V Centauri
Variable star in the constellation Centaurus
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V Centauri (V Cen) is a Classical Cepheid variable, a type of variable star, in the constellation Centaurus. It is approximately 2,350 light-years (720 parsecs) away based on parallax.
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Centaurus |
| Right ascension | 14h 32m 33.0833s[2] |
| Declination | −56° 53′ 15.774″[2] |
| Apparent magnitude (V) | 6.42 - 7.22[3] |
| Characteristics | |
| Spectral type | F5 Ib/II[4] |
| B−V color index | 0.87[5] |
| Variable type | Classical Cepheid[3] |
| Astrometry | |
| Radial velocity (Rv) | −18.90 ± 1.4[6] km/s |
| Proper motion (μ) | RA: −6.697[2] mas/yr Dec.: −7.068[2] mas/yr |
| Parallax (π) | 1.3898±0.0221 mas[2] |
| Distance | 2,350 ± 40 ly (720 ± 10 pc) |
| Details | |
| Mass | 4.3[7] M☉ |
| Radius | 40[2] R☉ |
| Luminosity | 1,657[8] L☉ |
| Surface gravity (log g) | 1.89[2] cgs |
| Temperature | 5,500[8] K |
| Metallicity [Fe/H] | +0.12[9] dex |
| Age | 103[10] Myr |
| Other designations | |
| V Cen, CD−56°5479, HD 127297, HIP 71116, HR 5421, SAO 241777[5] | |
| Database references | |
| SIMBAD | data |
Alexander W. Roberts discovered this star in 1894, and from 267 visual observations he determined is period of variation.[11] V Centauri varies regularly between visual magnitudes 6.42 and 7.22 every 5.5 days. It is classified as a Cepheid variable on the basis of its light variations, with the brightness increase from minimum to maximum taking only a third of the time of the decrease from maximum to minimum. Cepheids are pulsating variable stars and V Centauri expands and contracts over its pulsation cycle as well as changing temperature.[3]
According to the South African Astronomical Observatory, the chemical composition was derived as being high in sodium (Na) and aluminium (Al) and low in magnesium (Mg).[12] Following a normal composition for a Cepheid star, V Cen does not have any unusual characteristics. V Centauri's composition was observed alongside six other Classical Cepheid variable stars with the support of Russian, Chilean, and Ukrainian observatories.[12]