| Astronomy Symbols |
| Age (stellar) |
| * τ - Age |
|
| Astrometry parameters |
| * Rv - radial velocity |
| * μ - proper motion |
| * π - parallax |
| * J - Epoch |
|
| Cosmological parameters |
| * h - Dimensionless Hubble parameter |
| * H0 - Hubble constant |
| * Λ - Cosmological constant |
| * Ω - Density parameter |
| * ρ - Density |
| * ρc - Critical density |
| * z - Redshift |
|
| Distance description |
| Distance description for Orbital and non-Orbital Parameters: |
| * d - distance |
| o d - in km = kilometer |
| o d - in mi = mile, note, not an SI unit |
| o d - in AU = astronomical unit |
| o d - in ly = light-year |
| o d - in kly = kilolight-year (1000 x 1ly) |
| o d - in pc = parsec |
| o d - in kpc = kiloparsec (1000 x 1pc) |
| * DL - Luminosity distance, obtaining an objects distance using only visual aspects |
|
| Galaxy comparism |
| Galaxy type and spectral comparism: |
| * see Galaxy morphological classification |
|
| Luminosity comparism: |
| * LS - Luminosity compared to the Sun (Sol) |
| * L☉ - Luminosity compared to the Sun (Sol) |
|
| Luminosity of certain object: |
| * Lacc - Accretion luminosity |
| * Lbol - Bolometric luminosity |
|
| Mass comparism: |
| * ME - Mass compared to Earth |
| * M⊕ - Mass compared to Earth |
| * MJ - Mass compared to Jupiter |
| * M♃ - Mass compared to Jupiter |
| * MS - Mass compared to the Sun (Sol) |
| * M☉ - Mass compared to The Sun (Sol) |
|
| Mass of certain object: |
| * M●[1] - Mass of black hole |
| * Macc - Mass of accretion disc |
|
| Metallicity comparism: |
| * Fe/H - Iron ratio to Hydrogen |
| * M/H - Metallicity ratio. |
| * Z - Metallicity |
| * ZS - Metallicity compared to the Sun (Sol) |
| * Z☉ - Metallicity compared to the Sun (Sol) |
|
| Orbital parameters |
| Orbital Parameters of a Cosmic Object: |
| * α - RA, right ascension, if the Greek letter does not appear, á letter will appear. |
| * δ - Dec, declination, if the Greek letter does not appear, ä letter will appear. |
| * P or Porb - orbital period |
| * a - semi-major axis |
| * b - semi-minor axis |
| * q - periapsis, the minimum distance |
| * Q - apsis, the maximum distance |
| * e - eccentricity |
| * i - inclination |
| * Ω - longitude of ascending node |
| * ω - argument of periapsis |
| * RL - Roche lobe |
| * M - Mean anomaly |
| * Mo - Mean anomaly at epoch |
|
| Radius comparism: |
| * RE - Radius compared to Earth |
| * R⊕ - Radius compared to Earth |
| * RJ - Radius compared to Jupiter |
| * R♃ - Radius compared to Jupiter |
| * RS - Radius compared to The Sun (Sol) |
| * R☉ - Radius compared to The Sun (Sol) |
|
| Spectral comparism: |
| * see Stellar classification |
| * m(object) - Apparent magnitude |
| * M(object) - Absolute magnitude, for galaxies and stars |
| * H(object) - Absolute magnitude, for planets and nonstellar objects |
|
| Temperature description: |
| * Teff - Temperature Effect, usually associated with luminous object |
| * Tmax - Temperature Maximum, usually associated with non-luminous object |
| * Tavg - Temperature Average, usually associated with non-luminous object |
| * Tmin - Temperature Minimum, usually associated with non-luminous object |
| * K - Kelvin |
