| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Auriga |
| Right ascension | 05h 52m 40.09222s[1] |
| Declination | +33° 55′ 02.8721″[1] |
| Apparent magnitude (V) | 6.04[2] (5.82–6.07)[3] |
| Characteristics | |
| Evolutionary stage | AGB[4] |
| Spectral type | M1+III Fe-1[5] |
| U−Bcolor index | 1.97 |
| B−Vcolor index | 1.579±0.021 |
| Variable type | suspected[3] |
| Astrometry | |
| Radial velocity (Rv) | 98.35±0.53[1] km/s |
| Proper motion (μ) | RA: 18.569[1]mas/yr Dec.: 8.812[1]mas/yr |
| Parallax (π) | 5.2412±0.1841 mas[1] |
| Distance | 620 ± 20 ly (191 ± 7 pc) |
| Absolute magnitude (MV) | −0.77[2] |
| Details | |
| Radius | 43.0±3.5[1] R☉ |
| Luminosity | 398.6±16.2[1] L☉ |
| Temperature | 3,934±51[6] K |
| Other designations | |
| BD+33°1179,HD 39225,HIP 27778,HR 2028,SAO 58528,GSC 02414-00524[7] | |
| Database references | |
| SIMBAD | data |
HD 39225, also known asHR 2028, is avariable star in the northern constellationAuriga, located around 620 light years away from the Sun. It is visible to the naked eye as a faint, red-hued star with anapparent visual magnitude of around 6.04.[2] This is a suspectedrunaway star[8] that is moving away from the Sun with a heliocentricradial velocity of 98 km/s.[1]
Currently on theasymptotic giant branch,[4] this is anevolvedred giant star with astellar classification ofM1+III Fe-1.[5] The suffix notation indicates an underabundance of iron in thestellar atmosphere compared to similar stars of its class. It is suspected of varying in brightness between magnitudes 5.82 and 6.07.[3] Having exhausted the hydrogen at itscore, it has expanded to around 43 times theSun's radius.[1] It shines with aluminosity approximately 398.6[1] times that of the Sun and has a surface temperature of 3,934 K.[6]
