Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Octans |
Right ascension | 10h 59m 13.7578s[1] |
Declination | −84° 35′ 38.0177″[1] |
Apparent magnitude (V) | 6.18±0.01[2] |
Characteristics | |
Evolutionary stage | main sequence[3] |
Spectral type | A1 Va[4] |
U−B color index | +0.12[5] |
B−V color index | +0.11[5] |
Astrometry | |
Radial velocity (Rv) | −1.7±0.6[6] km/s |
Proper motion (μ) | RA: −65.747 mas/yr[1] Dec.: −8.273 mas/yr[1] |
Parallax (π) | 9.1133 ± 0.02 mas[1] |
Distance | 357.9 ± 0.8 ly (109.7 ± 0.2 pc) |
Absolute magnitude (MV) | +1.08[7] |
Details | |
Mass | 2.37±0.03[3] M☉ |
Radius | 2.6±0.1[8] R☉ |
Luminosity | 45.3+3.1 −3.0[3] L☉ |
Surface gravity (log g) | 4.1[9] cgs |
Temperature | 9,500[9] K |
Metallicity [Fe/H] | −0.01[10] dex |
Rotational velocity (v sin i) | 152±13[11] km/s |
Age | 547[10] Myr |
Other designations | |
Database references | |
SIMBAD | data |
Eta Octantis, Latinized from η Octantis, is a solitary star located in the southern circumpolar constellation Octans. It has an apparent magnitude of 6.19,[2] making it faintly visible to the naked eye. The object is situated at a distance of 358 light years[1] but is approaching the Solar System with a heliocentric radial velocity of −1.7 km/s.[6]
Eta Octantis has a stellar classification of A1 Va,[4] indicating that it is an ordinary A-type main sequence star. At present it has 2.37 times the Sun's mass[3] and 2.6 times the Sun's radius.[8] It shines with a luminosity of 45 L☉[3] from its photosphere at an effective temperature of 9,500 K, giving a white hue.[9] Eta Octantis is a rapidly rotating star, with a projected rotational velocity of 152 km/s,[11] and is estimated to be 547 million years old,[10] having completed 72% of its main sequence lifetime.[3]