Beta Chamaeleontis
Star in the constellation Chamaeleon
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Beta Chamaeleontis, Latinized from β Chamaeleontis, is the third-brightest star in the southern constellation of Chamaeleon. A solitary,[13] suspected variable star, it is visible to the naked eye as a faint blue-white point of light with an apparent visual magnitude that has been measured ranging between 4.24 and 4.30.[3] Parallax measurements yield a distance estimate of 298 light years from the Sun, and it is drifting further away with a radial velocity of +23 km/s.[7]
 | |
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Chamaeleon |
| Right ascension | 12h 18m 20.82459s[1] |
| Declination | −79° 18′ 44.0710″[1] |
| Apparent magnitude (V) | 4.24[2] (4.24 to 4.30)[3] |
| Characteristics | |
| Evolutionary stage | main sequence[4] |
| Spectral type | B4 V[5] |
| U−B color index | −0.52[2] |
| B−V color index | −0.13[2] |
| R−I color index | −0.10[6] |
| Astrometry | |
| Radial velocity (Rv) | +23.0[7] km/s |
| Proper motion (μ) | RA: −37.97[1] mas/yr Dec.: +11.15[1] mas/yr |
| Parallax (π) | 10.93±0.15 mas[1] |
| Distance | 298 ± 4 ly (91 ± 1 pc) |
| Absolute magnitude (MV) | −0.57[8] |
| Details | |
| Mass | 5.0±0.1[9] M☉ |
| Radius | 2.84±0.13[10] R☉ |
| Luminosity | 212[11] L☉ |
| Surface gravity (log g) | 4.03±0.05[10] cgs |
| Temperature | 14,495±157[10] K |
| Rotational velocity (v sin i) | 255[6] km/s |
| Age | 22.7±7.2[9] Myr |
| Other designations | |
| β Cha, CD−78°495, CPD−78°741, FK5 459, GC 16775, HD 106911, HIP 60000, HR 4674, SAO 256924, PPM 371459[12] | |
| Database references | |
| SIMBAD | data |
This is a B-type main-sequence star with a stellar classification of B4 V[5] that is generating energy through core hydrogen fusion. It has been catalogued both as a Be star[2] and a normal star.[14] This object is about 23[9] million years old with a high projected rotational velocity of 255 km/s.[6] The rapid rotation is creating an equatorial bulge that is 12% larger than the polar radius.[15] The star has five[9] times the mass of the Sun and 2.8[10] times the Sun's radius. It is radiating 212[11] times the luminosity of the Sun from its photosphere at an effective temperature of 14,495 K.[10]