Upsilon1 Centauri
Star in the constellation Centaurus
From Wikipedia, the free encyclopedia
Upsilon1 Centauri is a single[8] star in the southern constellation of Centaurus. Its name is a Bayer designation that is Latinized from υ1 Centauri, and abbreviated Upsilon1 Cen or υ1 Cen. This star has a blue-white hue and is visible to the naked eye with an apparent visual magnitude of +3.87.[1] The distance to this object is approximately 427 light years based on parallax,[2] and is receding with a radial velocity of +9 km/s.[4] It is a member of the Lower Centaurus Crux group of the Scorpius–Centaurus association.[1]
 | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Centaurus[1] |
| Right ascension | 13h 58m 40.75s[2] |
| Declination | −44° 48′ 12.9″[2] |
| Apparent magnitude (V) | +3.87[1] |
| Characteristics | |
| Spectral type | B2 IV/V[3] |
| B−V color index | −0.208±0.011[1] |
| Astrometry | |
| Radial velocity (Rv) | +9.2±1.4[4] km/s |
| Proper motion (μ) | RA: −27.51±0.15 mas/yr[2] Dec.: −22.44±0.13 mas/yr[2] |
| Parallax (π) | 7.63±0.16 mas[2] |
| Distance | 427 ± 9 ly (131 ± 3 pc) |
| Absolute magnitude (MV) | −1.72[1] |
| Details | |
| Mass | 7.9±0.1[5] M☉ |
| Radius | 3.74±0.34[6] R☉ |
| Luminosity | 1,884[1] L☉ |
| Surface gravity (log g) | 4.15±0.07[6] cgs |
| Temperature | 21,411±377[6] K |
| Rotational velocity (v sin i) | 124[4] km/s |
| Age | 13.0±2.0[5] Myr |
| Other designations | |
| υ1 Cen, CD−44°9010, FK5 3112, HD 121790, HIP 68282, HR 5249, SAO 224585[7] | |
| Database references | |
| SIMBAD | data |
The stellar classification of this object is B2 IV/V,[1] matching a massive B-type star with a luminosity class displaying mixed traits of a main sequence and a subgiant star. It is 13[5] million years old and is spinning with a projected rotational velocity of 124 km/s.[4] The star has 7.9[5] times the mass of the Sun and 3.7[6] times the Sun's radius. It is radiating 1,884[1] times the luminosity of the Sun from its photosphere at an effective temperature of 21,411 K.[6]