Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
---|---|
Constellation | Octans |
Right ascension | 12h 54m 58.80949s[1] |
Declination | −85° 07′ 24.1041″[1] |
Apparent magnitude (V) | 5.83 + 6.75[2] |
Characteristics | |
Spectral type | K0 III[3] |
U−B color index | +0.79[4] |
B−V color index | +1.02[4] |
Astrometry | |
Radial velocity (Rv) | 53.4±0.7[5] km/s |
Proper motion (μ) | RA: +67.20[1] mas/yr Dec.: +24.76[1] mas/yr |
Parallax (π) | 9.27 ± 0.46 mas[1] |
Distance | 350 ± 20 ly (108 ± 5 pc) |
Absolute magnitude (MV) | +0.29 |
Details[6] | |
Mass | 2.49+1.48 −1.31 M☉ |
Radius | 12.43[7] R☉ |
Luminosity | 81±9 L☉ |
Temperature | 4,890±110 K |
Metallicity [Fe/H] | −0.3 dex |
Rotational velocity (v sin i) | 1.9±1.3[8] km/s |
Age | 725[9] Myr |
Other designations | |
ι Octantis, 16 G. Octantis, CPD−84°407, GC 17460, HD 111482, HIP 63031, HR 4870, SAO 258654, WDS J12550-8507AB | |
Database references | |
SIMBAD | data |
Iota Octantis, Latinized, from ι Octantis is a double star[10] in the southern circumpolar constellation Octans. The "A" component has an apparent magnitude of 5.83,[2] making it faintly visible to the naked eye under ideal conditions, but the "B" component can't be seen due to its faintness.[2] The system is located at a distance of 350 light years[1] based on its annual parallax shift, but is drifting away at a rate of 53.4 km/s.[5]
Iota Octantis A has a classification of K0 III,[3] which indicates that it is an evolved K-type star that exhausted hydrogen at its core and left the main sequence. It has an angular diameter of 1.07 arcseconds,[11] which yields a radius 12.43 times that of the Sun at its estimated distance.[7] At present Iota Octantis A has 2.49 times the mass of the Sun[6] and radiates at 81 times the luminosity of the Sun[6] from its enlarged photosphere at an effective temperature of 4,890 K,[6] which gives it an orangish-yellow hue. Iota Octantis is metal deficient[6] and spins slowly with a projected rotational velocity of 1.9 km/s.[8]
Eggleton et al. states that both stars have similar spectral types,[10] but there is a faint tenth magnitude companion with a classification of F8 located 60.1″ away,[12] which is unrelated to the two.