| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Antlia |
| Right ascension | 09h29m 54.5048s[1] |
| Declination | −26° 35′ 22.6154″[1] |
| Apparent magnitude (V) | 5.48±0.01[2] |
| Characteristics | |
| Spectral type | K3 III[3] |
| B−V color index | +1.36[4] |
| Astrometry | |
| Radial velocity (Rv) | 12±2[5] km/s |
| Proper motion (μ) | RA: −21.883 mas/yr[1] Dec.: +0.761 mas/yr[1] |
| Parallax (π) | 4.0447 ± 0.0731 mas[1] |
| Distance | 810 ± 10 ly (247 ± 4 pc) |
| Absolute magnitude (MV) | −1.42[6] |
| Details | |
| Mass | 4.46[7] M☉ |
| Radius | 38.86[8] R☉ |
| Luminosity | 552[9] L☉ |
| Surface gravity (log g) | 1.61±0.01[10] cgs |
| Temperature | 4,413±122[8] K |
| Metallicity [Fe/H] | +0.09[11] dex |
| Rotational velocity (v sin i) | <1[12] km/s |
| Other designations | |
3 G. Antliae[13], CD−26°7117, GC 13110, HD 82205, HR 3770, SAO 177546, WDS J09299-2635A[14] | |
| Database references | |
| SIMBAD | data |
HD 82205 (HR 3770) is a solitary star[15] in the southern constellation Antlia. It is faintly visible to the naked eye with an apparent magnitude of 5.48[2] and is estimated to be 810 light years[1] distant based on parallax measurements. However, it is receding with a heliocentric radial velocityof12 km/s.[5]
HD 82205 has a general stellar classification of K3 III, indicating that it is a red giant. However, Houk and Cowley (1982) found a slightly warmer class of K2 III CNII,[16] which also suggests a strong overabundance of cyano radicals in the stellar atmosphere. At present it has 4.46 times the mass of the Sun[7] but has expanded to 38.9 times its girth.[8] It shines with a luminosityof552 L☉[9] from its enlarged photosphere at an effective temperatureof4,413 K,[8] giving an orange hue. HD 82205 has a metallicity 123% that of the Sun and is believed to be a member of the thin disk population.[11] Currently, it spins with a projected rotational velocity lower than 1 km/s.[12]
There is a 14th magnitude optical companion separated 12.4 arcseconds away along a position angleof131°.[17] The object was first noticed by T.J.J See in 1897.[18]
