Upsilon2 Centauri
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Centaurus |
| Right ascension | 14h 01m 43.49909 s |
| Declination | −45° 36′ 12.2767″ |
| Apparent magnitude (V) | +4.33 |
| Characteristics | |
| Spectral type | F7 II/III |
| U−B color index | +0.26 |
| B−V color index | +0.61 |
| Variable type | None |
| Astrometry | |
| Radial velocity (Rv) | −7.8±7.4 km/s |
| Proper motion (μ) | RA: +8.64±1.09 mas/yr Dec.: −16.25±0.88 mas/yr |
| Parallax (π) | 2.57±1.05 mas |
| Distance | approx. 1,300 ly (approx. 400 pc) |
| Absolute magnitude (MV) | −3.51 |
| Orbit | |
| Period (P) | 207.357 d |
| Eccentricity (e) | 0.55 |
| Periastron epoch (T) | 2423880.5 JD |
| Argument of periastron (ω) (secondary) | 88° |
| Semi-amplitude (K1) (primary) | 12.7 km/s |
| Details | |
| Mass | 6.86±0.39 M☉ |
| Luminosity (bolometric) | 3,919 L☉ |
| Surface gravity (log g) | 2.00 cgs |
| Temperature | 6,495 K |
| Rotational velocity (v sin i) | 0.0 km/s |
| Age | 45.9±4.0 Myr |
| Other designations | |
| υ2 Cen, CD−44°9040, GC 18939, HD 122223, HIP 68523, HR 5260, SAO 224621 | |
| Database references | |
| SIMBAD | data |
Upsilon2 Centauri is a binary star system in the southern constellation Centaurus. Its name is a Bayer designation that is Latinized from υ2 Centauri, and abbreviated Upsilon2 Cen or υ2 Cen. This system is visible to the naked eye as a point of light with a combined apparent visual magnitude of +4.33. Based upon an annual parallax shift of 2.57 mas as seen from Earth, this star is located roughly 1,300 light years from the Sun. Relative to its neighbors, the system has a peculiar velocity of 39.2+8.8
−15.2 km/s and it may form a runaway star system.
This is a single-lined spectroscopic binary star system with an orbital period of 207.357 days and an eccentricity of 0.55. The primary component has the spectrum of an evolved F-type giant/bright giant hybrid with a stellar classification of F7 II/III. It is around 46 million years old with 6.9 times the mass of the Sun. The star is radiating 3,919 times the Sun's luminosity from its photosphere at an effective temperature of 6,495 K.