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 | |
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 | — | — |
70 Virginis is a binary star located 59 light years from the Sun in the equatorial constellation of Virgo, near the northern constellation border with Coma Berenices. 70 Virginis is its Flamsteed designation. The star is visible to the naked eye as a faint, yellow-hued point of light with an apparent visual magnitude of +4.97. It is drifting further away with a heliocentric radial velocity of +4.4 km/s and has a high proper motion, traversing the celestial sphere at the rate of 0.621 arc seconds per annum.
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HD 147513 is a star in the southern constellation of Scorpius. It was first catalogued by Italian astronomer Piazzi in his star catalogue as "XVI 55". With an apparent magnitude of 5.38, according to the Bortle scale it is visible to the naked eye from suburban skies. Based upon stellar parallax measurements by the Hipparcos spacecraft, HD 147513 lies some 42 light years from the Sun.
Groombridge 34 is a binary star system in the northern constellation of Andromeda. It was listed as entry number 34 in A Catalogue of Circumpolar Stars, published posthumously in 1838 by British astronomer Stephen Groombridge. Based upon parallax measurements taken by the Gaia spacecraft, the system is located about 11.6 light-years from the Sun. This positions the pair among the nearest stars to the Solar System.
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AB Pictoris is a K-type main-sequence star, located 163.5 light-years away in the southern constellation of Pictor. It has been identified as a member of the young Tucana–Horologium association. The star has been classified as a BY Draconis variable, indicating it has an active chromosphere. It is an X-ray source and displays emission lines in its spectrum.
Gliese 105 is a triple star system in the constellation of Cetus. It is located relatively near the Sun at a distance of 23.6 light-years. Despite this, even the brightest component is barely visible with the unaided eye (see Bortle scale). No planets have yet been detected around any of the stars in this system.
Theta Cygni is a star in the northern constellation of Cygnus. It has an apparent visual magnitude of 4.5, so it can be seen with the naked eye in sufficiently dark skies. Based upon parallax measurements, it is at a distance of about 59.8 light-years from the Earth. It is suspected of hosting an extrasolar planet.
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HD 11964 is a binary star system located 110 light-years away from the Sun in the equatorial constellation of Cetus. It is visible in binoculars or a telescope but is too faint to be seen with the naked eye, having an apparent visual magnitude of 7.51. The system is drifting closer to the Sun with a radial velocity of −9 km/s. Two extrasolar planets have been confirmed to orbit the primary.
HD 16175 is a 7th magnitude G-type star with temperature about 6000 K located 196 light-years away in the Andromeda constellation. This star is only visible through binoculars or better equipment; it is also 3.3 times more luminous, is 1.34 times more massive, and has a radius 1.66 times bigger than our local star.
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