94 Ceti

Last updated

94 Ceti A / B
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]
Primary94 Ceti A
Companion94 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]
Primary94 Ceti B
Companion94 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.

Contents

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]

Stellar system

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]

Planetary system

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]

The 94 Ceti planetary system [14]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b 1.855 ± 0.045  MJ 1.427535.7 ± 3.10.30 ± 0.04

See also

Related Research Articles

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References

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