| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Cetus | 
| Right ascension | 03h 12m 46.43719s [1] | 
| Declination | −01° 11′ 45.9613″ [1] | 
| Apparent magnitude (V) | +5.070 [2] | 
| Characteristics | |
| Spectral type | F8V / M3V / M | 
| U−B color index | +0.09 [3] | 
| B−V color index | +0.56 [3] | 
| Astrometry | |
| Radial velocity (Rv) | +18.96 ± 0.08 [4] km/s | 
| Proper motion (μ) | RA: 194.56 [1]  mas/yr Dec.: −69.01 [1] mas/yr | 
| Parallax (π) | 44.29±0.28 mas [1] | 
| Distance | 73.6 ± 0.5  ly (22.6 ± 0.1 pc) | 
| Absolute magnitude (MV) | 3.32 | 
| Orbit [5] | |
| Primary | 94 Ceti A | 
| Companion | 94 Ceti BC | 
| Period (P) | 2029±41 yr | 
| Semi-major axis (a) | 220±5 AU | 
| Eccentricity (e) | 0.26±0.01 | 
| Inclination (i) | 104±2° | 
| Longitude of the node (Ω) | 97±2° | 
| Argument of periastron (ω) (secondary) | 342±7° | 
| Orbit [6] | |
| Primary | 94 Ceti B | 
| Companion | 94 Ceti C | 
| Period (P) | 378.35+0.36 −0.34 d | 
| Semi-major axis (a) | 0.984±0.007 AU | 
| Eccentricity (e) | 0.360±0.005 | 
| Inclination (i) | 108.323+0.581 −0.561° | 
| Longitude of the node (Ω) | 191.496+1.602 −1.562° | 
| Periastron epoch (T) | MJD 55113.904±0.220 | 
| Argument of periastron (ω) (secondary) | 334.895±0.240° | 
| Details | |
| Mass | 1.30 [7] M☉ | 
| Radius | 1.898 ± 0.070 [8] R☉ | 
| Luminosity | 4.02 ± 0.05 [9] L☉ | 
| Surface gravity (log g) | 3.98 ± 0.10 [7] cgs | 
| Temperature | 6,055 ± 10.0 [10] K | 
| Metallicity [Fe/H] | 1.15 ± 0.07 [7] dex | 
| Rotation | 12.2 d [11] | 
| Rotational velocity (v sin i) | 8.4 ± 0.8 [7] km/s | 
| Age | 4.8 [9] Gyr | 
| Other designations | |
| BD−01°457, FK5 116, GJ 128, HD 19994, HIP 14954, HR 962, LTT 1515, SAO 130355 | |
| Database references | |
| SIMBAD | data | 
94 Ceti (HD 19994) is a trinary star system approximately 73 light-years away in the constellation Cetus.
94 Ceti A is a yellow-white dwarf star with about 1.3 times the mass of the Sun while 94 Ceti B and C are red dwarf stars.
An infrared excess has been detected around the primary, most likely indicating the presence of a circumstellar disk at a radius of 95 AU. The temperature of this dust is 40 K. [12]
This system is a hierarchical triple star system with 94 Ceti A being orbited by 94 Ceti BC, a pair of M dwarfs, in 2000 years. 94 Ceti B and C meanwhile orbit each other in a 1-year orbit. [5]
On 7 August 2000, a planet was announced by the Geneva Extrasolar Planet Search team as a result of radial velocity measurements taken with the Swiss 1.2-metre Leonhard Euler Telescope at La Silla Observatory in Chile. [13] It is most stable if its inclination is either 65 or 115, ± 3. [14]
| Companion (in order from star) | Mass | Semimajor axis (AU) | Orbital period (days) | Eccentricity | Inclination | Radius | 
|---|---|---|---|---|---|---|
| b | 1.855 ± 0.045 MJ | 1.427 | 535.7 ± 3.1 | 0.30 ± 0.04 | — | — |