HD 99015
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| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Chamaeleon[1] |
| Right ascension | 11h 21m 56.89166s[2] |
| Declination | −77° 36′ 30.1275″[2] |
| Apparent magnitude (V) | 6.42±0.01[3] |
| Characteristics | |
| Evolutionary stage | main sequence[2] |
| Spectral type | A5 V[4] |
| U−B color index | +0.11[5] |
| B−V color index | +0.20[5] |
| Astrometry | |
| Radial velocity (Rv) | −5.9±2.5[6] km/s |
| Proper motion (μ) | RA: −79.623 mas/yr[2] Dec.: −8.231 mas/yr[2] |
| Parallax (π) | 13.3992±0.0202 mas[2] |
| Distance | 243.4 ± 0.4 ly (74.6 ± 0.1 pc) |
| Absolute magnitude (MV) | +2.08[1] |
| Details | |
| Mass | 1.87±0.06[7] M☉ |
| Radius | 1.83±0.09[8] R☉ |
| Luminosity | 12.0+0.3 −0.2[2] L☉ |
| Surface gravity (log g) | 4.2±0.1[9] cgs |
| Temperature | 7,859±124[9] K |
| Metallicity [Fe/H] | +0.15[10] dex |
| Age | 854[11] Myr |
| Other designations | |
| 31 G. Chamaeleontis[12], CD−76°495, CPD−76°662, GC 15628, HD 99015, HIP 55497, HR 4397, SAO 256832[13] | |
| Database references | |
| SIMBAD | data |
HD 99015, also known as HR 4397 or rarely 31 G. Chamaeleontis, is a solitary white-hued star located in the southern circumpolar constellation Chamaeleon. It has an apparent magnitude of 6.42,[3] placing it near the limit for naked eye visibility even in ideal conditions. The object is located relatively close at a distance of 243 light years[2] and is drifting closer with a somewhat constrained heliocentric radial velocity of −5.9 km/s.[6] At its current distance, HD 99015's brightness is diminished by 0.31 magnitudes due to interstellar dust.[14] It has an absolute magnitude of +2.08.[1]
This is an ordinary A-type main-sequence star with a stellar classification of A5 V.[4] However, Nancy Houk and A. P. Cowley gave a class of A5 III/IV,[15] indicating that it is instead an evolved A-type star with the luminosity class of a subgiant and giant star. It has 1.87 times the mass of the Sun[7] and 1.83 times the solar radius.[8] It radiates 12 times the luminosity of the Sun[2] from its photosphere at an effective temperature of 7,859 K.[9] HD 99015 is somewhat metal enriched ([Fe/H] = +0.15[10]) and is estimated to be 854 million years old.[11]
