| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Columba |
| Right ascension | 05h53m 22.85088s[1] |
| Declination | −42° 55′ 16.7853″[1] |
| Apparent magnitude (V) | 6.54±0.01[2] |
| Characteristics | |
| Spectral type | K3 III[3] |
| B−V color index | +1.37[4] |
| Astrometry | |
| Radial velocity (Rv) | −10.3±0.4[5] km/s |
| Proper motion (μ) | RA: +5.109 mas/yr[1] Dec.: +11.405 mas/yr[1] |
| Parallax (π) | 5.1076 ± 0.0152 mas[1] |
| Distance | 639 ± 2 ly (195.8 ± 0.6 pc) |
| Absolute magnitude (MV) | −0.03[6] |
| Details | |
| Mass | 1.27[7] M☉ |
| Radius | 21.9[8] R☉ |
| Luminosity | 143±1[9] L☉ |
| Surface gravity (log g) | 1.87[7] cgs |
| Temperature | 4,373±122[10] K |
| Metallicity [Fe/H] | +0.08[11] dex |
| Rotational velocity (v sin i) | <1.6[12] km/s |
| Other designations | |
59 G. Columbae[13], CD−42°2205, CPD−42°769, GC 7431, HD 39901, HIP 27835, HR 2069, SAO 217599[14] | |
| Database references | |
| SIMBAD | data |
HD 39901 is an orange hued star located in the constellation Columba. It is also called HR 2069, which is the star's Bright Star Catalog designation. Eggen (1989) lists it as a member of the old disk population.[11]
Despite the HR designation, the object has an apparent magnitude of 6.54,[2] slightly past the limit for the naked eye visibility. As a result, it is barely visible to the unaided eye in the best conditions. Parallax measurements from the Gaia spacecraft place the object 639 light years away.[1] It is approaching the Solar System with a heliocentric radial velocityof−10.3 km/s.[5] At that distance, HD 39901's brightness is diminished by 0.33 magnitudes due to interstellar dust.[15] It has an absolute magnitude of −0.03.[6]
This is an evolved red giant star with a stellar classification of K3 III.[3] It has a comparable mass to the Sun[7] but has expanded to 21.9 times the latter's girth.[8] It radiates 143 times the luminosity of the Sun[9] from its photosphere at an effective temperature of 4,373 K.[10] HD 39901 is slightly enriched in heavy elements with a metallicity 120% that of the Sun's.[11] Like most giants, it spins slowly, having a projected rotational velocity lower than 1.6 km/s.[12]
