  | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Auriga |
| Right ascension | 05h 36m 52.41522s[1] |
| Declination | +40° 10′ 56.5783″[1] |
| Apparent magnitude (V) | 6.08[2] |
| Characteristics | |
| Spectral type | G3 Ib[3] + B7 V?[4] |
| U−Bcolor index | 0.69[2] |
| B−Vcolor index | 1.03[2] |
| Astrometry | |
| Radial velocity (Rv) | −12.06±0.03[4] km/s |
| Proper motion (μ) | RA: −2.99±1.03[5]mas/yr Dec.: −4.56±0.67[5]mas/yr |
| Parallax (π) | 1.9414±0.0574 mas[1] |
| Distance | 1,680 ± 50 ly (520 ± 20 pc) |
| Absolute magnitude (MV) | −2.79[6] |
| Orbit[4] | |
| Period (P) | 7829.3±1.4 days |
| Eccentricity (e) | 0.8867±0.0006 |
| Periastronepoch (T) | 54417.21±0.22 |
| Argument of periastron (ω) (secondary) | 250.61±0.20° |
| Semi-amplitude (K1) (primary) | 21.77±0.04 km/s |
| Details | |
| Radius | 45.78+2.89 −3.69[1] R☉ |
| Luminosity | 1,094±43[1] L☉ |
| Surface gravity (log g) | 1.78[7] cgs |
| Temperature | 4,907+210 −149[1] K |
| Metallicity [Fe/H] | +0.04[7] dex |
| Rotational velocity (v sin i) | 6.2[8] km/s |
| Other designations | |
| BD+40° 1346,HD 36891,HIP 26363,SAO 40481 | |
| Database references | |
| SIMBAD | data |
HR 1884 is aspectroscopic binarystar in theconstellationAuriga. The primary is a G typesupergiant star while the secondary is probably a B typemain sequence star.[4]
The possible spectroscopic binary nature of the star was first noted in 1983 by Gilbert Burki andMichel Mayor in a paper on the rate of binaries among supergiant stars.[9] In the same year,William P. Bidelman noted that thestellar spectrum was composite indicating a companion star.[10] Confirmation of spectroscopic binary status and a preliminary orbit was published in 1998 byR. Paul Butler,[11] a much more accurate orbit was published in 2015 by Roger Griffin.[4]
