HD 108863 is a subgiant star, the primary of a binary star system 540 light-years away, belonging to spectral class K0. Its age is younger than the Sun's at 1.8±0.4 billion years.[8] The primary star is slightly enriched in heavy elements, having 115% of solar abundance.[7] The primary star does not have detectable flare activity.[9]
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Coma Berenices |
Right ascension | 12h 30m 19.9101s[1] |
Declination | +21° 56′ 53.6794″[1] |
Apparent magnitude (V) | 7.71[2] |
Characteristics | |
Evolutionary stage | subgiant |
Spectral type | K0III-IV[3] |
B−V color index | 0.99[4] |
Astrometry | |
Radial velocity (Rv) | −27.832 km/s |
Proper motion (μ) | RA: −75.501 mas/yr Dec.: −33.669 mas/yr |
Parallax (π) | 6.0417 ± 0.0485 mas[5] |
Distance | 540 ± 4 ly (166 ± 1 pc) |
Orbit[6] | |
Primary | HD 108863 |
Companion | HD 108863 B |
Semi-major axis (a) | 0.115" (16.065 AU) |
Details[2] | |
Mass | 1.59 M☉ |
Radius | 5.74 R☉ |
Surface gravity (log g) | 3.07 cgs |
Temperature | 4,878 K |
Metallicity | 0.02[7] |
Rotational velocity (v sin i) | 1.6±0.6[7] km/s |
Age | 1.8±0.4[8] Gyr |
Other designations | |
Database references | |
SIMBAD | data |
In 2014, a poorly characterized co-moving stellar companion HD 108863 B, likely a main sequence star of spectral class between F6 and G4, was discovered at a projected separation of 16.065 AU.[6]
In 2011 one superjovian planet, HD 108863 b, on a nearly circular orbit around star HD 108863 was discovered utilizing the radial velocity method.[4] The planet does not transit its host star.[2]
Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
HD 108863 b | ≥2.6±0.2 MJ | 1.40±0.03 | 443.4±4.2 | <0.1 | — | — |