type galaxy
- Talk:late-type star
- Talk:latitude
- Talk:latitude variation
- Talk:LBV -> Talk:luminous blue variable
- Talk:L dwarf
- Talk:leap second
- Talk:leap year
- Talk:least circle of confusion -> Talk:astigmatism -> Talk:spherical aberration
- Talk:Henrietta Swan Leavitt
- Talk:Leda (moon)
- Talk:Georges Édouard Lemaître
- Talk:Lemaître universe
- Talk:lens
- Talk:Lense–Thirring effect -> Talk:frame dragging
- Talk:gravitational lens
- Talk:lenticula
- Talk:lenticular galaxy
- Talk:Leo (constellation)
- Talk:Leo Minor (constellation)
- Talk:Leonid meteors
- Talk:lepton
- Talk:lepton era
- Talk:Lepus
- Talk:Leto family
- Talk:Urbain Jean Joseph Le Verrier <-> Talk:Urbain Jean Joseph Leverrier
- Talk:Le Verrier Ring
- Talk:Comet Lexell (D/1770 L1)
- Talk:LHA -> Talk:local hour angle
- Talk:Libra (constellation)
- Talk:first point of Libra
- Talk:libration
- Talk:libration point -> Talk:Lagrangian point
- Talk:Lick Observatory
- Talk:light
- Talk:speed of light
- Talk:light bucket -> Talk:flux collector
- Talk:light cone
- Talk:light-curve
- Talk:light pollution
- Talk:light pressure -> Talk:radiation pressure
- Talk:light time
- Talk:light year
- Talk:limb
- Talk:limb brightening
- Talk:limb darkening
- Talk:limiting magnitude
- Talk:1
- Talk:2
- Talk:Lincoln Near-Earth Asteroid Research
- Talk:Bertil Lindblad
- Talk:Lindblad resonance
- Talk:linea
- Talk:LINEAR
- Talk:line blanketing
- Talk:line broadening
- Talk:line of apsides
- Talk:line of inversion -> Talk:magnetic inversion line
- Talk:line of nodes
- Talk:line profile
- Talk:liner
- Talk:line ratio
- Talk:line receiver
- Talk:line spectrum
- Talk:linewidth
- Talk:line wing
- Talk:lingula
- Talk:LISA -> Talk:Laser Interferometer Space Antenna
- Talk:LISA Pathfinder
- Talk:Lissajous orbit
- Talk:lithium star
- Talk:lithosiderite -> Talk:stony-iron meteorite
- Talk:lithosphere
- Talk:Little Dipper
- Talk:Little Dumbbell
- Talk:Liverpool Telescope
- Talk:L magnitude
- Talk:LMC -> Talk:Large Magellanic Cloud
- Talk:LMT -> Talk:Large Millimeter Telescope
- Talk:lobate ridge
- Talk:lobate scarp
- Talk:lobe
- Talk:1
- Talk:2
- Talk:local arm
- Talk:local bubble
- Talk:Local Group
- Talk:local hour angle
- Talk:local mean time
- Talk:local sidereal time
- Talk:local standard of rest
- Talk:local supercluster
- Talk:local thermodynamic equilibrium
- Talk:local time
- Talk:Lockman hole
- Talk:(Joseph) Norman Lockyer
- Talk:lodranite
- Talk:LOFAR -> Talk:Low Frequency Array
- Talk:LONEOS -> Talk:Lowell Observatory Near-Earth Object Search
- Talk:long-baseline interferometry
- Talk:longitude
- Talk:longitude at the epoch
- Talk:longitude of perigee
- Talk:longitude of perihelion
- Talk:longitude of the ascending node
- Talk:long-period comet
- Talk:long-period variable
- Talk:lookback time
- Talk:loop prominence
- Talk:Lorentz–Fitzgerald contraction
- Talk:Lorentz transformation
- Talk:Lost City meteorite
- Talk:(Alfred Charles) Bernard Lovell
- Talk:Lovell Telescope
- Talk:Percival Lowell
- Talk:Lowell Observatory
- Talk:Lowell Observatory Near-Earth Object Search
- Talk:lower culmination
- Talk:Low Frequency Array
- Talk:low-luminosity star
- Talk:low-mass star
- Talk:low surface brightness galaxy
- Talk:low-velocity star
- Talk:LRO -> Talk:Lunar Reconnaissance Orbiter
- Talk:LSR -> Talk:local standard of rest
- Talk:LSST -> Talk:Large Synoptic Survey Telescope
- Talk:LST -> Talk:local sidereal time
- Talk:LTP -> Talk:lunar transient phenomenon
- Talk:luminosity
- Talk:luminosity class
- Talk:luminosity evolution -> Talk:galaxy evolution
- Talk:luminosity function
- Talk:luminosity–volume test
- Talk:luminous arc
- Talk:luminous blue variable
- Talk:Luna (Moon probes)
- Talk:lunar eclipse
- Talk:lunar inequality
- Talk:Lunar Module
- Talk:Lunar Orbiter
- Talk:lunar parallax
- Talk:Lunar Prospector
- Talk:Lunar Reconnaissance Orbiter
- Talk:lunar theory -> Talk:lunar inequality
- Talk:lunar transient phenomenon
- Talk:lunation
- Talk:Knut Emil Lundmark
- Talk:lunisolar precession
- Talk:lunitidal interval
- Talk:Lunokhod
- Talk:Lupus
- Talk:Lutz–Kelker bias
- Talk:Willem ('William') Jacob Luyten
- Talk:l.y. -> Talk:light year
- Talk:Lydia family
- Talk:Lyman-α forest
- Talk:Lyman-break Galaxy
- Talk:Lyman limit
- Talk:Lyman series
- Talk:Lynx (constellation)
- Talk:Bernard Ferdinand Lyot
- Talk:Lyot filter -> Talk:birefringent filter
- Talk:Lyra (constellation)
- Talk:Lyrid meteors
- Talk:Lysithea
M2
edit- Talk:m -> Talk:apparent magnitude
- Talk:M -> Talk:Messier Catalogue
- Talk:M -> Talk:absolute magnitude
- Talk:MACHO
- Talk:Mach's principle
- Talk:macrospicules
- Talk:macroturbulence
- Talk:macula
- Talk:Maffei Galaxies
- Talk:Magdalena Ridge Observatory
- Talk:Magellan
- Talk:Magellanic Clouds
- Talk:Magellanic Stream
- Talk:Magellan Telescopes
- Talk:magma
- Talk:magnetar
- Talk:magnetic inversion line
- Talk:magnetic monopole
- Talk:magnetic star
- Talk:magnetic storm -> Talk:geomagnetic storm
- Talk:magnetic variable
- Talk:magnetobremsstrahlung
- Talk:magnetogram
- Talk:magnetohydrodynamics
- Talk:magnetopause
- Talk:magnetosheath
- Talk:magnetosphere
- Talk:magnetotail
- Talk:magnification
- Talk:magnitude
- Talk:magnitude of an eclipse
- Talk:main beam
- Talk:main-belt asteroid -> Talk:asteroid belt
- Talk:main lobe -> Talk:main beam
- Talk:main sequence
- Talk:major axis
- Talk:Maksutov telescope
- Talk:Malin-1
- Talk:Malmquist bias
- Talk:manganese–mercury star -> Talk:mercury–manganese star
- Talk:manganese star
- Talk:mantle
- Talk:many-body problem -> Talk:n-body problem
- Talk:mare (astronomy)
- Talk:Maria family
- Talk:Mariner
- Talk:Mariner Valley -> Talk:Valles Marineris
- Talk:Markab
- Talk:Markarian galaxy
- Talk:Mars (planet)
- Talk:Marsden group
- Talk:Mars Exploration Rover
- Talk:Mars Express
- Talk:Mars Global Surveyor
- Talk:Marshall Space Flight Center
- Talk:Mars Odyssey (2001 Mars Odyssey)
- Talk:Mars Pathfinder
- Talk:Mars probes
- Talk:Mars Reconnaissance Orbiter
- Talk:mascon
- Talk:maser
- Talk:maser amplifier
- Talk:maser source
- Talk:Nevil Maskelyne
- Talk:mass
- Talk:mass defect
- Talk:mass discrepancy
- Talk:mass function
- Talk:mass loss
- Talk:mass–luminosity relation
- Talk:mass–radius relation
- Talk:mass ratio
- Talk:mass-to-light ratio
- Talk:mass transfer
- Talk:John Cromwell Mather
- Talk:matter era
- Talk:Mauna Kea Observatories
- Talk:(Edward) Walter Maunder
- Talk:Maunder minimum
- Talk:maximum-entropy method
- Talk:James Clerk Maxwell
- Talk:Maxwell Gap
- Talk:Maxwell Montes
- Talk:Maxwell Telescope -> Talk:James Clerk Maxwell Telescope
- Talk:Mayall Telescope
- Talk:McDonald Observatory
- Talk:McIntosh scheme -> Talk:sunspot
- Talk:M-class asteroid
- Talk:McMath–Pierce Solar Telescope
- Talk:MDM Observatory
- Talk:mean anomaly
- Talk:mean daily motion
- Talk:mean density of matter
- Talk:mean equator
- Talk:mean equinox
- Talk:mean motion
- Talk:mean parallax -> Talk:statistical parallax
- Talk:mean place
- Talk:mean pole
- Talk:mean position -> Talk:mean place
- Talk:mean sidereal time
- Talk:mean solar day
- Talk:mean solar time
- Talk:mean sun
- Talk:mean time
- Talk:medium-band photometry
- Talk:megamaser
- Talk:megaregolith
- Talk:Megrez
- Talk:Melipal
- Talk:meniscus lens
- Talk:meniscus Schmidt telescope
- Talk:Menkalinan
- Talk:Menkar
- Talk:Mensa (constellation)
- Talk:mensa (planets)
- Talk:Donald Howard Menzel
- Talk:Merak
- Talk:Mercury
- Talk:mercury-manganese star
- Talk:Mercury Surface, Space Environment, Geochemistry, and Ranging
- Talk:celestial meridian
- Talk:terrestrial meridian
- Talk:meridian angle
- Talk:meridian astronomy
- Talk:meridian circle
- Talk:meridian passage -> Talk:meridian transit
- Talk:meridian telescope -> Talk:meridian circle -> Talk:transit circle -> Talk:transit instrument
- Talk:meridian transit
- Talk:MERLIN -> Talk:Multi-Element Radio-Linked Interferometer Network
- Talk:meson
- Talk:mesopause
- Talk:mesosiderite
- Talk:mesosphere
- Talk:MESSENGER -> Talk:Mercury Surface, Space Environment, Geochemistry, and Ranging
- Talk:Charles Joseph Messier
- Talk:Messier Catalogue
- Talk:Me star
- Talk:metagalaxy
- Talk:metal
- Talk:metallic hydrogen
- Talk:metal-poor star
- Talk:metal-rich star
- Talk:metastable state
- Talk:meteor
- Talk:Meteor Crater
- Talk:meteorite
- Talk:meteoroid
- Talk:meteor shower
- Talk:meteor storm
- Talk:meteor stream
- Talk:meteor swarm
- Talk:methanol maser
- Talk:Metis
- Talk:Metonic cycle
- Talk:Meudon Observatory
- Talk:Meyer group
- Talk:MHD -> Talk:magnetohydrodynamics
- Talk:Miaplacidus
- Talk:Mice (galaxies)
- Talk:Albert Abraham Michelson
- Talk:Michelson interferometer
- Talk:Michelson–Morley experiment
- Talk:Michelson stellar interferometer -> Talk:stellar interferometer
- Talk:microchannel plate detector
- Talk:microdensitometer
- Talk:microlensing
- Talk:micrometeorite
- Talk:micrometer (measuring instrument)
- Talk:micrometre
- Talk:micron
- Talk:micropore optics
- Talk:Microscopium (constellation)
- Talk:microturbulence
- Talk:Microvariability and Oscillations of Stars
- Talk:microvariable
- Talk:microwave background radiation
- Talk:microwaves
- Talk:Midcourse Space Experiment
- Talk:Mie scattering
- Talk:Milky Way
- Talk:millimetre-wave astronomy
- Talk:millimetre waves
- Talk:millisecond pulsar
- Talk:Mills cross
- Talk:Edward Arthur Milne
- Talk:Milne–Eddington approximation
- Talk:Mimas (moon)
- Talk:Mimosa -> Talk:Beta Crucis
- Talk:Hermann Minkowski
- Talk:Rudolph Leo Bernhard Minkowski
- Talk:minor axis
- Talk:minor planet -> Talk:asteroid
- Talk:Minor Planet Center
- Talk:Mintaka
- Talk:minute
- Talk:minute of arc <-> Talk:arcmin
- Talk:Mira
- Talk:Mirach
- Talk:Miranda (moon)
- Talk:Mira star
- Talk:Mirphak
- Talk:mirror
- Talk:mirror blank
- Talk:Mirzam
- Talk:missing mass
- Talk:Maria Mitchell
- Talk:Mittenzwey eyepiece
- Talk:mixing ratio
- Talk:Mizar
- Talk:MJD -> Talk:Modified Julian Date
- Talk:MK classification -> Talk:Morgan–Keenan classification
- Talk:MKK classification -> Talk:Morgan–Keenan classification
- Talk:M magnitude
- Talk:MMT Observatory
- Talk:mock Moon -> Talk:parselene
- Talk:mock Sun -> Talk:parhelion
- Talk:Modified Julian Date
- Talk:moldavite
- Talk:molecular cloud
- Talk:molecular hydrogen
- Talk:molecular line
- Talk:molecule
- Talk:Molonglo Radio Observatory
- Talk:moment of inertia
- Talk:MONET -> Talk:Monitoring Network of Telescopes
- Talk:Monitoring Network of Telescopes
- Talk:monocentric eyepiece
- Talk:Monoceros (constellation)
- Talk:monochromatic light
- Talk:monochromatic magnitude
- Talk:monochromator
- Talk:Monogem Ring
- Talk:monopole -> Talk:magnetic monopole
- Talk:mons (planets)
- Talk:month
- Talk:Monthly Notices of the Royal Astronomical Society
- Talk:Mont Mégantic Observatory -> Talk:Observatoire du Mont-Mégantic
- Talk:Moon
- Talk:Mopra Observatory
- Talk:Moreton wave
- Talk:William Wilson Morgan
- Talk:Morgan–Keenan classification
- Talk:Morgan's classification
- Talk:morning star
- Talk:MOST -> Talk:Microvariability and Oscillations of Stars
- Talk:mottles
- Talk:Mount Graham International Observatory
- Talk:mounting
- Talk:Mount Palomar Observatory -> Talk:Palomar Observatory
- Talk:Mount Stromlo and Siding Spring Observatories
- Talk:Mount Wilson classification -> Talk:sunspot
- Talk:Mount Wilson Observatory
- Talk:moustache -> Talk:Ellerman bomb
- Talk:moving cluster
- Talk:MRAO -> Talk:Mullard Radio Astronomy Observatory
- Talk:M region
- Talk:MRO -> Talk:Magdalena Ridge Observatory
- Talk:MSSSO -> Talk:Mount Stromlo and Siding Spring Observatories
- Talk:MS star
- Talk:1
- Talk:2
- Talk:M star
- Talk:MSX -> Talk:Midcourse Space Experiment
- Talk:Mu Cephei star
- Talk:Mullard Radio Astronomy Observatory
- Talk:Johann Müller -> Talk:Regiomontanus
- Talk:multi-beam receiver
- Talk:Multi-Element Radio-Linked Interferometer Network
- Talk:multiple star
- Talk:multiplet
- Talk:multi-ringed basin -> Talk:impact basin
- Talk:multiverse
- Talk:muon
- Talk:mural circle
- Talk:Musca (constellation)
N2
edit- Talk:nadir
- Talk:Nagler eyepiece
- Talk:Naiad
- Talk:Nal detector
- Talk:naked eye
- Talk:naked singularity
- Talk:nakhlite
- Talk:Nançay Radio Astronomy Observatory
- Talk:nanometre
- Talk:Naos
- Talk:narrow-band photometry
- Talk:NASA -> Talk:National Aeronautics and Space Administration
- Talk:NASA Infrared Telescope Facility
- Talk:Nasir Eddin -> Talk:al-Tusi
- Talk:Nasser Eddin -> Talk:al-Tusi
- Talk:Nasmyth focus
- Talk:National Aeronautics and Space Administration
- Talk:National Astronomy and Ionosphere Center -> Talk:Arecibo Observatory
- Talk:National Optical Astronomy Observatory
- Talk:National Radio Astronomy Observatory
- Talk:National Solar Observatory
- Talk:National Space Science Data Center
- Talk:The Nautical Almanac
- Talk:nautical twilight
- Talk:n-body problem
- Talk:NEA -> Talk:near-Earth asteroid
- Talk:neap tide
- Talk:near-Earth asteroid
- Talk:Near-Earth Asteroid Tracking
- Talk:near infrared
- Talk:NEAR Shoemaker
- Talk:near ultraviolet
- Talk:NEAT -> Talk:Near-Earth Asteroid Tracking
- Talk:nebula
- Talk:nebula filter
- Talk:nebular line
- Talk:nebular variable
- Talk:nebulosity
- Talk:negative eyepiece
- Talk:negative lens -> Talk:diverging lens
- Talk:Neptune (planet)
- Talk:Nereid (moon)
- Talk:Neumann lines
- Talk:neutral hydrogen
- Talk:neutral hydrogen line -> Talk:21-centimetre line
- Talk:neutral point
- Talk:neutrino
- Talk:neutrino astronomy
- Talk:neutron
- Talk:neutron degeneracy
- Talk:neutron star
- Talk:Simon Newcomb
- Talk:New General Catalogue
- Talk:New Horizons
- Talk:New Millennium Program
- Talk:new Moon
- Talk:New Style date
- Talk:New Technology Telescope
- Talk:newton
- Talk:Isaac Newton
- Talk:Newtonian–Cassegrain telescope
- Talk:Newtonian focus
- Talk:Newtonian telescope
- Talk:Newton's law of gravitation
- Talk:Newton's laws of motion
- Talk:N galaxy
- Talk:NGC -> Talk:New General Catalogue
- Talk:nickel–iron meteorite -> Talk:iron meteorite
- Talk:Nicol prism
- Talk:nightglow -> Talk:airglow
- Talk:night sky brightness
- Talk:night vision
- Talk:Nix Olympica -> Talk:Olympus Mons
- Talk:NLC -> Talk:noctilucent clouds
- Talk:nm -> Talk:nanometre
- Talk:N magnitude
- Talk:NOAO -> Talk:National Optical Astronomy Observatory
- Talk:Nobeyama Radio Observatory
- Talk:noble gas
- Talk:noctilucent clouds
- Talk:nocturnal
- Talk:nodal line
- Talk:node
- Talk:nodical month -> Talk:draconic month
- Talk:non-baryonic matter
- Talk:non-gravitational force
- Talk:non-radial pulsation
- Talk:non-thermal radiation
- Talk:Nordic Optical Telescope
- Talk:Norma (constellation)
- Talk:normal astrograph
- Talk:North America Nebula
- Talk:Northern Coalsack -> Talk: Great Rift
- Talk:Northern Cross -> Talk:Cygnus (constellation)
- Talk:northern lights -> Talk:aurora (astronomy)
- Talk:North Galactic Spur
- Talk:north polar distance
- Talk:North Polar Sequence
- Talk:North Star -> Talk:Polaris
- Talk:nova
- Talk:nova-like variable
- Talk:NPD -> Talk:north polar distance
- Talk:NRAO -> Talk:National Radio Astronomy Observatory
- Talk:NS -> Talk:New Style date
- Talk:NSO -> Talk:National Solar Observatory
- Talk:NSSDC -> Talk:National Space Science Data Center
- Talk:N star -> Talk:carbon star
- Talk:NTT -> Talk:New Technology Telescope
- Talk:Nubecula Major -> Talk:Magellanic Clouds
- Talk:Nubecula Minor -> Talk:Magellanic Clouds
- Talk:nuclear fusion
- Talk:nuclear reaction
- Talk:nuclear time-scale
- Talk:nucleon
- Talk:nucleosynthesis
- Talk:atomic nucleus
- Talk:cometary nucleus
- Talk:galactic nucleus
- Talk:null geodesic
- Talk:number evolution -> Talk:galaxy evolution
- Talk:Nunki
- Talk:nutation
- Talk:nutation in right ascension -> Talk:equation of the equinoxes
- Talk:Nysa family
O2
edit- Talk:OAO -> Talk:Orbiting Astronomical Observatory
- Talk:OB association
- Talk:Oberon
- Talk:object glass
- Talk:objective
- Talk:objective grating
- Talk:objective prism
- Talk:oblateness
- Talk:oblate spheroid -> Talk:spheroid
- Talk:oblique rotator
- Talk:obliquity of the ecliptic
- Talk:Observatoire du mont Mégantic
- Talk:observatory
- Talk:occultation
- Talk:occulting bar
- Talk:occulting disk
- Talk:oceanus
- Talk:OC star
- Talk:octahedrite
- Talk:Octans (constellation)
- Talk:ocular -> Talk:eyepiece
- Talk:Oe star
- Talk:off-axis guider
- Talk:Of star
- Talk:o.g. -> Talk:object glass
- Talk:OH–IR source
- Talk:OH line
- Talk:OH maser
- Talk:OHP -> Talk:Haute-Provence Observatory
- Talk:Heinrich Wilhelm Matthäus Olbers
- Talk:Olbers' paradox
- Talk:Old Style date
- Talk:Oljato (asteroid)
- Talk:Olympus Mons
- Talk:O magnitude
- Talk:Omega Centauri
- Talk:Omega Nebula
- Talk:Onsala Space Observatory
- Talk:ON star
- Talk:Jan Hendrik Oort
- Talk:Oort Cloud
- Talk:Oort's constants
- Talk:Oosterhoff group
- Talk:Ootacamund Radio Astronomy Centre
- Talk:opacity
- Talk:open cluster
- Talk:open universe
- Talk:Ophelia (moon)
- Talk:Ophiuchid meteors
- Talk:Ophiuchus (constellation)
- Talk:Ernst Julius Öpik
- Talk:Oppenheimer–Volkoff limit
- Talk:Opportunity (Mars rover)
- Talk:opposition (astronomy)
- Talk:opposition effect
- Talk:optical axis
- Talk:optical depth
- Talk:optical double
- Talk:optical flat
- Talk:optical glass
- Talk:optical interferometer
- Talk:optical libration
- Talk:optical pathlength
- Talk:optical pulsar
- Talk:optical thickness -> Talk:optical depth
- Talk:optical wedge
- Talk:optics
- Talk:orbit
- Talk:orbital elements
- Talk:orbital velocity
- Talk:Orbiting Astronomical Observatory
- Talk:Orbiting Solar Observatory
- Talk:ordinary chondrite
- Talk:organic molecule
- Talk:Orgueil meteorite
- Talk:Orientale Basin
- Talk:Orion (constellation)
- Talk:Orion Arm
- Talk:Orion Association
- Talk:Orionid meteors
- Talk:Orion Molecular Clouds
- Talk:Orion Nebula
- Talk:Orion Spur
- Talk:Orion variable
- Talk:ORM -> Talk:Roque de los Muchachos Observatory
- Talk:orrery
- Talk:orthoscopic eyepiece
- Talk:OS -> Talk:Old Style date
- Talk:oscillating universe
- Talk:osculating elements
- Talk:osculating orbit
- Talk:OSO -> Talk:Orbiting Solar Observatory
- Talk:O star
- Talk:OT -> Talk:Teide Observatory
- Talk:outgassing
- Talk:1
- Talk:2
- Talk:overcontact binary
- Talk:oversampling
- Talk:overshooting
- Talk:overtone mode
- Talk:OVV quasar -> Talk:optically violently variable quasar -> Talk:blazar
- Talk:Owens Valley Radio Observatory
- Talk:Owl Nebula
- Talk:oxygen burning
- Talk:ozonosphere
P2
edit- Talk:PA -> Talk:position angle
- Talk:PAH -> Talk:polycyclic aromatic hydrocarbon
- Talk:pair annihilation
- Talk:pair production
- Talk:palimpsest
- Talk:Pallas (asteroid)
- Talk:pallasite
- Talk:Palomar Observatory
- Talk:Palomar Observatory Sky Survey
- Talk:palus
- Talk:Pan (moon)
- Talk:Pandora (moon)
- Talk:Pan-STARRS
- Talk:parabola
- Talk:parabolic antenna
- Talk:parabolic comet
- Talk:parabolic orbit
- Talk:parabolic velocity
- Talk:paraboloid
- Talk:parallactic angle
- Talk:parallactic ellipse
- Talk:parallactic inequality
- Talk:parallactic motion
- Talk:parallax
- Talk:parametric amplifier
- Talk:Paranal Observatory
- Talk:paraxial
- Talk:parent isotope
- Talk:parfocal
- Talk:parhelion
- Talk:Paris Observatory
- Talk:Parkes Observatory
- Talk:parsec
- Talk:parselene
- Talk:William Parsons -> Talk:Third Earl of Rosse
- Talk:partial eclipse
- Talk:particle -> Talk:elementary particle
- Talk:pascal (unit)
- Talk:Paschen–Back effect
- Talk:Paschen series
- Talk:Pasiphae (moon)
- Talk:passband
- Talk:past light cone -> Talk:light cone
- Talk:patera
- Talk:pathlength -> Talk:optical pathlength
- Talk:Paul Wild Observatory
- Talk:Pavo (constellation)
- Talk:Cecilia Helena Payne-Gaposchkin
- Talk:pc -> Talk:parsec
- Talk:P-class asteroid
- Talk:P Cygni line profile
- Talk:P Cygni star -> Talk:S Doradus star
- Talk:Peacock (star)
- Talk:peculiar galaxy
- Talk:peculiar motion
- Talk:peculiar star
- Talk:peculiar velocity
- Talk:pedestal crater
- Talk:Peekskill meteorite
- Talk:Pegasus (constellation)
- Talk:Pele
- Talk:Pelican Nebula
- Talk:Penrose process
- Talk:penumbra
- Talk:1
- Talk:2
- Talk:penumbral eclipse
- Talk:Arno Allan Penzias
- Talk:perfect cosmological principle
- Talk:peri-
- Talk:periapsis
- Talk:periastron
- Talk:periastron effect
- Talk:pericentre
- Talk:perigee
- Talk:perihelion
- Talk:time of perihelion passage
- Talk:orbital period
- Talk:period–age relation
- Talk:period–colour relation
- Talk:period–density relation
- Talk:periodic comet
- Talk:periodic orbit
- Talk:periodic perturbation
- Talk:period–luminosity–colour relation
- Talk:period–luminosity relation
- Talk:period–mass relation
- Talk:period–radius relation
- Talk:period–spectrum relation
- Talk:Perseid meteors
- Talk:Perseus (constellation)
- Talk:Perseus A
- Talk:Perseus Arm
- Talk:Perseus Cluster
- Talk:personal equation
- Talk:perturbation
- Talk:Petzval surface
- Talk:Pfund series
- Talk:PHA -> Talk:Potentially Hazardous Asteroid
- Talk:Phad
- Talk:Phaethon (asteroid)
- Talk:phase
- Talk:1
- Talk:2
- Talk:phase angle
- Talk:phased array
- Talk:phase defect
- Talk:phase diagram
- Talk:phase difference
- Talk:phase rotator
- Talk:phase-switching interferometer
- Talk:phase transition -> Talk:inflationary universe
- Talk:Phecda -> Talk:Phad
- Talk:Pherkad
- Talk:Phillips bands
- Talk:Phobos (moon)
- Talk:Phobos probes
- Talk:Phocaea group
- Talk:Phoebe (moon)
- Talk:Phoenicid meteors
- Talk:Phoenix (constellation)
- Talk:Phoenix (Mars lander)
- Talk:Pholus (asteroid)
- Talk:photino
- Talk:photocathode
- Talk:photocell -> Talk:photoelectric cell
- Talk:photocentre
- Talk:1
- Talk:2
- Talk:photoconductive cell
- Talk:photodissociation
- Talk:photodissociation region
- Talk:photoelectric cell
- Talk:photoelectric magnitude
- Talk:photoelectric photometer
- Talk:photographic amplification
- Talk:photographic emulsion
- Talk:photographic magnitude
- Talk:photographic zenith tube
- Talk:photoheliograph
- Talk:photoionization
- Talk:photometer
- Talk:photometric binary
- Talk:photometric parallax
- Talk:photometric standard -> Talk:standard star
- Talk:photometry
- Talk:photomultiplier
- Talk:photon
- Talk:photon sphere
- Talk:photopolarimeter -> Talk:polarimeter
- Talk:photosphere
- Talk:photovisual magnitude
- Talk:photovoltaic detector
- Talk:physical albedo -> Talk:geometrical albedo
- Talk:physical double
- Talk:physical libration
- Talk:Giuseppe Piazzi
- Talk:Pic du Midi Observatory
- Talk:Edward Charles Pickering
- Talk:William Henry Pickering
- Talk:Pickering Series
- Talk:Pico Veleta
- Talk:Pictor (constellation)
- Talk:pincushion distortion
- Talk:Pinwheel Galaxy
- Talk:pion
- Talk:Pioneer
- Talk:Pioneer Venus
- Talk:Pipe Nebula
- Talk:Pisces (constellation)
- Talk:Piscid meteors
- Talk:Piscis Austrinid meteors
- Talk:Piscis Austrinus (constellation)
- Talk:pitch angle
- Talk:pixel
- Talk:plage
- Talk:Planck (spacecraft)
- Talk:Planck constant
- Talk:Planck era
- Talk:Planck's law
- Talk:planemo
- Talk:planet
- Talk:planetarium
- Talk:planetary aberration
- Talk:planetary aspect -> Talk:aspect
- Talk:planetary migration
- Talk:planetary nebula
- Talk:planetary precession
- Talk:planetesimal
- Talk:planetoid -> Talk:asteroid -> Talk:Giuseppe Piazzi
- Talk:planetology
- Talk:planisphere
- Talk:planitia
- Talk:planoconcave lens
- Talk:planoconvex lens
- Talk:planum
- Talk:John Stanley Plaskett
- Talk:Plaskett's Star
- Talk:plasma
- Talk:plasmapause
- Talk:plasmasphere
- Talk:plasma tail -> Talk:cometary tail
- Talk:Plateau de Bure
- Talk:plate centre
- Talk:plate constants
- Talk:plate-measuring machine
- Talk:plate scale
- Talk:plate tectonics
- Talk:Platonic year
- Talk:PLC relation -> Talk:period–luminosity–colour relation
- Talk:Pleiades
- Talk:plerion
- Talk:Plössl eyepiece
- Talk:Plough (asterism)
- Talk:PL relation -> Talk:period–luminosity relation
- Talk:plume
- Talk:1
- Talk:2
- Talk:Plutino
- Talk:Pluto
- Talk:P magnitude
- Talk:Pockels cell
- Talk:Norman Robert Pogson
- Talk:Pogson ratio
- Talk:Pogson scale
- Talk:Pogson step method
- Talk:(Jules) Henri Poincaré
- Talk:Pointers
- Talk:point source
- Talk:point-spread function
- Talk:polar -> Talk:AM Herculis star -> Talk:DQ Herculis star
- Talk:polar axis
- Talk:polar cap
- Talk:polar diagram
- Talk:polar distance
- Talk:polar flattening
- Talk:polarimeter
- Talk:polarimetry -> Talk:polarization
- Talk:Polaris
- Talk:polarization
- Talk:polar motion
- Talk:polar orbit
- Talk:polar plume -> Talk:coronal plume
- Talk:polar ring galaxy
- Talk:polar sequence
- Talk:polar wandering
- Talk:pole
- Talk:pole star
- Talk:Pollux
- Talk:polycyclic aromatic hydrocarbon
- Talk:John Pond
- Talk:Jean Louis Pons
- Talk:stellar population
- Talk:Population I
- Talk:Population II
- Talk:Population III
- Talk:pore
- Talk:Porrima
- Talk:Porro prism
- Talk:Portia (moon)
- Talk:positional astronomy -> Talk:astrometry -> Talk:meridian astronomy
- Talk:position angle
- Talk:position-angle effect
- Talk:position circle
- Talk:position micrometer -> Talk:filar micrometer
- Talk:positive lens -> Talk:converging lens
- Talk:POSS -> Talk:Palomar Observatory Sky Survey
- Talk:post-nova
- Talk:potassium–argon method
- Talk:potential hazardous asteroid
- Talk:power spectrum
- Talk:Poynting–Robertson effect
- Talk:PPM Star Catalogue
- Talk:p-process
- Talk:Praesepe
- Talk:preceding
- Talk:precession
- Talk:precession constant
- Talk:precession of the equinoxes
- Talk:precursor pulse
- Talk:pre-nova
- Talk:pressure broadening
- Talk:Príbram meteorite
- Talk:primary cosmic ray
- Talk:primary minimum
- Talk:primary mirror
- Talk:prime focus
- Talk:prime meridian
- Talk:prime vertical
- Talk:primordial fireball
- Talk:primordial galaxy
- Talk:Principia
- Talk:principle of equivalence -> Talk:equivalence principle
- Talk:prism
- Talk:prismatic astrolabe
- Talk:probable error
- Talk:Procyon
- Talk:prograde motion -> Talk:direct motion
- Talk:prolate spheroid -> Talk:spheroid
- Talk:Prometheus (moon)
- Talk:prominence
- Talk:prominence spectroscope
- Talk:promontorium
- Talk:proper motion
- Talk:proper time
- Talk:proplyd
- Talk:proportional counter
- Talk:Prospero (moon)
- Talk:Proteus (moon)
- Talk:protogalaxy
- Talk:proton
- Talk:proton–proton reaction
- Talk:protoplanet
- Talk:protoplanetary nebula
- Talk:1
- Talk:2
- Talk:protostar
- Talk:protosun
- Talk:Proxima Centauri
- Talk:p-spot
- Talk:Ptolemaic system
- Talk:Ptolemy <-> Talk:Claudius Ptolemaeus
- Talk:Publications of the Astronomical Society of the Pacific
- Talk:Puck (moon)
- Talk:Pulcherrima -> Talk:Izar
- Talk:pulsar
- Talk:pulsating variable
- Talk:pulsation mode
- Talk:pulse broadening
- Talk:pulse profile
- Talk:pulse width
- Talk:Pup (Sirius B)
- Talk:pupil
- Talk:Puppid–Velid meteors
- Talk:Puppis (constellation)
- Talk:Purkinje effect
- Talk:PV Telescopii star
- Talk:Pyxis
- Talk:PZT -> Talk:photographic zenith tube
Q2
edit- Talk:Q-class asteroid
- Talk:Q magnitude
- Talk:QSO -> Talk:quasi-stellar object
- Talk:QSS -> Talk:quasi-stellar radio source
- Talk:quadrant
- Talk:Quadrantid meteors
- Talk:quadrature
- Talk:quadrupole
- Talk:quantum
- Talk:quantum cosmology
- Talk:quantum efficiency
- Talk:quantum gravitation
- Talk:quantum theory
- Talk:Quaoar
- Talk:quark
- Talk:quark star
- Talk:quasar
- Talk:quasi-stellar object
- Talk:quasi-stellar radio source
- Talk:quiescent prominence
- Talk:quiet sun
- Talk:quintessence -> Talk:dark energy
R2
edit- Talk:RA -> Talk:right ascension
- Talk:radar astronomy
- Talk:radar meteor
- Talk:radial pulsation
- Talk:radial velocity
- Talk:radial-velocity spectrometer
- Talk:radian
- Talk:radiant
- Talk:radiation
- Talk:radiation belt
- Talk:radiation era
- Talk:radiation laws -> Talk:Planck's law -> Talk:Stefan–Boltzmann law -> Talk:Wien's displacement law
- Talk:radiation pressure
- Talk:radiation temperature
- Talk:radiative equilibrium
- Talk:radiative recombination -> Talk:free–bound transition
- Talk:radiative transfer
- Talk:radiative zone
- Talk:radioactive age dating
- Talk:radio astrometry
- Talk:RadioAstron
- Talk:radio astronomy
- Talk:radio galaxy
- Talk:radiogenic
- Talk:radioheliograph
- Talk:radio interferometer
- Talk:radio jet -> Talk:jet (astronomy)
- Talk:radio meteor
- Talk:radiometer
- Talk:radiometric dating -> Talk:radioactive age dating
- Talk:radionuclide
- Talk:radio source
- Talk:radio star
- Talk:radio telescope
- Talk:radio waves
- Talk:radio window
- Talk:radius–luminosity relation
- Talk:radius of curvature
- Talk:radius vector
- Talk:Raman effect
- Talk:Ramaty High-Energy Solar Spectroscopic Imager
- Talk:rampart crater
- Talk:Ramsden disk
- Talk:Ramsden eyepiece
- Talk:Ranger (Moon probes)
- Talk:RAS -> Talk:Royal Astronomical Society
- Talk:Rasalgethi
- Talk:Rasalhague
- Talk:Ra-Shalom (asteroid)
- Talk:R association
- Talk:raster
- Talk:raster scan
- Talk:RAS thread
- Talk:RATAN-600
- Talk:Rayleigh criterion
- Talk:Rayleigh–Jeans formula
- Talk:Rayleigh limit -> Talk:Rayleigh criterion
- Talk:Rayleigh number
- Talk:Rayleigh scattering
- Talk:crater rays
- Talk:R Canis Majoris star
- Talk:R-class asteroid
- Talk:R Coronae Borealis star
- Talk:Grote Reber
- Talk:receiver
- Talk:1
- Talk:2
- Talk:reciprocity failure
- Talk:recombination
- Talk:recombination epoch
- Talk:recombination line
- Talk:rectangular coordinates
- Talk:recurrent nova
- Talk:recycled pulsar
- Talk:reddening
- Talk:red dwarf
- Talk:red giant
- Talk:Red Planet -> Talk:Mars (planet)
- Talk:redshift
- Talk:redshift–distance relation
- Talk:redshift–magnitude relation
- Talk:Red Spot -> Talk:Great Red Spot
- Talk:reduced proper motion
- Talk:red variable
- Talk:reference frame -> Talk:frame of reference
- Talk:reference star
- Talk:reflectance spectrum
- Talk:reflecting telescope
- Talk:reflection effect
- Talk:reflection grating
- Talk:reflection nebula
- Talk:reflection variable
- Talk:reflector -> Talk:reflecting telescope
- Talk:refracting telescope
- Talk:atmospheric refraction
- Talk:refractive index
- Talk:refractor -> Talk:refracting telescope
- Talk:refractory
- Talk:regio
- Talk:Regiomontanus
- Talk:regmaglypt
- Talk:regolith
- Talk:regression of nodes
- Talk:Regulus
- Talk:relative orbit
- Talk:relative sunspot number
- Talk:relativistic beaming
- Talk:relativistic velocity
- Talk:relativity
- Talk:relaxation time
- Talk:remote sensing
- Talk:réseau
- Talk:residuals
- Talk:resolution -> Talk:resolving power
- Talk:resolving power
- Talk:resonance
- Talk:resonance line
- Talk:resonant scattering
- Talk:rest mass
- Talk:restricted three-body problem
- Talk:retardation
- Talk:retardation plate -> Talk:wave plate
- Talk:reticle
- Talk:Reticulum (constellation)
- Talk:reticulum (planets)
- Talk:retrograde motion
- Talk:reversing layer
- Talk:revolution
- Talk:RFT -> Talk:richest-field telescope
- Talk:RGO -> Talk:Royal Greenwich Observatory
- Talk:RGU photometry
- Talk:Rhea (moon)
- Talk:RHESSI -> Talk:Ramaty High-Energy Solar Spectroscopic Imager
- Talk:Rho Cassiopeiae star
- Talk:Rho Ophiuchi Nebula
- Talk:Richardson–Lucy algorithm
- Talk:richest-field telescope
- Talk:Rigel
- Talk:right ascension
- Talk:Rigil Kentaurus -> Talk:Alpha Centauri
- Talk:rille (Moon)
- Talk:rima
- Talk:planetary ring
- Talk:ring arcs
- Talk:ring galaxy
- Talk:Ring Nebula
- Talk:rise time
- Talk:rising
- Talk:George Willis Ritchey
- Talk:Ritchey–Chrétien telescope
- Talk:R magnitude
- Talk:Robertson–Walker metric
- Talk:Roche limit
- Talk:Roche lobe
- Talk:ROE -> Talk:Royal Observatory, Edinburgh
- Talk:Ole Christensen Römer
- Talk:Olaus Christensen Römer -> Talk:Ole Christensen Römer
- Talk:Ronchi test
- Talk:Rood–Sastry type
- Talk:roof prism
- Talk:Roque de los Muchachos Observatory
- Talk:Rosalind (moon)
- Talk:Rosat
- Talk:Rosetta
- Talk:Rosette Nebula
- Talk:Frank Elmore Ross
- Talk:Third Earl of Rosse <-> Talk:William Parsons
- Talk:Rosseland mean opacity
- Talk:Bruno Benedetto Rossi
- Talk:Rossiter effect
- Talk:Rossi X-ray Timing Explorer
- Talk:rotating variable
- Talk:rotation
- Talk:rotation curve
- Talk:rotation effect -> Talk:Rossiter effect
- Talk:rotation measure
- Talk:Royal Astronomical Society
- Talk:Royal Greenwich Observatory
- Talk:Royal Observatory, Edinburgh
- Talk:r-process
- Talk:RR Lyrae star
- Talk:RRs variable -> Talk:Delta Scuti star
- Talk:RR Telescopii star
- Talk:RS Canum Venaticorum star
- Talk:R star -> Talk:carbon star
- Talk:Rubin–Ford effect
- Talk:runaway star
- Talk:rupes
- Talk:Henry Norris Russell
- Talk:Russell–Vogt theorem -> Talk:Vogt–Russell theorem
- Talk:RV Tauri star
- Talk:RW Aurigae star
- Talk:RXTE -> Talk:Rossi X-ray Timing Explorer
- Talk:Martin Ryle
- Talk:Ryle Telescope
S2
edit- Talk:SAAO -> Talk:South African Astronomical Observatory
- Talk:Sabik
- Talk:Sachs–Wolfe effect
- Talk:Sacramento Peak Observatory
- Talk:Carl Edward Sagan
- Talk:Sagitta (constellation)
- Talk:Sagittarius (constellation)
- Talk:Sagittarius A
- Talk:Sagittarius Arm
- Talk:Sagittarius Dwarf Galaxy
- Talk:Saha ionization equation
- Talk:Sakigake
- Talk:Salpeter function -> Talk:initial mass function
- Talk:Salpeter process -> Talk:triple-alpha process
- Talk:SALT -> Talk:South African Large Telescope
- Talk:SAMPEX -> Talk:Solar, Anomalous, and Magnetospheric Particle Explorer
- Talk:Allan Rex Sandage
- Talk:SAO -> Talk:Smithsonian Astrophysical Observatory
- Talk:SAO Catalog -> Talk:Smithsonian Astrophysical Observatory Star Catalog
- Talk:saros
- Talk:SAS -> Talk:Small Astronomy Satellite
- Talk:satellite
- Talk:Saturn (planet)
- Talk:Saturn Nebula
- Talk:scale height
- Talk:scattered-disk object
- Talk:scatter ellipse
- Talk:scattering
- Talk:Scheat
- Talk:Schechter function
- Talk:Schedar -> Talk:Shedir
- Talk:Christoph Scheiner
- Talk:Giovanni Virginio Schiaparelli
- Talk:schiefspiegler telescope
- Talk:Maarten Schmidt
- Talk:Schmidt camera
- Talk:Schmidt–Cassegrain telescope
- Talk:Schönberg–Chandrasekhar limit -> Talk:Chandrasekhar–Schönberg limit
- Talk:Schröter effect
- Talk:(Samuel) Heinrich Schwabe
- Talk:Karl Schwarzschild
- Talk:Schwarzschild black hole
- Talk:Schwarzschild radius
- Talk:Schwarzschild telescope
- Talk:Comet 29P/Schwassmann–Wachmann 1
- Talk:scintillation
- Talk:scintillation counter
- Talk:S-class asteroid
- Talk:Sco-Cen Association
- Talk:scopulus
- Talk:Scorpius (constellation)
- Talk:Scorpius X-1
- Talk:Scotch mount
- Talk:SC star -> Talk:S star
- Talk:SCT -> Talk:Schmidt–Cassegrain telescope
- Talk:Sculptor (constellation)
- Talk:Sculptor group
- Talk:Scutum (constellation)
- Talk:SDO -> Talk:Solar Dynamics Observatory
- Talk:S Doradus star
- Talk:SDSS photometry
- Talk:Search for Extraterrestrial Intelligence
- Talk:Seashell Galaxy
- Talk:season
- Talk:(Pietro) Angelo Secchi
- Talk:Secchi classification
- Talk:second
- Talk:leap second
- Talk:secondary cosmic ray
- Talk:secondary crater
- Talk:secondary minimum
- Talk:secondary mirror
- Talk:second contact
- Talk:second of arc
- Talk:secular
- Talk:secular acceleration
- Talk:secular parallax
- Talk:secular perturbation
- Talk:secular variable
- Talk:seeing
- Talk:segmented mirror
- Talk:selected areas -> Talk:Kapteyn Selected Areas
- Talk:selective absorption
- Talk:Selene (Moon probe)
- Talk:selenology
- Talk:self-absorption
- Talk:semidetached binary
- Talk:semidiameter
- Talk:semi-forbidden line -> Talk:forbidden line
- Talk:semimajor axis
- Talk:semiregular variable
- Talk:sensitivity
- Talk:separation
- Talk:Serpens (constellation)
- Talk:Serrurier truss
- Talk:Setebos
- Talk:SETI -> Talk:Search for Extraterrestrial Intelligence
- Talk:setting
- Talk:setting circle
- Talk:Seven Sisters -> Talk:Pleiades
- Talk:Sextans (constellation)
- Talk:sextant
- Talk:Carl Keenan Seyfert
- Talk:Seyfert galaxy
- Talk:Seyfert's Sextet
- Talk:Shack–Hartmann test -> Talk:Hartmann test
- Talk:shadow bands
- Talk:shadow transit
- Talk:Shapiro delay
- Talk:Harlow Shapley
- Talk:Shapley Concentration -> Talk:supercluster
- Talk:shatter cone
- Talk:Shaula
- Talk:Shedir
- Talk:shell burning
- Talk:shell galaxy
- Talk:shell star
- Talk:shepherd moon
- Talk:shergottite
- Talk:shield volcano
- Talk:shock metamorphism
- Talk:Eugene Merle Shoemaker
- Talk:Comet Shoemaker–Levy 9 (D/1993 F2)
- Talk:shooting star -> Talk:meteor
- Talk:short-period comet
- Talk:short-period variable
- Talk:Sickle (asterism)
- Talk:side lobe
- Talk:sidereal
- Talk:sidereal day
- Talk:sidereal month
- Talk:sidereal period
- Talk:sidereal rate
- Talk:sidereal time
- Talk:sidereal year
- Talk:siderite -> Talk:iron meteorite
- Talk:siderolite -> Talk:stony-iron meteorite
- Talk:siderophyre
- Talk:siderostat
- Talk:Siding Spring Observatory
- Talk:Sigma Octantis
- Talk:signal-to-noise ratio -> Talk:sensitivity
- Talk:Sikhote–Alin meteorite
- Talk:silicon burning
- Talk:silicon star
- Talk:silvering
- Talk:SIMBAD
- Talk:SIM PlanetQuest
- Talk:single-lined binary
- Talk:singularity
- Talk:Sinope (moon)
- Talk:sinuous rille
- Talk:sinus
- Talk:SiO maser
- Talk:Sirius
- Talk:Sirrah
- Talk:Willem de Sitter
- Talk:SI units
- Talk:six-colour system
- Talk:61 Cygni
- Talk:SKA -> Talk:Square Kilometre Array
- Talk:sky brightness
- Talk:Skylab
- Talk:Earl Carl Slipher
- Talk:Vesto Melvin Slipher
- Talk:Sloan Digital Sky Survey
- Talk:slow nova
- Talk:slow pulsator
- Talk:SMA -> Talk:Submillimeter Array
- Talk:Small Astronomy Satellite
- Talk:small circle
- Talk:Small Magellanic Cloud
- Talk:SMART-1
- Talk:SMC -> Talk:Small Magellanic Cloud
- Talk:Smithsonian Astrophysics Observatory
- Talk:Smithsonian Astrophysics Observatory Star Catalog
- Talk:SMM -> Talk:Solar Maximum Mission
- Talk:George Fitzgerald Smoot III
- Talk:SNC meteorites
- Talk:SNR -> Talk:supernova remnant
- Talk:SNU -> Talk:solar neutrino unit
- Talk:SOAR -> Talk:Southern Astrophysical Research telescope
- Talk:SOFIA -> Talk:Stratospheric Observatory for Infrared Astronomy
- Talk:soft gamma-ray repeater
- Talk:soft X-rays
- Talk:SO galaxy -> Talk:lenticular galaxy
- Talk:SOHO -> Talk:Solar and Heliospheric Observatory
- Talk:Sojourner
- Talk:Solar, Anomalous, and Magnetospheric Particle Explorer
- Talk:solar activity
- Talk:Solar and Heliospheric Observatory
- Talk:solar antapex
- Talk:solar apex
- Talk:solar atmosphere
- Talk:solar constant
- Talk:solar cycle -> Talk:sunspot cycle
- Talk:solar day
- Talk:Solar Dynamics Observatory
- Talk:solar dynamo
- Talk:solar eclipse
- Talk:solar flare
- Talk:solar interior
- Talk:solar irradiance
- Talk:solar mass
- Talk:solar maximum
- Talk:Solar Maximum Mission
- Talk:solar minimum
- Talk:solar motion
- Talk:solar nebula
- Talk:solar neutrino unit
- Talk:Solar Orbiter
- Talk:solar oscillations -> Talk:helioseismology
- Talk:solar parallax
- Talk:Solar System
- Talk:solar telescope
- Talk:solar–terrestrial relations
- Talk:Solar Terrestrial Relations Observatory
- Talk:solar time
- Talk:solar tower
- Talk:solar wind
- Talk:solar year
- Talk:solid Schmidt telescope
- Talk:solstice
- Talk:solstitial colure
- Talk:Sombrero Galaxy
- Talk:Sothic cycle
- Talk:source count
- Talk:South African Astronomical Observatory
- Talk:South Atlantic Anomaly
- Talk:Southern African Large Telescope
- Talk:Southern Astrophysical Research Telescope
- Talk:Southern Cross
- Talk:southern lights
- Talk:Southern Reference Stars
- Talk:Southern Sky Survey
- Talk:South Pole Aitken Basin
- Talk:curvature of space -> Talk:curvature of spacetime
- Talk:space motion
- Talk:space probe
- Talk:space reddening -> Talk:interstellar absorption
- Talk:Space Telescope Science Institute
- Talk:spacetime
- Talk:space velocity
- Talk:Spacewatch
- Talk:space weather
- Talk:spallation
- Talk:spark chamber
- Talk:spec. -> Talk:speculum metal
- Talk:Special Astrophysical Observatory
- Talk:special theory of relativity
- Talk:speckle interferometry
- Talk:spectral classification
- Talk:spectral index
- Talk:spectral line
- Talk:spectral type
- Talk:spectrogram
- Talk:spectrograph
- Talk:spectroheliogram
- Talk:spectroheliograph
- Talk:spectrohelioscope
- Talk:spectrometer
- Talk:spectrophotometer
- Talk:spectrophotometry
- Talk:spectropolarimetry
- Talk:spectroscope
- Talk:spectroscopic binary
- Talk:spectroscopic parallax
- Talk:spectroscopy
- Talk:spectrum
- Talk:1
- Talk:2
- Talk:spectrum binary
- Talk:spectrum variable -> Talk:Alpha2 Canum Venaticorum
- Talk:speculum metal
- Talk:Harold Spencer Jones
- Talk:spherical aberration
- Talk:spherical albedo -> Talk:Bond albedo
- Talk:spherical astronomy
- Talk:spherical coordinates
- Talk:spheroid
- Talk:Spica
- Talk:spicule
- Talk:spider
- Talk:spin
- Talk:spinar
- Talk:spin casting
- Talk:Spindle Galaxy
- Talk:spin-down
- Talk:spin–orbit coupling
- Talk:spin temperature
- Talk:spiral arm
- Talk:spiral galaxy
- Talk:Spirit (Mars rover)
- Talk:Lyman Spitzer, Jr
- Talk:Spitzer Space Telescope
- Talk:spokes
- Talk:sporadic meteor
- Talk:Gustav Friedrich Wilhelm Spörer
- Talk:Spörer minimum
- Talk:Spörer's law
- Talk:spray
- Talk:spring equinox -> Talk:vernal equinox
- Talk:Springfield mounting
- Talk:spring tide
- Talk:s-process
- Talk:sputtering
- Talk:Square Kilometre Array
- Talk:Square of Pegasus
- Talk:SS Cygni
- Talk:SS Cygni star
- Talk:SS433
- Talk:S star
- Talk:ST -> Talk:standard time
- Talk:standard atmosphere
- Talk:standard epoch
- Talk:standard solar model
- Talk:standard star
- Talk:standard time
- Talk:standstill
- Talk:star
- Talk:starburst galaxy
- Talk:star cluster
- Talk:star count
- Talk:Stardust
- Talk:Stark broadening
- Talk:starquake
- Talk:starspot
- Talk:star streaming
- Talk:static limit
- Talk:static universe
- Talk:stationary point
- Talk:1
- Talk:2
- Talk:statistical parallax
- Talk:steady-state theory
- Talk:Stefan–Boltzmann constant
- Talk:Stefan–Boltzmann law
- Talk:Stefan's law -> Talk:Stefan–Boltzmann law
- Talk:stellar association
- Talk:stellar atmosphere
- Talk:stellar evolution
- Talk:stellar interferometer
- Talk:stellar population
- Talk:stellar structure
- Talk:stellar wind
- Talk:Stephano (moon)
- Talk:Stephan's Quintet
- Talk:step method -> Talk:Argelander step method -> Talk:Pogson step method
- Talk:steradian
- Talk:STEREO -> Talk:Solar Terrestrial Relations Observatory
- Talk:stereo comparator
- Talk:Steward Observatory
- Talk:stishovite
- Talk:Stokes parameters
- Talk:Stonyhurst heliographic coordinates
- Talk:stony-iron meteorite
- Talk:stony meteorite
- Talk:stratigraphy
- Talk:stratopause
- Talk:stratosphere
- Talk:Stratospheric Observatory for Infrared Astronomy
- Talk:streamer
- Talk:Strehl ratio
- Talk:strewn field
- Talk:1
- Talk:2
- Talk:string -> Talk:cosmic string
- Talk:Bengt Georg Daniel Strömgren
- Talk:Strömgren photometry
- Talk:Strömgren sphere
- Talk:strontium star
- Talk:Struve
- Talk:Friedrich Georg Wilhelm von Struve
- Talk:Otto Struve
- Talk:Otto Wilhelm Struve
- Talk:STScI -> Talk:Space Telescope Science Institute
- Talk:style
- Talk:Subaru Telescope
- Talk:subatomic particle -> Talk:elementary particle
- Talk:subdwarf
- Talk:subgiant
- Talk:subluminous star
- Talk:sublunar point
- Talk:Submillimeter Array
- Talk:Submillimeter Wave Astronomy Satellite
- Talk:submillimetre astronomy
- Talk:sub-pulse
- Talk:subsolar point
- Talk:substellar object
- Talk:substellar point
- Talk:substorm
- Talk:sudden ionospheric disturbance
- Talk:Abd al-Raman al-Sufi
- Talk:Suisei
- Talk:sulcus
- Talk:summer solstice -> Talk:solstice
- Talk:Summer Time
- Talk:Summer Triangle
- Talk:Sun
- Talk:sundial
- Talk:sundog -> Talk:parhelion
- Talk:Sunflower galaxy
- Talk:sungrazer -> Talk:Kreutz sungrazer
- Talk:sunrise
- Talk:sunset
- Talk:sunskirter
- Talk:sunspot
- Talk:sunspot cycle
- Talk:Sunyaev–Zel'dovich effect
- Talk:supercluster
- Talk:supergalactic plane
- Talk:supergiant
- Talk:supergiant elliptical
- Talk:supergranulation
- Talk:superheterodyne receiver
- Talk:superhump -> Talk:SU Ursae Majoris star
- Talk:superior conjunction
- Talk:superior planet
- Talk:superluminal velocity
- Talk:supermassive black hole
- Talk:supermassive star
- Talk:supermaximum -> Talk:SU Ursae Majoris star
- Talk:supernova
- Talk:Supernova 1987A
- Talk:supernova remnant
- Talk:super-rotation
- Talk:super-Schmidt telescope
- Talk:superstring theory
- Talk:supersynthesis
- Talk:surface brightness
- Talk:surface gravity
- Talk:surface temperature
- Talk:surge prominence
- Talk:Surveyor (space probes)
- Talk:SU Ursae Majoris star
- Talk:Suzaku
- Talk:S Vulpeculae star
- Talk:Swan bands
- Talk:Swan Nebula -> Talk:Omega Nebula
- Talk:SWAS -> Talk:Submillimeter Wave Astronomy Satellite
- Talk:Swift (satellite)
- Talk:Comet 109P/Swift–Tuttle
- Talk:Sword Hand of Perseus
- Talk:Sword of Orion
- Talk:SX Arietis star
- Talk:SX Phoenicis star
- Talk:Sycorax (moon)
- Talk:symbiotic star
- Talk:synchronous orbit
- Talk:synchronous rotation
- Talk:syndyname
- Talk:synodic
- Talk:synodic month
- Talk:synodic period
- Talk:Syrtis Major
- Talk:Systems I, II, and III
- Talk:syzygy
T2
edit- Talk:tachocline
- Talk:tachyon
- Talk:TAI -> Talk:Temps Atomique International -> Talk:International Atomic Time
- Talk:cometary tail
- Talk:tangential velocity
- Talk:Tarantula Nebula
- Talk:Tarazed
- Talk:T association
- Talk:Taurid meteors
- Talk:Taurus
- Talk:Taurus A
- Talk:Taurus Molecular Clouds
- Talk:Taurus Moving Cluster
- Talk:Taurus X-1
- Talk:TCB -> Talk:Barycentric Coordinate Time
- Talk:T-class asteroid
- Talk:TDB -> Talk:Temps Dynamique Barycentrique -> Talk:Barycentric Dynamical Time
- Talk:T dwarf
- Talk:Teapot (asterism)
- Talk:Comet Tebbutt (C/1861 J1)
- Talk:technetium star
- Talk:tectonics
- Talk:Teide Observatory
- Talk:tektite
- Talk:telecompressor
- Talk:tele-extender
- Talk:telescope
- Talk:telescope drive -> Talk:drive
- Talk:telescope mounting -> Talk:mounting
- Talk:Telescopio Nazionale Galileo
- Talk:Telescopium (constellation)
- Talk:Telesto
- Talk:telluric lines
- Talk:tellurium
- Talk:Comet 55P/Tempel–Tuttle
- Talk:temperature
- Talk:temperature minimum
- Talk:Tenma
- Talk:termination shock
- Talk:terminator
- Talk:terra
- Talk:terracing
- Talk:terrestrial age
- Talk:Terrestrial Dynamical Time -> Talk:Terrestrial Time
- Talk:terrestrial planet
- Talk:Terrestrial Time
- Talk:tesla
- Talk:tessera
- Talk:Tethys (moon)
- Talk:Thalassa (moon)
- Talk:Thales of Miletus
- Talk:Tharsis Montes
- Talk:Thebe (moon)
- Talk:Themis family
- Talk:Themisto (moon)
- Talk:theory of everything -> Talk:grand unified theory
- Talk:thermal bremsstrahlung -> Talk:free–free transition
- Talk:thermal equilibrium
- Talk:1
- Talk:2
- Talk:thermal radiation
- Talk:thermocouple
- Talk:thermodynamic equilibrium -> Talk:thermal equilibrium
- Talk:thermodynamic temperature
- Talk:thermopile
- Talk:thermosphere
- Talk:thinned chip
- Talk:Third Cambridge Catalogue
- Talk:third contact
- Talk:third quarter -> Talk:last quarter
- Talk:30 Doradus -> Talk:Tarantula Nebula
- Talk:Thirty Meter Telescope
- Talk:tholus
- Talk:William Thomson -> Talk:Lord Kelvin
- Talk:Thomson scattering
- Talk:three-body problem
- Talk:three-colour photography -> Talk:astrophotography
- Talk:three-colour photometry -> Talk:Johnson photometry
- Talk:three-kiloparsec arm
- Talk:Thuban
- Talk:Thule (asteroid)
- Talk:tidal bulge
- Talk:tidal evolution
- Talk:tidal force
- Talk:tidal friction
- Talk:tidal heating
- Talk:tides
- Talk:time
- Talk:time dilation
- Talk:time of perihelion passage
- Talk:time zone
- Talk:TiO bands
- Talk:tip–tilt mirror
- Talk:Tisserand parameter
- Talk:Titan (moon)
- Talk:Titania (moon)
- Talk:Titius–Bode law -> Talk:Bode's law
- Talk:TLP -> Talk:lunar transient phenomenon
- Talk:TMT -> Talk:Thirty Meter Telescope
- Talk:TNG -> Talk:Galileo National Telescope
- Talk:TNO -> Talk:trans-Neptunian object
- Talk:Toby Jug Nebula
- Talk:Tolman test
- Talk:Clyde William Tombaugh
- Talk:topocentric
- Talk:topocentric coordinates
- Talk:Torino scale
- Talk:Toro (asteroid)
- Talk:torquetum
- Talk:torus
- Talk:total eclipse
- Talk:totality
- Talk:total magnitude -> Talk:integrated magnitude
- Talk:total solar irradiance
- Talk:Toutatis (asteroid)
- Talk:TRACE -> Talk:Transition Region and Coronal Explorer
- Talk:train (meteors)
- Talk:transfer function
- Talk:transfer lens
- Talk:transfer orbit
- Talk:transient lunar phenomenon -> Talk:lunar transient phenomenon
- Talk:meridian transit
- Talk:planetary transit
- Talk:transit circle
- Talk:transit instrument
- Talk:transition probability
- Talk:transition region
- Talk:Transition Region and Coronal Explorer
- Talk:transmission grating
- Talk:trans-Neptunian object
- Talk:atmospheric transparency
- Talk:transverse velocity -> Talk:tangential velocity
- Talk:Trapezium (star)
- Talk:Triangulum (constellation)
- Talk:Triangulum Australe (constellation)
- Talk:Triangulum Galaxy
- Talk:Trifid Nebula
- Talk:trigonometric parallax
- Talk:triple-alpha process
- Talk:triplet (lens)
- Talk:triquetrum
- Talk:trischiefspiegler -> Talk:schiefspiegler telescope
- Talk:Triton (moon)
- Talk:Trojan asteroid
- Talk:tropic
- Talk:tropical month
- Talk:tropical period
- Talk:tropical year
- Talk:Tropic of Cancer
- Talk:Tropic of Capricorn
- Talk:tropopause
- Talk:troposphere
- Talk:true anomaly
- Talk:true equator
- Talk:true equinox
- Talk:true pole
- Talk:Trumpler classification
- Talk:Trumpler star
- Talk:TT -> Talk:Terrestrial Time
- Talk:T Tauri star
- Talk:T Tauri wind
- Talk:Tucana (constellation)
- Talk:Tully–Fischer relation
- Talk:Tunguska event
- Talk:tuning-fork diagram
- Talk:atmospheric turbulence
- Talk:turnoff point
- Talk:Nasir al-Din al-Tusi
- Talk:Comet 41P/Tuttle–Giacobini–Kresák
- Talk:21-centimetre line
- Talk:twilight
- Talk:twinkling
- Talk:two-body problem
- Talk:two-colour diagram
- Talk:two-colour photometry -> Talk:BV photometry
- Talk:Two-Micron All-Sky Survey
- Talk:two-spectrum binary -> Talk:composite-spectrum binary
- Talk:Tycho Brahe
- Talk:Tycho Catalogue
- Talk:Tychonic system
- Talk:Tycho's Star
- Talk:Type I supernova -> Talk:supernova
- Talk:Type II supernova -> Talk:supernova
U2
edit- Talk:UBV photometry -> Talk:Johnson photometry
- Talk:UBVRIJKL photometry -> Talk:Johnson photometry
- Talk:U-class asteroid
- Talk:U Geminorum star
- Talk:Uhuru
- Talk:UKIDSS -> Talk:UKIRT Infrared Deep-Sky Survey
- Talk:UKIDSS photometry
- Talk:UKIRT -> Talk:United Kingdom Infrared Telescope
- Talk:UKIRT Infrared Deep-Sky Survey
- Talk:UKST -> Talk:United Kingdom Schmidt Telescope
- Talk:ultra-compact dwarf galaxy
- Talk:ultra-luminous infrared galaxy
- Talk:ultraviolet astronomy
- Talk:ultraviolet excess star
- Talk:ultraviolet photometry
- Talk:ultraviolet radiation
- Talk:Ulugh Beg
- Talk:Ulysses (spacecraft)
- Talk:U magnitude
- Talk:umbra
- Talk:1
- Talk:2
- Talk:Umbriel (moon)
- Talk:undae
- Talk:undersampling
- Talk:Undina family
- Talk:unfilled aperture
- Talk:unit distance
- Talk:United Kingdom Infrared Telescope
- Talk:United Kingdom Schmidt Telescope
- Talk:Universal Time
- Talk:Universe
- Talk:unsharp masking
- Talk:upper culmination -> Talk:culmination
- Talk:Upsilon Sagittarii star
- Talk:Uranometria
- Talk:Uranus
- Talk:Urca process
- Talk:ureilite
- Talk:Harold Clayton Urey
- Talk:Ursa Major
- Talk:Ursa Major Moving Cluster
- Talk:Ursa Minor
- Talk:Ursid meteors
- Talk:US Naval Observatory
- Talk:USNO CCD Astrograph Catalog
- Talk:UT -> Talk:Universal Time
- Talk:UTC -> Talk:Universel Temps Coordonné -> Talk:Coordinated Universal Time
- Talk:Utopia Planitia
- Talk:UU Herculis star
- Talk:UV -> Talk:ultraviolet
- Talk:uvby system -> Talk:Strömgren photometry
- Talk:UV Ceti star
- Talk:UV Persei star
- Talk:UXor -> Talk:UX Orionis star
- Talk:UX Orionis star
- Talk:UX Ursae Majoris star
V2
edit- Talk:vacuum energy
- Talk:Valhalla (impact basin)
- Talk:Valles Marineris
- Talk:vallis
- Talk:James Alfred Van Allen
- Talk:Van Allen Belts
- Talk:Van Biesbroeck's Star
- Talk:Hendrik van de Hulst
- Talk:van Maanen's Star
- Talk:variable star
- Talk:variation
- Talk:1
- Talk:2
- Talk:variation of latitude -> Talk:latitude variation
- Talk:vastitas
- Talk:Vatican Advanced Technology Telescope
- Talk:VBLUW photometry -> Talk:Walraven photometry
- Talk:V-class asteroid
- Talk:Vega (star)
- Talk:Vega probes
- Talk:Veil Nebula
- Talk:Vela (constellation)
- Talk:Vela pulsar
- Talk:Vela Supernova Remnant
- Talk:velocity curve
- Talk:velocity dispersion
- Talk:velocity–distance relation
- Talk:Venera
- Talk:Venus (planet)
- Talk:Venus Express
- Talk:VERITAS -> Talk:Very Energetic Radiation Imaging Telescope Array System
- Talk:vernal equinox
- Talk:vertical circle
- Talk:Very Energetic Radiation Imaging Telescope Array System
- Talk:Very Large Array
- Talk:Very Large Telescope
- Talk:Very Long Baseline Array
- Talk:very long baseline interferometry
- Talk:very slow nova -> Talk:RR Telescopii star
- Talk:Very Small Array
- Talk:Vesta (asteroid)
- Talk:Viking (space probes)
- Talk:VILGEN photometry
- Talk:Vilnius photometry
- Talk:violent relaxation
- Talk:virga
- Talk:Virginid meteors
- Talk:Virgo (constellation)
- Talk:Virgo A
- Talk:Virgo Cluster
- Talk:Virgo Supercluster -> Talk:local supercluster
- Talk:virial theorem
- Talk:Virtual Observatory
- Talk:virtual particle
- Talk:Visible and Infrared Survey Telescope for Astronomy
- Talk:VISTA -> Talk:Visible and Infrared Survey Telescope for Astronomy
- Talk:visual binary
- Talk:visual magnitude
- Talk:VLA -> Talk:Very Large Array
- Talk:VLBA -> Talk:Very Long Baseline Array
- Talk:VLBI -> Talk:very long baseline interferometry
- Talk:VLBI Space Observatory Programme
- Talk:VLT -> Talk:Very Large Telescope
- Talk:V magnitude
- Talk:Hermann Carl Vogt
- Talk:Vogt–Russell theorem
- Talk:void
- Talk:Voigt profile
- Talk:Volans
- Talk:volatile
- Talk:von Zeipel theorem
- Talk:Voyager (space probes)
- Talk:VSOP -> Talk:VLBI Space Observatory Programme
- Talk:Vulcan (hypothetical planet)
- Talk:Vulpecula (constellation)
- Talk:VV Cephei star -> Talk:Zeta Aurigae star
- Talk:VV Sculptoris star
W2
edit- Talk:walled plain
- Talk:Walraven photometry
- Talk:waning
- Talk:Washington Double Star Catalog
- Talk:Water Jar
- Talk:water maser -> Talk:H2O maser
- Talk:water of hydration
- Talk:wavefront
- Talk:waveguide
- Talk:wavelength
- Talk:wavenumber
- Talk:wave plate
- Talk:waxing
- Talk:WC star -> Talk:Wolf–Rayet star
- Talk:WDS -> Talk:Washington Double Star Catalog
- Talk:weber
- Talk:weird terrain
- Talk:Carl Friedrich von Weizsäcker
- Talk:Werner lines
- Talk:Comet West (C/1975 V1)
- Talk:Westerbork Radio Observatory
- Talk:Wezen
- Talk:Fred Lawrence Whipple
- Talk:Whipple Observatory -> Talk:Fred Lawrence Whipple Observatory
- Talk:Whirlpool Galaxy
- Talk:whistler
- Talk:white dwarf
- Talk:white hole
- Talk:white-light corona
- Talk:WHT -> Talk:William Herschel Telescope
- Talk:Wide Field Infrared Survey Explorer
- Talk:Widmanstätten pattern
- Talk:Wielen dip
- Talk:Wien's displacement law
- Talk:Wild Duck Cluster
- Talk:Wild's Triplet
- Talk:Rupert Wildt
- Talk:Wilkinson Microwave Anisotropy Probe
- Talk:William Herschel Telescope
- Talk:Robert Woodrow Wilson
- Talk:Wilson–Bappu effect
- Talk:Wilson effect
- Talk:Comet 107P/Wilson–Harrington
- Talk:WIMP
- Talk:Wind (satellite)
- Talk:winter solstice -> Talk:solstice
- Talk:WISE -> Talk:Wide Field Infrared Survey Explorer
- Talk:WIYN Telescope
- Talk:WMAP -> Talk:Wilkinson Microwave Anisotropy Probe
- Talk:W. M. Keck Observatory
- Talk:WN star -> Talk:Wolf–Rayet star
- Talk:Maximilian ('Max') Franz Joseph Cornelius
- Talk:(Johann) Rudolf Wolf
- Talk:Wolf diagram
- Talk:Wolf–Lundmark–Melotte system
- Talk:Wolf–Rayet star
- Talk:Wolf sunspot number
- Talk:Wolf 359
- Talk:Wollaston prism
- Talk:Wolter telescope
- Talk:Richard van der Riet Woolley
- Talk:world line
- Talk:wormhole
- Talk:Wright telescope
- Talk:wrinkle ridge
- Talk:WR star -> Talk:Wolf–Rayet star
- Talk:W Serpentis star -> Talk:Algol star
- Talk:W Ursae Majoris star
- Talk:W Virginis star
- Talk:Wyoming Infrared Observatory
- Talk:WZ Sagittae star
X2
edit- Talk:XMM-Newton
- Talk:X-ray astronomy
- Talk:X-ray background
- Talk:X-ray binary
- Talk:X-ray bright point -> Talk:coronal bright point
- Talk:X-ray burst
- Talk:X-ray calorimeter
- Talk:X-ray nova
- Talk:X-ray pulsar
- Talk:X-rays
- Talk:X-ray source
- Talk:X-ray telescope
- Talk:X-ray Timing Explorer
- Talk:X-ray transient
- Talk:XTE -> Talk:Rossi X-ray Timing Explorer
- Talk:XUV -> Talk:extreme ultraviolet
Y2
editZ2
edit- Talk:z -> Talk:redshift
- Talk:ZAMS -> Talk:zero-age main sequence
- Talk:Z Andromedae star
- Talk:Zanstra method
- Talk:ZC -> Talk:Zodiacal Catalogue
- Talk:Z Camelopardalis star
- Talk:ZD -> Talk:zenith distance
- Talk:Zeeman effect
- Talk:Zelenchukskaya
- Talk:zenith
- Talk:zenithal attraction
- Talk:zenithal hourly rate
- Talk:zenith distance
- Talk:zenith telescope
- Talk:zero-age horizontal branch
- Talk:zero-age main sequence
- Talk:Zeta Aurigae star
- Talk:ZHR -> Talk:zenithal hourly rate
- Talk:zirconium star -> Talk:S star
- Talk:Z magnitude
- Talk:zodiac
- Talk:Zodiacal Catalogue
- Talk:zodiacal dust
- Talk:zodiacal light
- Talk:Zond
- Talk:zone catalogue
- Talk:zone of avoidance
- Talk:zone time
- Talk:Zubenelgenubi
- Talk:Zürich relative sunspot number -> Talk:relative sunspot number
- Talk:Fritz Zwicky
- Talk:Zwicky Catalogue
- Talk:ZZ Ceti star
Feature entries
edit- Talk:active galactic nucleus
- Talk:Big Bang theory
- Talk:black hole
- Talk:cosmic microwave background
- Talk:cosmology
- Talk:extrasolar planet
- Talk:galaxy evolution
- Talk:gamma-ray burst
- Talk:nova
- Talk:pulsar
- Talk:quasar
- Talk:redshift survey
- Talk:Search for Extraterrestrial Intelligence
- Talk:stellar evolution
- Talk:supernova
- Talk:time
Notes
edit- The list might contain errors
- When you click a red link, please check the spelling of the title before you create the article
- 1, 2 and 3 means that there exist more than one meaning of the term on the previous line
Sources
edit- Ridpath, Ian (2007). Oxford Dictionary of Astronomy. Oxford University Press.