HD 79940
Star in the constellation Vela
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HD 79940 is a single[10] star in the southern constellation of Vela. It has the Bayer designation of k Velorum; HD 79940 is the identifier from the Henry Draper Catalogue. This star has a yellow-white hue and is faintly visible to the naked eye as a point light source with an apparent visual magnitude of 4.63.[2] It is located at a distance of approximately 158 light-years from the Sun based on parallax, and is drifting further away with a radial velocity of +6 km/s.[2]
 | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Vela |
| Right ascension | 09h 15m 45.07943s[1] |
| Declination | −37° 24′ 47.3124″[1] |
| Apparent magnitude (V) | 4.63[2] |
| Characteristics | |
| Spectral type | F3/5V[3] or F5III[4][5] |
| B−V color index | 0.473±0.002[2] |
| Astrometry | |
| Radial velocity (Rv) | +5.8±2.8[2] km/s |
| Proper motion (μ) | RA: +14.128[1] mas/yr Dec.: −8.111[1] mas/yr |
| Parallax (π) | 20.5985±0.1895 mas[1] |
| Distance | 158 ± 1 ly (48.5 ± 0.4 pc) |
| Absolute magnitude (MV) | 1.12[2] |
| Details | |
| Mass | 1.36[6] M☉ |
| Radius | 4.35+0.11 −0.19[1] R☉ |
| Luminosity | 28.427±0.305[1] L☉ |
| Surface gravity (log g) | 3.26±0.14[6] cgs |
| Temperature | 6,388+143 −76[1] K |
| Metallicity [Fe/H] | 0.20±0.15[2] dex |
| Rotational velocity (v sin i) | 117.2±5.9[7] km/s |
| Age | 2.76[6] Gyr |
| Other designations | |
| k Vel, CD−36 5505, GJ 339.3, GJ 9293, HD 79940, HIP 45448, HR 3684, SAO 200163, WDS J09158-3725A,[8] k2 Vel[9] | |
| Database references | |
| SIMBAD | data |
There has been some disagreement over the stellar classification of this star. In 1975, S. Maladora found a class of F5III, suggesting an evolved F-type star,[4] matching an earlier (1957) classification by A. de Vaucouleurs.[5] N. Houk assigned it a class of F3/5V in 1979, matching an F-type main-sequence star.[3] It has a high rate of spin with a projected rotational velocity of 117.2±5.9 km/s.[7] This may explain why it was incorrectly classified as a spectroscopic binary in 1972.[10]
There is a faint magnitude 14.50 companion at an angular separation of 11.3″ along a position angle of 126° from the brighter star. This was discovered by T. J. J. See in 1897.[11]