| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Cetus |
| Right ascension | 01h56m 40.20314s[1] |
| Declination | −22° 31′ 36.4091″[1] |
| Apparent magnitude (V) | 4.85[2] |
| Characteristics | |
| Spectral type | K3III[3] |
| U−B color index | +1.67[4] |
| B−V color index | +1.434±0.005[5] |
| Astrometry | |
| Radial velocity (Rv) | +27.38±0.80[1] km/s |
| Proper motion (μ) | RA: +59.881[1] mas/yr Dec.: −25.633[1] mas/yr |
| Parallax (π) | 7.3878 ± 0.1861 mas[1] |
| Distance | 440 ± 10 ly (135 ± 3 pc) |
| Absolute magnitude (MV) | −0.25[5] |
| Details | |
| Radius | 39.20+1.15 −2.93[1] R☉ |
| Luminosity | 391+11 −20[1] L☉ |
| Surface gravity (log g) | 1.85[2] cgs |
| Temperature | 4,099+163 −59[1] K |
| Metallicity [Fe/H] | −0.18[2] dex |
| Other designations | |
56 Cet, CD−23°721, GC 2343, HD 11930, HIP 9061, HR 565, SAO 167416[6] | |
| Database references | |
| SIMBAD | data |
56 Ceti is a single[7] star located in the equatorial constellationofCetus. Not found in the original Bayer catalogue, it was given the Bayer-like designation Upsilon1 CetibyFlamsteed[8] to distinguish it from Bayer's Upsilon Ceti, which Flamsteed designated Upsilon2 or 59 Ceti. In 1801, J. E. Bode included this designation in his Uranographia,[9] but the superscripted designations Upsilon1 and Upsilon2 are not in general use today. 56 Ceti is the Flamsteed designation for this star.
This star is visible to the naked eye as a faint, orange-hued point of light with an apparent visual magnitude of 4.85.[2] It is located about 440 light years from the Sun, based on parallax, and is drifting further away with a radial velocity of +27 km/s.[1] 56 Ceti is an aging giant star with a stellar classification of K3III,[3] having exhausted the supply of hydrogen at its core and expanded to 39[1] times the Sun's radius. It is radiating 391[1] times the luminosity of the Sun from its enlarged photosphere at an effective temperature of 4,099 K.[1]
