Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
---|---|
Constellation | Octans |
Right ascension | 18h 54m 47.14062s[1] |
Declination | −87° 36′ 21.0359″[1] |
Apparent magnitude (V) | 5.28±0.01[2] |
Characteristics | |
Spectral type | K3 III[3] |
U−B color index | +1.60[4] |
B−V color index | +1.28[4] |
Astrometry | |
Radial velocity (Rv) | 33.6±3.1[5] km/s |
Proper motion (μ) | RA: −36.555 mas/yr[1] Dec.: −135.715 mas/yr[1] |
Parallax (π) | 12.5114 ± 0.0730 mas[1] |
Distance | 261 ± 2 ly (79.9 ± 0.5 pc) |
Absolute magnitude (MV) | +0.81[6] |
Details | |
Mass | 1.25±0.33[7] M☉ |
Radius | 15.6±0.8[8] R☉ |
Luminosity | 73.6±0.7[9] L☉ |
Surface gravity (log g) | 2.19[10] cgs |
Temperature | 4,266+99 −97[7] K |
Metallicity [Fe/H] | +0.10[10] dex |
Rotational velocity (v sin i) | <1[11] km/s |
Other designations | |
Database references | |
SIMBAD | data |
Chi Octantis, Latinized from χ Octantis, is a solitary star[14] located in the southern circumpolar constellation Octans. It is faintly visible to the naked eye as an orange-hued star with an apparent magnitude of 5.28.[2] The object is located relatively close at a distance of 261 light years based on Gaia EDR3 parallax measurements,[1] but it is receding with a heliocentric radial velocity 33.6 km/s.[5] At its current distance, Chi Octantis' brightness is diminished by 0.24 magnitudes due to interstellar dust.[15] It has an absolute magnitude of +0.81.[6]
Chi Octantis is an evolved red giant with a stellar classification of K3 III.[3] It has 125% the mass of the Sun and an enlarged radius of 14.45 R☉ due to its evolved state.[7] It radiates 73.6 times the luminosity of the Sun[9] from its photosphere at an effective temperature of 4,266 K.[7] Chi Octantis is metal enriched with an iron abundance 126% that of the Sun ([Fe/H] = +0.10)[10] and spins slowly with a projected rotational velocity less than 1 km/s−1.[11]