HD 83953
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Hydra[1] |
| Right ascension | 09h 41m 17.00785s[2] |
| Declination | −23° 35′ 29.4325″[2] |
| Apparent magnitude (V) | 4.76[1] |
| Characteristics | |
| Spectral type | B5 V[3] |
| B−V color index | −0.117±0.015[1] |
| Astrometry | |
| Radial velocity (Rv) | +16.05±1.5[4] km/s |
| Proper motion (μ) | RA: −29.969[2] mas/yr Dec.: +1.914[2] mas/yr |
| Parallax (π) | 6.5733±0.2851 mas[2] |
| Distance | 500 ± 20 ly (152 ± 7 pc) |
| Absolute magnitude (MV) | −1.19[1] |
| Details | |
| Mass | 4.57±0.08[5] M☉ |
| Radius | 4.00±0.08[6] R☉ |
| Luminosity | 708+60 −55[5] L☉ |
| Surface gravity (log g) | 2.54±0.03[6] cgs |
| Temperature | 15,000±150[6] K |
| Rotational velocity (v sin i) | 315[5][7] km/s |
| Other designations | |
| I Hya, BD−22°2684, HD 83953, HIP 47522, HR 3858, SAO 177840[8] | |
| Database references | |
| SIMBAD | data |
HD 83953 (I Hydrae) is a single,[9] blue-white hued star in the equatorial constellation of Hydra. It is visible to the naked eye, having an apparent visual magnitude of 4.76.[1] Based upon an annual parallax shift of 6.6 mas,[2] the distance to this star is estimated as 500 light years. It is moving further from Earth with a heliocentric radial velocity of +16 km/s.[4]
This is a B-type main-sequence star with a stellar classification of B5 V.[3] It has been known to be a Be star since 1926, when an Hβ emission line was discovered in the stellar spectrum by Mount Wilson Observatory.[10] This energy is coming from a circumstellar envelope of heated gas that has been expelled from the central star and formed a thin orbiting disk.[11] HD 83953 is spinning rapidly with a projected rotational velocity of 315 km/s, giving the star an oblate shape with an equatorial bulge that is 18% larger than the polar radius.[7]
HD 83953 has 4.6[5] times the mass of the Sun and 4.0[6] times the Sun's radius. It is radiating 708[5] times the Sun's luminosity from its photosphere at an effective temperature of 15,000 K.[6]
References
[edit | edit source]- ^ a b c d e Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value). XHIP record for this object at VizieR.
- ^ a b c d e f Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ a b Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ a b Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ a b c d e Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ a b c d e Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ a b Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
