Term Index (C)
- C:
- C band:
- C-BASS: 6 cm survey of the entire sky
- C chondrite:
- C class:
- carbon star (C): star with more carbon than oxygen in its atmosphere
- C*:
- C-band All Sky Survey:
- C-BASS: 6 cm survey of the entire sky
- C-BASS Telescope:
- C-COSMOS:
- C-H:
- methylidyne (CH): compound of one carbon and one hydrogen atom
- C-type shock:
- shock wave: abrupt propagating disturbance in a fluid
- C-type star:
- carbon star (C): star with more carbon than oxygen in its atmosphere
- C. Donald Shane Telescope:
- C/P:
- C20:
- C22:
- C2H2:
- acetylene (C2H2): compound of two carbon and two hydrogen atoms
- C2H4:
- ethylene (C2H4): compound of two carbon and four hydrogen atoms
- C3H4:
- tracer: chemical whose presence indicates the presence of another chemical
- C60:
- CP:
- specific heat: ratio of added temperature to added heat for a material
- CV:
- specific heat: ratio of added temperature to added heat for a material
- C+: ionized carbon missing one electron
- carbon (C): element, C, atomic number 6
- Ca:
- calcium (Ca): element, Ca, atomic number 20
- Ca I:
- calcium (Ca): element, Ca, atomic number 20
- Ca II:
- calcium (Ca): element, Ca, atomic number 20
- Ca II K line:
- cadence: period between observations
- CAESAR: planned space mission to return a sample of a comet
- CAI: calcium/aluminum specs in chondrites
- Calán/Tololo Supernova Search:
- Calán/Tololo Survey: late 1980s to early 1990s search to redshift 0.1
- Calar Alto 2.2 meter telescope:
- Calar Alto 3.5 meter telescope:
- Calar Alto Legacy Integral Field Area Survey:
- CALIFA: spectroscopic map of 600 galaxies
- Calar Alto Observatory:
- calcium (Ca): element, Ca, atomic number 20
- Am star: A-type star with metallic lines
- calcium carbonate:
- calcium silicate:
- calcium-aluminum-rich inclusion:
- CAI: calcium/aluminum specs in chondrites
- calcium-rich gap transient: type of explosive event larger than a nova and smaller than a supernova
- calcium-rich supernova:
- Caldwell:
- Caldwell Catalog: small catalog for amateur astronomers as an adjunct to the Messier Catalog
- Caldwell 12:
- Caldwell 5:
- IC 342: spiral galaxy in the Council of Giants
- Caldwell 79:
- NGC 3201: globular cluster in which a black hole has been identified
- Caldwell Catalog: small catalog for amateur astronomers as an adjunct to the Messier Catalog
- CALIFA: spectroscopic map of 600 galaxies
- California:
- California Extremely Large Telescope (CELT): concept for an extremely large telescope
- California-Kepler Survey (CKS): followup to Kepler to determine stellar radii
- Callisto: well-known Jupiter moon
- Caltech:
- Caltech Infrared Catalog:
- Caltech Submillimeter Observatory (CSO): 10.4 meter submillimeter telescope in Hawaii
- Camargo:
- CAMB:
- CMBFAST: software to calculate CMB anisotropies
- Cambridge Automated Plate Measuring Machine:
- Cambridge Automatic Plate Measuring Machine:
- Cambridge Catalog of Radio Sources (C): series of catalogs of northern hemisphere sources
- Cambridge Interferometer:
- Cambridge OH Suppression Instrument:
- Cambridge Optical Aperture Synthesis Telescope:
- COAST: optical interferometer in England
- Camelopardalis:
- camera:
- GISMO: 2 mm bolometer camera on IRAM 30 m telescope
- MUSTANG: bolometer array on the Green Bank Telescope
- QUEST: sixteen square-degree survey camera
- SCUBA: submillimeter instrument on James Clark Maxwell Telescope
- TolTEC: sensitive infrared camera under construction for the LMT
- cameras:
- CAMISTIC:
- Campo Imperatore:
- Campo Imperatore Near-Earth Object Survey (CINEOS): survey of near-Earth objects
- CAMS:
- ASTRO-H: Japanese space X-ray telescope
- Canada:
- Canada-France Brown Dwarfs Survey:
- CFBDS: survey in search of brown dwarfs
- Canada-France High-z Quasar Survey (CFHQS): 2000s distant quasar survey
- Canada-France Redshift Survey (CFRS): 1990s survey of galaxies to z = 1 to find associations of redshift to characteristics
- Canada-France-Hawaii Telescope (CFHT): 3.6 meter optical/infrared telescope in Hawaii
- Canada-France-Hawaii Telescope Legacy Survey:
- CFHTLS: surveys of transients and stars
- Canadian Cluster Comparison Project (CCCP): multi-wavelength survey of fifty X-ray-selected galaxy clusters
- Canadian Hydrogen Intensity Mapping Experiment (CHIME,CH): radio telescope mapping distant neutral hydrogen
- Canadian Hydrogen Observatory and Radio-transient Detector:
- Canadian Institute for Theoretical Astrophysics (CITA,ICAT): national research organization at University of Toronto
- Canadian Space Agency:
- CSA: includes astronomical research
- CanariCam:
- Canary Islands:
- Canberra Deep Space Communication Complex:
- CANCAM:
- CAESAR: planned space mission to return a sample of a comet
- CANDELS:
- candidate companion (CC): possible object apparently orbiting a known object
- Canes Venatici Cloud:
- Canes Venatici I:
- Canes Venatici II:
- Canis Major:
- Canis Major Dwarf Galaxy: small irregular galaxy in the Local Group
- Canis Major Overdensity:
- canonical pulsar:
- Canopus: second brightest star in the sky
- capacitance:
- dielectric: insulator that responds to an electric field
- capacitor:
- dielectric: insulator that responds to an electric field
- Cape Photographic Durchmusterung:
- CAPMAP: early 2000s array that surveyed CMB polarization
- CAPS:
- Cassini: explorer spacecraft sent to Saturn
- capture theory:
- captured rotation:
- carbide planet:
- carbon planet: theoretical planet type with more carbon than oxygen
- carbon (C): element, C, atomic number 6
- carbon burning: fusion reaction starting with carbon
- magnesium (Mg): element, Mg, atomic number 12
- neon (Ne): element, Ne, atomic number 10
- nucleosynthesis: creation of atomic nuclei
- sodium (Na): metal, Na, atomic number 11
- Carbon CII Line in Post-Reionization and Reionization Epoch:
- CONCERTO: spectrometer aimed at mapping the [CII] line
- carbon cycle:
- carbon dating:
- carbon deflagration:
- carbon detonation:
- carbon dioxide (CO2): compound of carbon atom and two oxygen atoms
- carbon fusion:
- carbon monosulfide:
- tracer: chemical whose presence indicates the presence of another chemical
- carbon monoxide (CO): compound of carbon and oxygen, one atom each
- Carbon Monoxide Mapping Array (COMA): planned experiment to observe epoch of reionization
- Carbon Monoxide Power Spectrum Survey:
- COPSS: survey of CO from star forming epoch
- carbon planet: theoretical planet type with more carbon than oxygen
- carbon star (C): star with more carbon than oxygen in its atmosphere
- carbon to oxygen ratio:
- carbon (C): element, C, atomic number 6
- carbon, nitrogen$#44; oxygen:
- CNO cycle: fusion reaction chain turning hydrogen and nitrogen into helium and nitrogen
- carbon-14:
- carbon-burning shell:
- carbon-enhanced metal.page-poor:
- carbon star (C): star with more carbon than oxygen in its atmosphere
- carbon-oxygen white dwarf:
- white dwarf (WD): stellar remnant of mostly electron degenerate matter
- carbon-rich Wolf-Rayet:
- carbonaceous chondrite (C chondrite): stony meteorites with carbon compounds showing no melting
- carbonate:
- acidity (pH): measure of the activity of hydrogen ions in a solution
- carbonate system: system governing water and CO2 in the presence of each other
- carbonate system: system governing water and CO2 in the presence of each other
- carbonate-silicate cycle: long-term cycle that sequesters Earth carbon
- weathering: changes in surface due to contact with atmosphere
- carbonic acid:
- acidity (pH): measure of the activity of hydrogen ions in a solution
- carbonate system: system governing water and CO2 in the presence of each other
- carbyne:
- methylidyne (CH): compound of one carbon and one hydrogen atom
- Carina:
- Carina-Sagittarius Arm:
- spiral arm: long, winding visible structure within a spiral galaxy
- Carl Sagan Institute (CSI): group researching finding life on other planets and moons
- Carl Sagan Memorial Station:
- Carlsberg Meridian Catalogue (CMC): series of astrometric catalogs from 19th century on
- Carlsberg Meridian Telescope:
- CARMA:
- CARMA EDGE: CO survey of galaxies
- CARMA Extragalactic Database for Galaxy Evolution:
- Carnegie Institute for Science:
- Carnegie Supernova Project (CSP): survey of supernovae lightcurves
- Carrington event: solar storm September 1-3 1859
- Cart du Ciel:
- Cas:
- Cas A:
- CASA: software package for radio interferometry image generation
- Case-Hamburg Survey (LS): 1950s-1970s survey(s) of OB stars
- Cassegrain reflector: reflector telescope with convex secondary mirror
- Cassegrain telescope:
- Cassini: explorer spacecraft sent to Saturn
- radio science: radar and other methods of using radio to probe planets and moons
- Cassini Equinox:
- Cassini: explorer spacecraft sent to Saturn
- Cassini Solstice:
- Cassini: explorer spacecraft sent to Saturn
- Cassini-Huygens:
- Cassini: explorer spacecraft sent to Saturn
- Cassiopeia A: supernova remnant visible for 300 years
- CaSSIS:
- Castro: hydrodynamics simulation software
- casually connection regions:
- inflation: theorized rapid expansion of the very early universe
- CAT:
- cataclysmic variable:
- cataclysmic variable star (CV): star whose magnitude is much brighter on occasion
- Catalina Real-time Transient Survey:
- Catalina Sky Survey (CSS): survey of near-Earth objects
- catalog:
- 87GB Catalog of Radio Sources (87GB): 1980s Green Bank radio survey
- Abell Catalog: galaxy cluster catalog assembled over 1950s-1980s
- Aitken Double Star Catalogue (ADS): 1932 catalog with both multiple-star systems and non-orbiting double stars
- All-Sky Compiled Catalogue (ASCC,ASCC-2.5): 2001 catalog compiled from modern sources
- Arakelian Catalog (Ark): 1970s list of small/bright galaxies
- Arecibo General Catalog (AGC): catalog of galaxies to support ALFALFA surveys
- Arecibo Occultation Survey (AO): 1960s radio survey using occultations by the Moon
- Arp-Madore Catalog of Southern Peculiar Galaxies (AM): 1970s-1980s catalog from the UK Schmidt Survey
- Asiago Supernova Catalog (B/SN): 1999 catalog of known supernovae and their galaxies
- Astrographic Catalog (AC): historical star catalog of the whole sky to magnitude 11
- astronomical catalog: lists of observed astronomical bodies and their characteristics
- Astronomische Gesellschaft Katalog (AGK): 19th/20th century astrometric catalog
- Atlas of Galactic Nebulae (GN): 1980s catalog of Milky-Way nebulae
- Atlas of Peculiar Galaxies (APG): 1960s catalog-book with photos
- ATNF Pulsar Catalogue: online catalog of pulsars
- Barnard Catalog (Barnard,B): 1919 catalog of dark nebulae
- Basel Open Cluster Catalogue (Basel): list of open clusters
- Becker, White, and Edwards Catalog (BWE): 1990s radio catalog from a Green Bank 300ft Telescope survey
- Berkeley Open Cluster Catalogue (Be): list of open clusters
- Bibliographic Catalog of Variable Stars (BCVS): listing of references to variable stars
- Bonner Durchmusterung Catalog (BD): well-known astrometric catalog from late 1800s
- Boss General Catalog (GC): 1937 catalog of 30,000 stars
- Bright Star Catalog (HR,BS,YBS): early 20th century catalog of 9000 stars
- Burnham Double Star Catalogue (BDS,BU): 1906 catalog with multiple star systems and non-orbiting double stars
- Caldwell Catalog: small catalog for amateur astronomers as an adjunct to the Messier Catalog
- Cambridge Catalog of Radio Sources (C): series of catalogs of northern hemisphere sources
- Carlsberg Meridian Catalogue (CMC): series of astrometric catalogs from 19th century on
- Catalog of Azzopardi & Vigneau (AzV): probable stars in the SMC
- Catalog of Circumpolar Stars (Groombridge): list of over 4000 stars in northern part of the sky
- Catalog of Components of Double and Multiple Stars (CCDM): 1994 catalog of 74000 such double-star components
- Catalog of Galaxies and Clusters of Galaxies (CGCG): list of galaxies/clusters assembled in 1960s
- Catalog of Infrared Observations (CIO): collection of infrared observation data from numerous sources
- Catalog of Stellar Identifications (CSI): 1970s catalog cross referencing existing star catalogs
- Catalogue of Cometary Orbits (CCO): comet catalog updated since 1970s
- Catalogue of Galactic Planetary Nebulae (PK,PK67): 1967 catalog
- Catalogue of Interacting Galaxies (VV): begun in the 1950s
- Catalogue of Southern Double Stars: 1955 catalog with multiple star systems and non-orbiting double stars
- Catalogues of Fundamental Stars: series of astrometric catalogs from 19th century on
- Cederblad Catalog (Ced): list of bright nebulae
- Collinder Catalog (Cr): 1930s catalog of 471 open clusters
- Cosmic Lens All-sky Survey (CLASS): radio survey aimed at gravitational lenses
- CRATES: catalog of 8.4 GHz data on radio sources
- Czernik Catalog (Cz): list of open clusters
- David Dunlap Observatory Catalog (DDO): catalog of dwarf galaxies
- Dickel-Wendker-Bieritz Catalog (DWB): list of HII regions in the Cygnus X star forming region
- Dolidze-Dzimselejsvili Catalogue (DoDz): list of 11 open clusters
- Dunlop Double Star Catalogue (DUN): 1829 catalog of double stars viewed from Australia
- Duus-Newell catalog (DN): list of southern galaxies/clusters assembled in 1970s
- ESO/Uppsala Survey of the ESO (B) Atlas: 1970s southern all-sky survey
- Fairall Galaxy List (Frl,Fairall): 1977 list of galaxies with bright nuclei
- Fourth Cambridge Catalog of Radio Sources (4C): 1960s catalog of northern hemisphere 178 MHz sources
- Frank Ross's Catalog (Ross): high-proper-motion and variable stars catalogued by Frank Ross
- Galactic O Star Catalog (GOSC,GOS): 2000s catalog of O-type stars
- General Catalog of Trigonometric Parallaxes (GCTP): 1950s star catalog with later updates
- General Catalogue of Stellar Radial Velocities (GCRV): 1950s century catalog of 1500 stars with radial velocities
- General Catalogue of Trigonometric Parallaxes (GCTP): 1950s catalog of stars with parallax measures
- General Catalogue of Variable Stars (GCVS): 20th/21st century catalog of 58000 variable stars
- Gliese Catalogue of Nearby Stars (Gl,Gliese): 1950s catalog of stars within 20 parsecs
- Gliese-Jahreiss Catalog (GJ): 1991 catalog of stars within 25 parsecs
- Green Bank 6-cm Radio Source Catalog (GB6): catalog of from 1980s northern-hemisphere radio survey
- Guide Star Catalog (GSC,HSTGC): catalog of stars to help aim HST
- Henry Draper Catalog (HD): early 20th century spectroscopic catalog of stars
- Herschel Double Star Catalog (H): series of early double star catalogs
- Herz catalog (Herz): list of 3000 stars in a strip of the southern sky
- Index Catalog (IC): 1895 catalog of galaxies, star clusters, and other nebulae
- ITEP-SAI Supernova Light Curve Catalogue: online catalog
- King Catalog: list of 21 open clusters
- Lépine Shara Proper Motion catalog (LSPM): 2000s catalog of stars with proper motion
- Lacaille Star Catalog (Lac): 1700s catalog of about 10,000 southern hemisphere stars
- Lowell Proper Motion Survey (G): 1950s-1970s catalogs of stars with proper motion
- Luyten Double Star Survey (LDS): 1940s-1970s catalog of double stars
- Luyten Half-second Catalog (LHS): 1979 catalog of 4000 stars with high proper motion
- Luyten Palomar Survey (LP): 1960s catalog of stars with high proper motion
- Luyten Two-Tenths Arcsecond Catalog (LTT): 1960 catalog of 9000+ stars with proper motion
- Lynds Catalog of Dark Nebulae (LDN,L): 1950s/1960s list of dark nebulae found on Palomar plates
- Lynds Catalogue of Bright Nebulae (LBN): 1950s/1960s list of bright nebulae found on Palomar plates
- MASH Catalog of Planetary Nebulae: 995 possible planetary nebulae
- Max Wolf's catalog of stars with proper motion: early 20th century catalog of 1500 stars
- Melotte Catalog: 1915 catalog of open and globular clusters
- Messier Catalog (M): catalog of astronomical objects to avoid when looking for comets
- MIT X-ray Burst Source Catalog (MXB): 1970s catalog of X-ray bursters
- Morphological Catalogue of Galaxies (MCG): 1960s catalog from Palomar plates
- MSH Catalog (MSH): 1950s catalog of radio sources from a Mills Cross survey
- N30 Catalog: 1950s catalog collecting proper motion data from older catalogs
- New Catalogue of Suspected Variable Stars (NSV): catalog from latter half of 20th century catalog
- New General Catalogue (NGC): 1888 catalog of galaxies, star clusters, and other nebulae
- NOMAD: astrometric star catalog
- Ohio Radio Survey (OSS): 1960s radio survey by Ohio State University
- Open Exoplanet Catalogue (OEC): independently maintained list of known exoplanets
- Palomar Globular Clusters (Pal): list of 15 globular clusters found in POSS plates
- Palomar-Haro-Luyten Catalog (PHL): 1960s catalog of faint blue stars
- Pantheon: catalog of well-checked Type Ia supernovae
- Parkes Catalog (PKS): catalog of from 1960s-1990 of radio sources in southern hemisphere
- Parsamian Nebula Catalog: 1965 list of nebulae
- Polar-ring Catalog (PRC): 1990 catalog of polar-ring galaxies
- PPM Star Catalogue: 1991 astrometric catalog with proper motions
- Principal Galaxies Catalog (PGC): modern catalog of more than 70k galaxies
- Radcliffe Observatory Magellanic Clouds Catalogue (RMC): catalog of stars in
- RASS/Green Bank Catalog (RGB,RASSGB): combined list of radio galaxies from Rosat and Green Bank surveys
- Reference Catalogue of Bright Galaxies (RC,RC1): series of catalogs of nearby galaxies
- Roma-BZCAT: 2008 catalog of blazars
- SAO Star Catalog: 1960s catalog
- Shapley-Ames Catalog (SAC): 1932 catalog of contemporary data on 1249 galaxies
- Sharpless Catalog (Sh2): catalog of HII regions found on Palomar plates
- Spectroscopic Properties of Cool Stars (SPOCS): analysis of spectroscopic data of 7000+ M and L stars
- Strasbourg-ESO Catalog of Galactic Planetary Nebulae (PNG): 1992 catalog of 1820 objects
- Struve Catalogs: two catalogs of double stars
- Texas Survey of Radio Sources at 365 MHz (TXS): 1970s/1970s radio survey made with the Texas Interferometer
- Third Cambridge Catalogue of Radio Sources (3C): 1959 catalog of northern hemisphere 159MHz sources
- Transient Name Server (TNS): online catalog of transients
- Uppsala General Catalogue (UGC): 1973 catalog of galaxies visible from northern hemisphere
- USNO CCD Astrograph Catalog (UCAC): USNO star catalog including proper motions
- USS Sources: catalog of sources with steep spectral index
- Van Den Bergh Reflection Nebula Catalog (vdB): catalog of reflection nebulae found in POSS plates
- Villanova White Dwarf Catalog: ongoing catalog of white dwarfs
- Virgo Cluster Catalog (VCC): 1980s catalog of 2000 galaxies
- Washington Double Star Catalog (WDS): modern database of double stars
- WISeREP: interactive catalog of supernovae
- Catalog of 5,268 Standard Stars, 1950.0 Based on the Normal System N30:
- N30 Catalog: 1950s catalog collecting proper motion data from older catalogs
- Catalog of Azzopardi & Vigneau (AzV): probable stars in the SMC
- Catalog of Circumpolar Stars (Groombridge): list of over 4000 stars in northern part of the sky
- Catalog of Components of Double and Multiple Stars (CCDM): 1994 catalog of 74000 such double-star components
- Catalog of Dark Nebulae:
- Catalog of Galaxies and Clusters of Galaxies (CGCG): list of galaxies/clusters assembled in 1960s
- Catalog of Infrared Observations (CIO): collection of infrared observation data from numerous sources
- Catalog of Nearby Stars:
- Catalog of Stellar Identifications (CSI): 1970s catalog cross referencing existing star catalogs
- catalog-based designator:
- catalogs:
- Astrocats: software to create and manage an astronomy catalog
- astronomical catalog: lists of observed astronomical bodies and their characteristics
- catalogue:
- Catalogue des Nebuleuses et des Amas d'Etoiles:
- Messier Catalog (M): catalog of astronomical objects to avoid when looking for comets
- Catalogue of Bright Nebulae:
- Catalogue of Cometary Nebulae Discovered on Palomar Maps:
- Catalogue of Cometary Orbits (CCO): comet catalog updated since 1970s
- Catalogue of Galactic Planetary Nebulae (PK,PK67): 1967 catalog
- Catalogue of Interacting Galaxies (VV): begun in the 1950s
- Catalogue of Nearby Stars:
- Catalogue of Nebulae and Clusters of Stars:
- Catalogue of Nebulae and Star Clusters:
- Messier Catalog (M): catalog of astronomical objects to avoid when looking for comets
- nebula: cloud of dust and gas
- Catalogue of Rich Clusters of Galaxies:
- Catalogue of Southern Double Stars: 1955 catalog with multiple star systems and non-orbiting double stars
- Catalogues of Fundamental Stars: series of astrometric catalogs from 19th century on
- Catalogus Britannicus:
- cation:
- ion: non-neutral atom or molecule, with missing or extra electrons
- CATS345:
- Cauchy distribution:
- caustic structure:
- core-cusp problem: theories and observation show different dwarf galaxy rotation curves
- cavity-enhanced absorption spectroscopy (CEAS): passing a beam through a gas multiple times to amplify absorption lines
- CB:
- CBB:
- CBI:
- CBR:
- CC:
- CCAT: 25-meter submillimeter telescope plan for Chile
- CCAT-p:
- CCAT-prime:
- CCCP:
- CCCS:
- CCD: electronic device to detect light
- CCD photometry:
- photometry: studying starlight through bandpass filters
- CCDM:
- CCDs:
- CCO:
- CCS:
- CCSN:
- CCSN progenitor:
- cD:
- cD galaxy:
- CDA:
- Cassini: explorer spacecraft sent to Saturn
- CDF-N:
- CDF-North:
- CDF-S:
- CDF-South:
- CDFN:
- CDFS:
- CDISORT:
- DISORT: simulation of radiative transfer in an atmosphere
- CDM:
- CDPP:
- CDS:
- CDSCC:
- CE:
- CE1:
- CE2:
- CEA:
- CEA SAp:
- CEA Service d'Astrophysique (CEA SAp): French national astrophysics research institute
- CEAS:
- CEB:
- CEBE:
- Ced:
- Cederblad:
- Cederblad Catalog (Ced): list of bright nebulae
- CEDUNA:
- CEL:
- celestial body:
- celestial coordinate system: system for specifying position of celestial objects
- celestial coordinates:
- celestial equator: equator-like line around the celestial sphere
- celestial event: generally something happening visible in the sky
- celestial mechanics: study of forces and motion of celestial objects
- celestial meridian: celestial sphere's meridian passing overhead
- meridian: circle around the Earth passing through both poles
- transit: a celestial body passing between another and an observer
- celestial north pole:
- celestial object:
- celestial pole: point within the celestial sphere aligned with Earth's rotation axis
- celestial south pole:
- celestial sphere: the sky in considered as a sphere surrounding the observer
- CELIAS:
- cell:
- Hadley cell: circulation pattern of up at the equator, poleward, down, and back
- zonal flow: east-west air circulation
- zone: apparent "horizontal" band in an atmosphere
- Celsius:
- kelvin (K): temperature scale starting at absolute zero
- CELT:
- CEMP:
- carbon star (C): star with more carbon than oxygen in its atmosphere
- CEMP-no:
- carbon star (C): star with more carbon than oxygen in its atmosphere
- CEMP-r:
- carbon star (C): star with more carbon than oxygen in its atmosphere
- CEMP-r/s:
- carbon star (C): star with more carbon than oxygen in its atmosphere
- CEMP-s:
- carbon star (C): star with more carbon than oxygen in its atmosphere
- centaur: asteroid-like body orbiting among the outer planets
- Centaur rocket stage:
- LCROSS: space probe observing the lunar poles
- centaurs:
- minor planet: lesser solar system body without comet characteristics
- Centaurus:
- Centaurus A:
- Center for Astronomy of Heidelberg University:
- Center for Astrophysics (CfA): Harvard and Smithsonian research and education organization
- Center for Astrophysics Redshift Survey:
- Center for High Angular Resolution Astronomy:
- CHARA: optical interferometer
- center of gravity:
- center of mass:
- barycenter: center of mass of two orbiting bodies
- reduced mass: the reciprocal of the sum of the reciprocals of the masses of two objects
- center of mass frame of reference:
- center of the Milky Way:
- centigrade:
- kelvin (K): temperature scale starting at absolute zero
- centimeter size barrier:
- barrier: challenging issue regarding planet formation
- centimeter-gram-second system:
- CGS: metric system variant
- centimeter-wave astronomy:
- central body:
- primary: central body of a system such as the Sun in the solar system
- central compact object:
- compact object (CO): dense astronomical body such as white dwarf or denser
- central limit theorem:
- central peak:
- central star of the planetary nebula:
- Centre de données astronomiques de Strasbourg (CDS): repository of astronomical data
- SIMBAD: online database of astronomical objects
- Centre national d'ètudes spatiales (CNES): French space agency
- CEP:
- Cepheid:
- Cepheid variable (CEP): type of star that varies with a constant period
- Ceres: dwarf planet and largest asteroid
- asteroid: minor planet without comet characteristics
- Dawn: explorer spacecraft sent to asteroids Vesta and Ceres
- dwarf planet: round like a planet, only smaller
- facula: bright spot on a planet or the Sun
- planet: round object orbiting a star that clears out its own orbital path
- protoplanet: simplest, least-developed object classified as a planet
- Titius-Bode law: relationship between the distances between solar system planets
- Cerro Armazones Observatory:
- Cerro Chajnantor:
- Cerro Chajnantor Atacama Telescope:
- CCAT: 25-meter submillimeter telescope plan for Chile
- Cerro Chajnantor Atacama Telescope, prime:
- Cerro Pachón:
- Cerro Paranal:
- Cerro Toco:
- Cerro Tololo:
- Cerro Tololo Inter-American Observatory (CTIO): NOAO observatory in Chile with Blanco telescope
- CERTO:
- ARGOS: 1999 technology-research satellite
- CES:
- CfA:
- CfA Redshift Survey: 1970s-1990s surveys of galaxy redshifts
- CfA1 Survey:
- CfA2 Great Wall:
- CfA2 Survey:
- CFBD:
- CFBDS: survey in search of brown dwarfs
- CFBDS: survey in search of brown dwarfs
- CFBDSIR:
- CFBDS: survey in search of brown dwarfs
- CFD:
- CFH12k:
- CFHQS:
- CFHT:
- CFHTLS: surveys of transients and stars
- CFL condition:
- CFRS:
- CFS:
- CFT:
- CG:
- CGB:
- CGCG:
- CGCS:
- CGI:
- CGM:
- CGO:
- CGRO:
- CGS: metric system variant
- erg: CGS unit of energy
- gauss (G,Gs): measurement of magnetic field β
- magnetic flux (Φ): total magnetism passing through a surface
- magnetic flux density (B): vector field describing magnetism in relation to the Lorentz force
- SI: modern metric system
- CGS4:
- CGSS:
- CH:
- CH star:
- CH3D:
- methane (CH4): compound of one carbon and 4 hydrogen atoms
- CH4:
- methane (CH4): compound of one carbon and 4 hydrogen atoms
- Chabrier IMF:
- CHAI:
- Chajnantor Observatory:
- Chajnantor Plateau:
- Challenger:
- SPARTAN: series of astronomy satellites launched/retrieved by space shuttle
- Chandler Wobble:
- Chandra:
- Chandra Carina Complex Project:
- Chandra COSMOS Survey:
- Chandra Deep Field North (CDFN,CDF-N): X-ray deep survey encompassing HDF region
- Chandra Deep Field South (CDFS,CDF-S): X-ray deep survey encompassing HDF-South region
- Chandra Deep Fields:
- Chandra X-ray Observatory (CXO): space X-ray telescope
- ACIS: imaging spectrometer on Chandra X-ray telescope
- Chandrasekhar friction:
- Chandrasekhar limit: maximum mass of a white dwarf
- ChaNGa:
- chaos:
- Lyapunov time: timescale over which a dynamical system is chaotic
- chaos theory: theory of systems highly sensitive to initial conditions
- CHARA: optical interferometer
- characteristic age:
- characteristic magnetic field:
- characteristic strain:
- Characterizing Exoplanet Satellite:
- CHEOPS: space telescope in development to measure radii of exoplanets
- charge:
- charge barrier:
- barrier: challenging issue regarding planet formation
- electrostatic barrier: the problem that dust grains will repel and not join to form planet seeds
- charge exchange:
- charge-coupled device:
- CCD: electronic device to detect light
- quantum efficiency (QE): measure of instrument's ability to sense EMR
- charged black hole:
- charged particles:
- Chariklo:
- CHARIS:
- charm quark:
- particle: very small thing
- quark: type of elementary particle incorporated in protons and neutrons
- standard model: model of elementary particles including quarks
- Charon:
- Earth: third solar system planet from the Sun
- Haumea: dwarf planet discovered in 2004
- moon: a planet's natural satellite, such as Earth's
- Pluto: dwarf planet formerly listed as one of the nine planets
- synchronous orbit: orbit with angular velocity matching the rotation of the orbited body
- CHE:
- ChemCam:
- chemical composition:
- abundances: relative amounts of each chemical element
- chemical composition of the universe:
- abundances: relative amounts of each chemical element
- chemical differentiation:
- chemical element:
- element: class of atom based on its number of protons
- chemical equilibrium (CE): state where chemical makeup is unchanging
- chemical evolution:
- abundances: relative amounts of each chemical element
- chemical kinetics:
- chemical species:
- chemically peculiar:
- chemically peculiar star (CP star): star with SED showing presence metals unusual for stars
- chemisorption:
- chemistry:
- abiotic oxygen: oxygen from non-life sources
- abundances: relative amounts of each chemical element
- acetylene (C2H2): compound of two carbon and two hydrogen atoms
- acidity (pH): measure of the activity of hydrogen ions in a solution
- adsorption: adhesion to a surface
- amine: type of compound containing nitrogen
- ammonia (NH3): particular compound of nitrogen and hydrogen
- atomic number (Z): number of protons in an atomic nucleus
- Avogadro's number (NA): roughly number of hydrogen atoms in a gram
- bulk density: total mass divided by total volume
- calcium (Ca): element, Ca, atomic number 20
- carbon (C): element, C, atomic number 6
- carbon dioxide (CO2): compound of carbon atom and two oxygen atoms
- carbon monoxide (CO): compound of carbon and oxygen, one atom each
- carbonate system: system governing water and CO2 in the presence of each other
- carbonate-silicate cycle: long-term cycle that sequesters Earth carbon
- chemical equilibrium (CE): state where chemical makeup is unchanging
- chemodynamics: study of the dynamics of chemical reactions
- clathrate: crystal lattice with voids that can trap molecules
- diffusion: the spreading of particles toward an even distribution
- electron shell: radius-level around an atomic nucleus at which electrons can orbit
- element: class of atom based on its number of protons
- energetic neutral atom (ENA): high-speed neutral atom
- equilibrium condensation model: chemical model explaining solar system planet abundances
- ethylene (C2H4): compound of two carbon and four hydrogen atoms
- fractionation: separation of compounds from a mixture
- fractionation factor: isotope quantity
- geochemistry: the chemistry of the Earth, planets, and moons
- glycine (Gly,G): smallest of the twenty common amino acids
- helium (He): non-metallic element, He, atomic number 2
- hydrocarbon (HC): any compound of just carbon and hydrogen
- hydrogen (H): most prominent element, atomic number 1
- hydrogen deuteride (HD): hydrogen molecule with one deuterium atom
- hydroxyl (OH): neutral compound of hydrogen and oxygen, one atom each
- ice: solid state of water
- iron (Fe): metal, Fe, atomic number 26
- lithium (Li): metal, Li, atomic number 3
- magnesium (Mg): element, Mg, atomic number 12
- metallic hydrogen: a high-pressure state of hydrogen that is conductive
- methane (CH4): compound of one carbon and 4 hydrogen atoms
- methylidyne (CH): compound of one carbon and one hydrogen atom
- Milky Way chemical evolution: process of the development of metals in the Milky Way
- mole (mol): unit roughly the count of hydrogen atoms in a gram
- molecular handedness: mirror-imaged variants of some molecules
- neon (Ne): element, Ne, atomic number 10
- nickel (Ni): metal, Ni, atomic number 28
- nitrite (NO2-): ion of a nitrogen atom and two oxygen atoms with extra electron
- nitrogen (N): metal, N, atomic number 7
- number density (n): number of objects per volume
- oxidation state: number of electrons loaned out by an atom in an ionic bond
- oxygen (O): element, O, atomic number 8
- PAH emissions: infrared emission from polycyclic aromatic hydrocarbons in gas clouds
- particle number (N): number of particles
- photochemistry: study of the chemical effects of light
- photodissociation: chemical reaction in which photons break chemical bonds
- polycyclic aromatic hydrocarbon (PAH): hydrocarbons consisting of meshes of benzene rings
- potassium/thorium ratio (K/Th ratio): indication of thermal history
- radiolysis: similar to photodissociation from higher energy photons
- reducing atmosphere: atmosphere lacking oxygen or other oxidizers
- reduction potential (Eh,ORP,pE): measure of a chemical species' tendency to acquire electrons
- refractory material: material with high condensation temperature
- relativistic effect: a substantial fraction of the speed of light
- siderophile: material that dissolves in molten iron
- signatures of formation: qualities of a body that suggest how it was formed
- silicate: type of compound including silicon and oxygen
- silicate weathering feedback: feedback mechanism stabilizing carbon in Earth atmosphere
- silicon (Si): metal, Si, atomic number 14
- sodium (Na): metal, Na, atomic number 11
- SPECTRE: an interactive spectrum analysis software package
- stellar population: grouping of stars according to metallicity
- sulfur (S): metal, S, atomic number 16
- surface reaction: such as reactions between gas and adjacent liquid
- titration: analyzing a chemical solution by color change
- volatile material: material with low condensation temperature
- water activity (aw): measure of partial vapor pressure of water
- chemodynamics: study of the dynamics of chemical reactions
- CHEOPS: space telescope in development to measure radii of exoplanets
- Cherenkov cone:
- Cherenkov detector: type of high energy photon or particle detector
- Cherenkov gamma-ray telescope:
- Cherenkov radiation: radiation from the shock of a charged particle passing through a medium
- Cherenkov telescope:
- Cherenkov Telescope Array (CTA): ground gamma-ray telescope array in development
- Chereul:
- Chern-Simons general relativity:
- Chern-Simons gravity: one type of modified general relativity
- Chern-Simons modified general relativity:
- Chern-Simons theory:
- Chi Draconis A:
- F-type star (F): spectral class of star a bit hotter than then Sun
- chi-squared:
- chi-squared test (χ² test): statistical significance test
- Chile:
- CHIME:
- CHIMERA:
- China:
- ARGO-YBJ Experiment: cosmic-ray/gamma-ray detector in Tibet
- FAST: Arecibo-like 500 m telescope in deployment in China
- LAMOST: Chinese telescope for spectroscopic surveys of stars and galaxies
- Tianwen-1 (TW-1): Mars rover launched in July 2020 and on its way
- CHIP:
- CHIPSat: small satellite to investigate ISM plasma
- chiral EFT:
- chirality:
- chirp: burst of signal rising or falling in frequency
- chirp mass (Mc,ℳ): a reduced-mass-like quantity that relates to gravitational waves
- chloride:
- geochemistry: the chemistry of the Earth, planets, and moons
- chlorine:
- geochemistry: the chemistry of the Earth, planets, and moons
- chondrite: stony meteorites showing no melting
- chondrule:
- CAI: calcium/aluminum specs in chondrites
- chondrite: stony meteorites showing no melting
- chopper:
- chopping mirror: internal pivoting mirror to slightly change the instrument's aim
- chopping:
- chopping mirror: internal pivoting mirror to slightly change the instrument's aim
- chopping mirror: internal pivoting mirror to slightly change the instrument's aim
- CHORD:
- Christie:
- ChroMag:
- chromatic aberration: focusing different wavelengths differently
- chromatic dispersion:
- chromium:
- chromosphere: middle layer of the Sun's atmosphere
- chromospheric activity index: measure of magnetic activity of a star's chromosphere
- Chthonian:
- Chthonian planet:
- Chupina:
- CHZ:
- CI:
- CIAO:
- CIB:
- CIBR:
- CID:
- CIDA:
- Stardust: space mission that collected and returned comet coma dust
- CIG: initiative to produce Earth-science software
- Cigar Galaxy:
- M82: nearby starburst galaxy
- CII:
- CIII:
- Cimolai:
- CINEOS:
- CIO:
- CIRCE:
- Circinus Galaxy (ESO 97-G13): nearest Seyfert galaxy
- circle:
- conic section: orbit shapes, like the intersection of a plane and cone
- circle of latitude: circle around the Earth of points equidistant from a pole or the equator
- circular polarization:
- circular polarization radar:
- circular polarization ratio (CPR): ratio of circular polarization handedness in reflected radar signal
- circumbinary planet: exoplanet orbiting two stars
- circumgalactic medium (CGM): gas surrounding a galaxy
- circumplanetary disk: disk of dust and gas around a planet
- circumstellar disk: disk or ring shaped accumulation of matter around a star
- disk: rotating disk-shaped object such as disk galaxy or circumstellar disk
- circumstellar envelope:
- circumstellar habitable zone:
- circumstellar material:
- cirrus:
- cirrus cloud:
- CIRS:
- CISCO:
- CITA:
- CIV:
- ARGOS: 1999 technology-research satellite
- CIVA:
- Rosetta: space probe that visited a comet
- CKM Matrix:
- quantum mixing: means by which one particle spontaneously changes to another
- CKM Mixing:
- quantum mixing: means by which one particle spontaneously changes to another
- CKS:
- CKS-COOL:
- Cl:
- CLAES:
- CLASS:
- Class 0 YSO:
- Class I YSO:
- Class II YSO:
- Class III YSO:
- classical Cepheid:
- classical gravitational field:
- classical KBO:
- Kuiper Belt (K Belt,KB): further part of solar system beyond Neptune
- classical Kuiper Belt object:
- Kuiper Belt (K Belt,KB): further part of solar system beyond Neptune
- classical Lyot coronagraph:
- classical mechanics:
- classical nova:
- nova (N): white dwarf explosion
- classical T-Tauri star:
- classification:
- clathrate: crystal lattice with voids that can trap molecules
- clathrate hydrate:
- clathrate: crystal lattice with voids that can trap molecules
- Clay Telescope:
- CLC:
- CLEAN: algorithm to extract usable images from interferometry-produced images
- CASA: software package for radio interferometry image generation
- dirty image: image that includes the distortions of the beam and sampling
- clean image:
- CLEAN: algorithm to extract usable images from interferometry-produced images
- dirty image: image that includes the distortions of the beam and sampling
- clearing the neighborhood:
- dwarf planet: round like a planet, only smaller
- planet: round object orbiting a star that clears out its own orbital path
- CLF:
- climate:
- climate change:
- earthshine: reflected and emitted electromagnetic radiation from Earth
- climate model:
- Clio2:
- MMT: 6.5 meter telescope at Mt. Hopkins, Arizona
- close binary:
- close binary star:
- closed magnetic field lines:
- closed universe:
- closure phase:
- speckle masking: speckle suppression technique using a calculation of the bispectrum
- cloud: higher-density region of space
- cloud droplet:
- cloud fragmentation: clumping in clouds due to gravitational instability
- cloud mass function:
- cloud of galaxies:
- cloud type:
- clouds:
- Cloudy: code to model the effect of gas and plasma on spectra
- clump:
- clump giant:
- red clump (RC): like horizontal branch but at one temperature
- clump mass function:
- CLUPI:
- CLUST:
- cluster:
- galaxy cluster (CL): large group of galaxies gravitationally-bound to the group
- cluster dark matter halo:
- cluster environment:
- cluster fitting:
- cluster radius: radius of a galaxy cluster
- CM:
- CMA:
- CMa Dwarf:
- CMa Overdensity:
- CMB:
- CMB anisotropies: variations in the spectrum of the CMB
- CMB cold spot:
- CMB dipole:
- CMB foreground:
- CMB halo weak lensing:
- weak lensing (WL): slight lensing detected in random patterns of distant objects
- CMB lensing: gravitational lensing of the CMB
- CMB polarization: effects of scattering and lensing on the CMB
- CMB Stage-4 (CMB-S4): planned 2020s-generation of ground CMB observations
- CMB-S4:
- CMB Stage-4 (CMB-S4): planned 2020s-generation of ground CMB observations
- CMBFAST: software to calculate CMB anisotropies
- CMBR:
- CMC:
- CMD:
- CMDM:
- MMX: Japanese probe to bring back a sample of a Martian moon
- CME:
- CMF:
- CMFGEN: RT code designed to handle significant stellar wind
- Cn:
- CN Leonis:
- CNB:
- CNES:
- CNM:
- CNN:
- CNO:
- CNO cycle: fusion reaction chain turning hydrogen and nitrogen into helium and nitrogen
- CNO cycle: fusion reaction chain turning hydrogen and nitrogen into helium and nitrogen
- oxygen (O): element, O, atomic number 8
- CNRS:
- CO:
- CO ice line:
- snow line: distance from protostar cool enough for water to condense
- CO J ladder:
- CO ladder:
- CO Legacy Database for GASS:
- COLD GASS: survey of CO in nearby large galaxies
- CO Mapping Array Pathfinder:
- COMAP: high frequency radio telescope to map CO
- CO rotational ladder:
- CO to H2 factor (Xco,XCO): assumed ratio between observed CO emission lines and H2 mass
- CO2:
- CO2 ice line:
- snow line: distance from protostar cool enough for water to condense
- COAST: optical interferometer in England
- coastal Kelvin wave:
- Kelvin waves: pressure and gravity waves formed by Coriolis force and a barrier
- COB:
- COBE:
- CoD:
- code: astrophysical modeling computer program
- AREPO: cosmology simulation using moving mesh technique
- AstroBEAR: MHD simulation system
- Athena: MHD code
- ATLAS Stellar Model: computer model of a stellar photosphere
- BPASS: evolution and population synthesis code for binary stars
- BT-Settl: model atmosphere of small stars and brown dwarfs
- Castro: hydrodynamics simulation software
- Cloudy: code to model the effect of gas and plasma on spectra
- CMFGEN: RT code designed to handle significant stellar wind
- COMPAS: SPS code for compact object binaries
- DISORT: simulation of radiative transfer in an atmosphere
- DustEM: code to calculate dust extinction and emission
- Enzo: hydrodynamic simulation system
- FLASH: hydrodynamic simulation system
- FORNAX: hydrodynamics simulation software
- GR1D: core collapse supernova simulation in 1D with GR
- Hyperion: Monte Carlo radiative transfer code
- iSALE: code modeling the shock physics of impacts
- MagIC: numerical code to for fluid dynamics including dynamos
- mlmapper: software for maximum-likelihood mapmaking
- NBODY: code to carry out N-body simulations
- PHOENIX stellar model: computer model of a stellar photosphere
- PLUTO Code: fluid-dynamic simulation code
- PROMETHEUS/VERTEX: hydrodynamic simulation system
- RAMSES: hydrodynamic simulation system
- RODEO: code for 2D disk simulation
- SpEC: code to solve general relativity problems
- StarTrack: stellar population synthesis code
- Turtlebeach: radiative transfer code
- Code for Anisotropies in the Microwave Background:
- CMBFAST: software to calculate CMB anisotropies
- code type:
- CODEX:
- coefficient:
- absorption coefficient: measure of how much light a substance absorbs
- J2: geopotential coefficient regarding a planet's oblateness
- coeval: the same age
- coherence:
- coherent dense core:
- coherent light: beam of light at a single frequency
- COHSI:
- Col:
- cold dark matter (CDM): one of three types of "dark matter" theory
- dark matter: matter suggested by gravity in galaxies and galaxy clusters
- fuzzy dark matter (FDM): concept of extremely light dark matter particles
- cold gas: gas cool enough to form galaxies and stars
- COLD GASS: survey of CO in nearby large galaxies
- cold mass accretion (CMA): stellar accretion through an accretion disk
- cold neutral medium:
- cold pixel:
- hot pixel: CCD pixel that shows more brightness than it should
- cold spot: unusually colder spot in the CMB
- cold start:
- cold trap: layer of atmosphere that prevents a gas from escaping by freezing it
- collapsar: neutron star or stellar black hole
- collapsar model:
- collecting area: cross-sectional area over which a telescope receives EMR
- colliding-wind binary:
- WR 140: Wolf-Rayet star that produces much dust
- collimate:
- collimated light:
- collimator: device to align beams of light
- Collinder:
- Collinder 50:
- Collinder Catalog (Cr): 1930s catalog of 471 open clusters
- collision:
- collision cross section:
- cross section: "area" representation of probability of an interaction of particles
- collisional:
- collisional broadening:
- collisional erosion: removing a body's substance through impacts
- collisionless Boltzmann equation:
- color:
- color excess:
- color index: a number that characterizes the color of an object
- reddening: red appearance of astronomical objects because blue light is attenuated by dust
- color index: a number that characterizes the color of an object
- color temperature (TC): temperature-measure of a source based on a color index
- color-color diagram (CCD): means of comparing characteristics of stars
- color-magnitude diagram (CMD,CM): graph plotting stars' color to luminosity
- color-period diagram: means of comparing periods of stars at various wavelengths
- Colossus Telescope: concept for a 50-meter telescope using interferometry
- column density: measure of the matter through which EMR is passing
- column mass density:
- column number density:
- Coma:
- Carbon Monoxide Mapping Array (COMA): planned experiment to observe epoch of reionization
- coma: aberration where points of light show a tail
- comet: Sun-orbiting object with coma and possible tail
- Stardust: space mission that collected and returned comet coma dust
- Coma Berenices:
- Coma Cluster:
- Coma Filament:
- Coma Supercluster: nearby supercluster
- Coma Wall:
- COMAP: high frequency radio telescope to map CO
- comatic aberration:
- coma: aberration where points of light show a tail
- Combined Array for Research in Millimeter-wave Astronomy (CARMA): array of radio telescopes in eastern California
- combined differential photometric precision (CDPP): calculated relation of photometric variation to SNR
- Combined Radio All-sky Targeted Eight-GHz Survey:
- CRATES: catalog of 8.4 GHz data on radio sources
- ComCam:
- comet: Sun-orbiting object with coma and possible tail
- Comet Astrobiology Exploration Sample Return:
- CAESAR: planned space mission to return a sample of a comet
- Comet Galaxy: spiral galaxy in cluster Abell 2667
- Comet Giacobini-Zinner:
- Comet Halley:
- Comet P/Shoemaker-Levy:
- comet: Sun-orbiting object with coma and possible tail
- comet planet: planet with some characteristics of a comet
- cometary globule:
- cometary hydrogen cloud:
- comet: Sun-orbiting object with coma and possible tail
- cometary nebula:
- comets:
- COMICS:
- commensal mode: telescope usage that accomplishes multiple observations simultaneously
- commensurability:
- orbital resonance: tendency of orbits of multiple bodies to remain in a simple pattern
- Commissariat à l'énergie atomique et aux énergies alternatives:
- Common Astronomy Software Application:
- CASA: software package for radio interferometry image generation
- common envelope: binary star system surrounded by a single gas cloud
- common envelope binary:
- common envelope binary event:
- common proper motion:
- proper motion (PM): apparent motion in relation to the position of the Sun
- Commonwealth Scientific and Industrial Research Organisation:
- comoving coordinates:
- comoving density of star formation:
- comoving distance:
- comoving horizon:
- comoving SFR density:
- comoving SFRD:
- comoving space density:
- comoving speed:
- comoving star formation rate density:
- comoving units: units of measure that incorporate the scale factor
- comoving volume:
- CoMP:
- compact binary:
- compact galaxy:
- compact group:
- galaxy group: group of fifty or fewer gravitationally bound Milky-Way-sized galaxies
- compact HII region:
- HII region (HII): cloud of partially-ionized atomic hydrogen
- compact object (CO): dense astronomical body such as white dwarf or denser
- compact object binary:
- compact object merger:
- compact object (CO): dense astronomical body such as white dwarf or denser
- Compact Object Mergers: Population Astrophysics and Statistics:
- COMPAS: SPS code for compact object binaries
- compact objects:
- COMPAS: SPS code for compact object binaries
- galactic binary: system of two object co-orbiting within the Milky Way
- Compact Objects with ASKAP: Surveys and Timing:
- compact star:
- compact object (CO): dense astronomical body such as white dwarf or denser
- compact stellar nucleus:
- COMPAS: SPS code for compact object binaries
- COMPLETE Survey: survey of star forming regions
- completeness: measure of how many of a survey's objects of a certain magnitude have been detected
- completeness limit:
- completeness: measure of how many of a survey's objects of a certain magnitude have been detected
- complex:
- complex crater: crater with central high-point
- complex numbers:
- Complex Visibility:
- visibility: mathematical representation of interferometer's view
- composite boson:
- composite remnant:
- compound:
- acetylene (C2H2): compound of two carbon and two hydrogen atoms
- amine: type of compound containing nitrogen
- ammonia (NH3): particular compound of nitrogen and hydrogen
- carbon dioxide (CO2): compound of carbon atom and two oxygen atoms
- carbon monoxide (CO): compound of carbon and oxygen, one atom each
- ethylene (C2H4): compound of two carbon and four hydrogen atoms
- glycine (Gly,G): smallest of the twenty common amino acids
- hydrocarbon (HC): any compound of just carbon and hydrogen
- hydrogen deuteride (HD): hydrogen molecule with one deuterium atom
- hydroxyl (OH): neutral compound of hydrogen and oxygen, one atom each
- methane (CH4): compound of one carbon and 4 hydrogen atoms
- methylidyne (CH): compound of one carbon and one hydrogen atom
- nitrite (NO2-): ion of a nitrogen atom and two oxygen atoms with extra electron
- polycyclic aromatic hydrocarbon (PAH): hydrocarbons consisting of meshes of benzene rings
- silicate: type of compound including silicon and oxygen
- compound lens:
- COMPTEL:
- Compton camera:
- Compton cooling:
- Compton scattering: photon collision with a charged particle that emits a different photon
- Compton effect:
- Compton scattering: photon collision with a charged particle that emits a different photon
- Compton Gamma Ray Observatory (CGRO,GRO): 1990s space observatory for gamma ray observation
- Compton optical depth:
- Compton parameter:
- Compton scattering: photon collision with a charged particle that emits a different photon
- Compton reflection: recognizable emission due to a gas or plasma's Compton scattering
- Compton scattering: photon collision with a charged particle that emits a different photon
- Compton telescope: type of gamma ray telescope for 0.75-30 MeV range
- Compton thick:
- Compton upscattering:
- Compton scattering: photon collision with a charged particle that emits a different photon
- Compton wavelength: lower bound on a particle's possible de Broglie wavelength
- Compton Y-parameter:
- Compton scattering: photon collision with a charged particle that emits a different photon
- Comptonization:
- Compton scattering: photon collision with a charged particle that emits a different photon
- computation:
- computational astrophysics: astrophysical study through computer modeling
- HARM²: technique for parallelizing computations of radiation with hydrodynamics
- computational fluid dynamics:
- Computational Infrastructure for Geodynamics:
- CIG: initiative to produce Earth-science software
- computational physics:
- computerized tomography scan:
- tomography: observation of sections of a 3D object
- computing:
- data cube: "table" of numerical data covering three dimensions
- exascale computing: exaFLOP computing capability, i.e., quintillion FLOPs
- concept:
- Concept 1:
- Concept 2:
- CONCERTO: spectrometer aimed at mapping the [CII] line
- concordance model:
- condensation:
- condensation temperature:
- conditional luminosity function (CLF): function characterizing luminosity of galaxies with a given halo mass
- conditional mass function:
- conditional stellar mass function (CSMF): function characterizing galaxies within a halo of a given mass
- conductance:
- siemens (S): SI unit of electrical conductance
- conduction:
- conductive hydrogen:
- metal: in astrophysics, any element more massive than helium
- metallic hydrogen: a high-pressure state of hydrogen that is conductive
- conductivity:
- siemens (S): SI unit of electrical conductance
- confidence interval:
- error bar: feature of a graph to indicate accuracy
- configuration:
- conformal field theory (CFT): a type of quantum field theory
- conformal mapping:
- conformal transformation:
- confusion:
- confusion limit: limit on telescope imaging due to too many sources in the same region
- confusion limit: limit on telescope imaging due to too many sources in the same region
- confusion-limited image:
- confusion limit: limit on telescope imaging due to too many sources in the same region
- conic section: orbit shapes, like the intersection of a plane and cone
- conjunction:
- CONSERT:
- Rosetta: space probe that visited a comet
- conservation law: property that remains unchanged by physical phenomena
- consortium:
- constant:
- constellation: division of the celestial sphere
- asterism: easily recognizable star pattern
- Orion: well-known constellation in the northern hemisphere
- constitutive equations:
- constitutive relations:
- construction:
- constructive interference:
- contact binary: binary stars orbiting so close they are touching
- contamination:
- completeness: measure of how many of a survey's objects of a certain magnitude have been detected
- continuous absorption: the absorption of a whole section of a spectrum
- continuous Galerkin method:
- continuous random variable:
- continuous shock:
- shock wave: abrupt propagating disturbance in a fluid
- continuous spectrum: smooth spectrum or portion of spectrum with no lines
- continuous viewing zone (CVZ): region of sky that can be viewed 7×24×365
- continuous-wave frequency-modulated:
- continuum: portion of a continuous spectrum not affected by a spectral feature
- continuum emission: continuous spectrum such as black body radiation or bremsstrahlung
- convection:
- convection zone: region of a star transmitting energy through convection
- convective mantle:
- dynamo: mechanism for generating magnetic fields around astronomical bodies
- convective parameterization:
- convective region:
- convective Rossby number:
- convective Urca process:
- convective zone:
- convergent point:
- convergent point method:
- convolution: type of product function of two functions
- convolutional neural network (CNN): type of image processing software
- U-Net: neural network software for image reconstruction
- COO:
- cool carbon star:
- carbon star (C): star with more carbon than oxygen in its atmosphere
- cool galactic carbon star:
- carbon star (C): star with more carbon than oxygen in its atmosphere
- cooling flow: inward flow of ICM within galaxy clusters
- Zwicky 3146 (Zw 3146,ZwCl 1021.0+0426): nearby large galaxy cluster
- cooling flow problem:
- cooling function: function relating a gas's cooling rate to its temperature
- cooling timescale:
- giant planet: planet of more than 10 Earth masses
- timescale (t,τ): general length of time something takes
- Cooper pair: pair of electrons sharing a particular type of bond
- coordinate:
- declination (dec): direction coordinate above/below celestial equator
- epoch: when an object was at a particular set of celestial coordinates
- meridian: circle around the Earth passing through both poles
- right ascension (RA): direction coordinate along celestial equator
- terrestrial time (TT): current measure of time for astronomical observations on Earth
- coordinate distance:
- coordinate system:
- Coordinated Molecular Probe Line Extinction Thermal Emission Survey:
- coordinated universal time:
- time standard: method of designating points in time and quantifying time periods
- coordinates:
- Coordinates, Sizes, Magnitudes, Orientation, and Shapes:
- Copernicus:
- coplanar flip:
- COPSS: survey of CO from star forming epoch
- Cordelia:
- Cordoba Durchmusterung:
- core:
- core accretion:
- core accretion model: model for the formation of giant planets
- core barrier:
- core collapse: results when the center of something loses its pressure
- core collapse progenitor:
- core collapse supernova (CCSN): supernova resulting from the collapse of the core of a star
- core collapse supernova progenitor:
- core flash:
- core mass function:
- core-cusp problem: theories and observation show different dwarf galaxy rotation curves
- core-driven escape:
- core-mantle boundary:
- Coriolis effect:
- Coriolis force: apparent force in a rotating frame of reference
- Hadley cell: circulation pattern of up at the equator, poleward, down, and back
- Coriolis force: apparent force in a rotating frame of reference
- CorMASS: near-infrared spectrograph
- Cornell Caltech Atacama Telescope:
- CCAT: 25-meter submillimeter telescope plan for Chile
- Cornell Massachusetts Slit Spectrograph:
- CorMASS: near-infrared spectrograph
- Cornell University:
- corona: plasma surrounding a star
- coronagraph: telescope feature to block light from a specific body
- coronagraphy:
- coronagraph: telescope feature to block light from a specific body
- coronal gas:
- coronal hole: cool, low-density portions of the Sun's corona
- coronal loop:
- coronal mass ejection (CME): mass of plasma ejected from the Sun
- Coronal Solar Magnetism Observatory (COSMO): proposed solar observatory
- COROT: observatory-satellite to look for transiting exoplanets and stellar oscillations
- corotation resonance (CR): an orbital resonance with the same frequency as the orbit
- corotation torque: torque on a planet from coorbiting planetary disk material
- corrected AIC:
- correction:
- gravity anomaly: difference between measured gravity and that predicted by a model
- Corrective Optics Space Telescope Axial Replacement:
- correlation function:
- correlator: unit that interferes wave signals for interferometry
- CORSA-b:
- Corvus:
- COS:
- COSAC:
- Rosetta: space probe that visited a comet
- COSI: 2000s balloon-based gamma ray telescope
- COSIMA:
- Rosetta: space probe that visited a comet
- COSMIC:
- Cosmic Anisotropy Polarization Mapper:
- CAPMAP: early 2000s array that surveyed CMB polarization
- Cosmic Anisotropy Telescope (CAT): 1990s interferometer to measure CMB variations
- Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS): early universe survey by HST
- Cosmic Background Explorer (COBE): 1989 satellite for observing the CMB
- Cosmic Background Imager (CBI): radio telescope in Chile observing the CMB
- cosmic background radiation (CBR): electromagnetic radiation coming from every direction
- cosmic censorship hypothesis:
- cosmic distance:
- cosmic distance ladder: sequence of methods of measuring distance to astronomical objects
- standard siren: transient whose gravitational waves indicate a specific distance
- cosmic distance scale:
- cosmic dust: cosmic dust is dust in space such as interstellar dust
- Cosmic Dust Analyzer:
- Cassini: explorer spacecraft sent to Saturn
- Cosmic Evolution Survey (COSMOS): investigation of dark matter and the universe's large scale structure
- Cosmic Explorer: concept for a very large LIGO-like GW detector
- Cosmic Explorer 1:
- Cosmic Explorer 2:
- cosmic gamma ray background (CGB): gamma-ray radiation seen everywhere
- cosmic high noon:
- Cosmic Hot Interstellar Plasma Spectrometer Satellite:
- CHIPSat: small satellite to investigate ISM plasma
- cosmic inflation:
- inflation: theorized rapid expansion of the very early universe
- cosmic infrared background (CIB,CIBR): widespread infrared radiation not associated with known sources
- cosmic lens:
- current sheet: narrow sheet within a magnetic field where current flows
- Cosmic Lens All-sky Survey (CLASS): radio survey aimed at gravitational lenses
- cosmic light horizon:
- cosmic microwave background (CMB,CMBR,CBR,MBR): microwave radiation coming from every direction
- cosmic microwave background dipole:
- cosmic microwave background radiation:
- cosmic neutrino background:
- cosmic noon:
- cosmic optical background (COB): widespread optical radiation not associated with known sources
- cosmic ray astronomy:
- cosmic rays (CR): very-high-energy particles from beyond the solar system
- cosmic ray background:
- cosmic rays (CR): very-high-energy particles from beyond the solar system
- cosmic ray spallation:
- cosmic rays (CR): very-high-energy particles from beyond the solar system
- cosmic ruler:
- cosmic string: rent in spacetime
- cosmic time: time since the Big Bang
- cosmic time dilation:
- cosmic variance: density variation on a cosmic scale
- cosmic void:
- void: empty spaces between large scale structures
- cosmic web: hypothesized structure of the dark matter throughout the universe
- cosmic X-ray background (CXB,CXRB,CXBR): X-ray radiation coming from outside the Milky Way
- cosmic X-ray background radiation:
- cosmic X-ray survey:
- X-ray: electromagnetic radiation, wavelength 0.01 to 10 nanometers
- cosmic year:
- COSMO:
- COSMO11:
- COSMO15:
- cosmogony:
- cosmological:
- cosmological band shifting:
- cosmological constant (Λ): force counteracting the universe's inward gravitational pull
- cosmological distance ladder:
- cosmological horizon:
- cosmological inflation:
- inflation: theorized rapid expansion of the very early universe
- cosmological models:
- cosmological principle: on a large scale the universe is the same everywhere
- cosmological redshift:
- redshift (z): change to longer wavelengths due to Doppler effects
- cosmological simulation: simulation of the history of the universe
- cosmological simulations:
- cosmic web: hypothesized structure of the dark matter throughout the universe
- dark matter filament: hypothesized type of long, thin volume of dark matter
- Cosmological Structures On Medium Angular Scales:
- cosmological time dilation: very distant events appear to take longer
- time dilation: relativity's ability to make time differ for different objects
- cosmological zoom simulation: cosmological simulation plus higher resolution simulations of selected space
- cosmology: study of the life of the universe
- Cosmology Large Angular Scale Surveyor:
- cosmology simulation:
- COSMOS:
- COSMOS Field:
- COSMOSOMAS: microwave survey
- COSPIN:
- Ulysses: space mission to observe the Sun from off the ecliptic
- COSTAR:
- COSTEP:
- COU:
- coudé focus:
- coudé focus telescope: type of Nasmyth telescope with additional mirrors
- coulomb:
- tesla (T): unit of magnetic flux density
- Coulomb force:
- Coulomb scattering:
- Coulomb's constant:
- Coulomb's law: static electrical force relation
- Council of Giants: twelve large galaxies surrounding the Local Group
- counterpart: image found at same coordinates using different EMR
- coupling constant:
- Courant condition:
- Courant-Friedrichs-Lewy-condition:
- covalent bond:
- CP:
- CP 1919:
- pulsar (PSR): type of astronomical body with EMR in regular cycles of seconds or less
- CP star:
- CP symmetry:
- axion (A0): proposed light, electrically neutral elementary particle
- CP1:
- CP2:
- CP3:
- CP4:
- CPC:
- IRAS: 1983 satellite that surveyed the sky in infrared
- CPD:
- CPO:
- CPR:
- CR:
- Crab Nebula (M1): supernova remnant in Taurus
- Crab Pulsar:
- crab-type remnant:
- CRaTER:
- Crater 2:
- CRATES: catalog of 8.4 GHz data on radio sources
- CRB:
- cosmic rays (CR): very-high-energy particles from beyond the solar system
- CRIRES: high resolution IR echelle spectrometer
- CRIRES+:
- CRIRES: high resolution IR echelle spectrometer
- CRIS:
- CRISM:
- critical density (ρc): density of the universe which leaves it flat
- critical density of the universe:
- critical point:
- critical radius:
- critical rotation:
- critical velocity:
- CRL:
- cross dispersion spectrograph: echelle spectrograph with additional disperser crosswise to the first
- cross Dragone:
- cross Dragone telescope:
- cross section: "area" representation of probability of an interaction of particles
- crossed-Dragone design:
- crowdsource:
- Galaxy Zoo: crowdsourcing website to identify galaxy types from surveys
- Galaxy Zoo 2 (GZ2): crowd-sourced classification of hundreds of thousands of galaxies
- Planet Hunters (PH): crowdsourcing website to identify galaxy types from surveys
- CRS:
- Voyager: space probes to observe planets and the edge of the solar system
- CRTS:
- crust:
- crustal magnetism: magnetic fields independent of a world's core magnetic field
- crustal plates: sections of the Earth's crust that move
- cryogenic:
- Cryogenic Infrared Echelle Spectrometer:
- CRIRES: high resolution IR echelle spectrometer
- cryogenic spectroscopy: laboratory spectroscopy of materials cooled to cryogenic temperatures
- cryolava:
- cryovolcano: eruption of substances that are liquid or gas at cold temperatures
- cryovolcanism:
- cryovolcano: eruption of substances that are liquid or gas at cold temperatures
- cryovolcano: eruption of substances that are liquid or gas at cold temperatures
- crystal ice:
- snow line: distance from protostar cool enough for water to condense
- crystal nucleation:
- supercooling: cooling water below freezing point without it freezing
- crystal nucleus:
- supercooling: cooling water below freezing point without it freezing
- crystalline ice:
- ice: solid state of water
- CS:
- tracer: chemical whose presence indicates the presence of another chemical
- CS60:
- CSA: includes astronomical research
- James Webb Space Telescope (JWST): future space-based 6.5 meter infrared telescope
- MOST: 2000s observatory-satellite looking for stellar oscillations
- NEOSSat: small spacecraft tracking NEOs
- CSE:
- CSHELL:
- IRTF: Mauna Kea 3-meter infrared telescope
- CSI:
- CSIRO:
- CSM:
- CSMF:
- CSN:
- CSO:
- CSO-JCMT interferometer:
- CSP:
- CSPN:
- CSPNe:
- CSS:
- CSV:
- CT scan:
- tomography: observation of sections of a 3D object
- CTA:
- CTB:
- CTIO:
- CTIO 1.5m:
- CTIO Schmidt Camera:
- CTIO Upper-Scorpius OB Association Survey (UScoCTIO): survey of low-mass stars and brown dwarfs
- CTTS:
- CTX:
- cubewano:
- Kuiper Belt (K Belt,KB): further part of solar system beyond Neptune
- Curiosity:
- curl:
- current:
- siemens (S): SI unit of electrical conductance
- current sheet: narrow sheet within a magnetic field where current flows
- Curtis-Shapley Debate:
- Great Debate: historical debate regarding the nature of galaxies
- curvature: unflatness of space
- wormhole: connection between two regions in a curved space
- curvature fluctuation amplitude:
- Lambda-CDM model (ΛCDM,LCDM): Big-Bang cosmological model with a cosmological constant and cold dark matter
- curvature radiation: synchrotron-like radiation when particles follow curved field lines
- curvature scalar:
- curvature sensor:
- curve of growth:
- curved space:
- cusp:
- core-cusp problem: theories and observation show different dwarf galaxy rotation curves
- cut-off frequency:
- CV:
- CvB:
- CVZ:
- CWFM:
- CWI:
- CXB:
- CXBR:
- CXC:
- CXE:
- HEAO-1: 1977 X-ray observatory space mission
- CXO:
- CXOU:
- CXRB:
- Cybele:
- cycloalkane:
- hydrocarbon (HC): any compound of just carbon and hydrogen
- cyclotron:
- cyclotron frequency:
- cyclotron radiation: radiation emitted when charged particles are accelerated
- Cygnus A (3C 405,QSO B1957+405): early-discovered radio galaxy and quasar
- Cygnus OB2-12:
- Cygnus X Star Forming Region:
- cylindrical radio telescope:
- cylindrical telescope: telescope with cylindrical reflectors
- Cz:
- Czernik:
- Czernik Catalog (Cz): list of open clusters
- Czernik Open Cluster Catalogue:
Index