Chi Puppis
Star in the constellation Puppis
From Wikipedia, the free encyclopedia
χ Puppis, Latinised as Chi Puppis, is a single[11] star in the southern constellation of Puppis. It has a white hue and is faintly visible to the eye at night with an apparent visual magnitude of 4.79.[2] The star is located at a distance of approximately 1,800 light years from the Sun based on parallax,[1] and is drifting further away with a radial velocity of +30 km/s.[7] O. J. Eggen listed this star as a member of the Hyades Stream based on its space motion.[12]
 | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Puppis |
| Right ascension | 07h 57m 40.10678s[1] |
| Declination | −30° 20′ 04.4491″[1] |
| Apparent magnitude (V) | 4.79[2] |
| Characteristics | |
| Spectral type | A5 II[3] or A7 III[4] or A2 Vv[5] |
| U−B color index | +0.16[2] |
| B−V color index | +0.151±0.012[6] |
| Astrometry | |
| Radial velocity (Rv) | +30.0±0.5[7] km/s |
| Proper motion (μ) | RA: −8.643[1] mas/yr Dec.: +6.055[1] mas/yr |
| Parallax (π) | 1.7957±0.1890 mas[1] |
| Distance | approx. 1,800 ly (approx. 560 pc) |
| Absolute magnitude (MV) | −3.07[6] |
| Details | |
| Radius | 30.39+1.53 −1.70[1] R☉ |
| Luminosity | 3,116±374[1] L☉ |
| Surface gravity (log g) | 2.17[8] cgs |
| Temperature | 7,823+229 −190[1] K |
| Rotational velocity (v sin i) | 39.2±0.3[9] km/s |
| Other designations | |
| chi Pup, NSV 3830, CD−29°5236, FK5 1210, GC 10774, HD 65456, HIP 38901, HR 3113, SAO 198636, GSC 07120-02422[10] | |
| Database references | |
| SIMBAD | data |
There has been some disagreement as to the stellar classification of Chi Puppis. In 1962, W. Buscombe classified it as A2Vvar,[13] matching a variable A-type main-sequence star. However, P. S. Conti in 1965 considered that to be a misclassification on the basis of its B-V color index. He considers it of later type A5.[14] In their study of the nearby open cluster NGC 2483, M. P. Fitzgerald and A. F. J. Moffat used the same class, A2Vv.[5] In 1979, Nancy Houk assigned it to class A7 III,[4] indicating it may be an A-type giant star. Finally, R. O. Gray and associates found a class of A5 II,[3] matching a bright giant.
In his star atlas Neue Uranometrie, Friedrich Wilhelm Argelander labelled this star as χ Argo. It was probably labelled as χ by Bayer in the original Uranometria, although Bayer's chart is somewhat fanciful. Nicolas-Louis de Lacaille changed Bayer's designations in Argo Navis and applied χ to the star now called χ Carinae.[15]