HD 213402
K-type giant in the constellation Octans / From Wikipedia, the free encyclopedia
HD 213402 (HR 8577; 73 G. Octantis) is a solitary star located in the southern circumpolar constellation Octans. It has an apparent magnitude of 6.14,[2] placing it near the limit for naked eye visibility. The object is located relatively far at a distance of 920 light-years based on Gaia DR3 parallax measurements,[1] but it is drifting closer with a heliocentric radial velocity of −12.8 km/s.[5] At its current distance, HD 213402's brightness is diminshed by 0.45 magnitudes due to interstellar extinction[15] and it has an absolute magnitude of −1.15.[6]
Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
---|---|
Constellation | Octans |
Right ascension | 22h 35m 26.52327s[1] |
Declination | −78° 46′ 17.7049″[1] |
Apparent magnitude (V) | 6.14±0.01[2] |
Characteristics | |
Evolutionary stage | red giant branch[1] |
Spectral type | K1 III[3] |
U−B color index | +1.35[4] |
B−V color index | +1.38[4] |
Astrometry | |
Radial velocity (Rv) | −12.8±0.4[5] km/s |
Proper motion (μ) | RA: +53.718 mas/yr[1] Dec.: −7.451 mas/yr[1] |
Parallax (π) | 3.5469 ± 0.0256 mas[1] |
Distance | 920 ± 7 ly (282 ± 2 pc) |
Absolute magnitude (MV) | −1.15[6] |
Details | |
Mass | 1.17[7] M☉ |
Radius | 44.5±2.3[8] R☉ |
Luminosity | 471±8[9] L☉ |
Surface gravity (log g) | 1.16[10] cgs |
Temperature | 4,481±122[11] K |
Metallicity [Fe/H] | −0.07[7] dex |
Rotational velocity (v sin i) | <1.0[12] km/s |
Other designations | |
Database references | |
SIMBAD | data |
HD 213402 has a stellar classification of K1 III,[3] indicating that it is an evolved K-type giant. It has a comparable mass to the Sun[7] but it has expanded to 44.5 times the radius of the Sun.[8] It radiates 471 times the luminosity of the Sun[9] from its enlarged photosphere at an effective temperature of 4,481 K,[11] giving it the typical orange hue of a K-type star. Gaia DR3 stellar evolution models place it on the red giant branch and yield a larger radius of 50.9 R☉ and a higher luminosity of 825 L☉.[1] HD 213402 is slightly metal deficient with an iron abundance of [Fe/H] = −0.07 or 85% of the Sun's abundance.[7] Like many giant stars it rotates slowly, but its projected rotational velocity is too low to be measured accurately.[12]