LP 658-2
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Orion[1] |
| Right ascension | 05h 55m 09.53049s[2] |
| Declination | −04° 10′ 07.0653″[2] |
| Apparent magnitude (V) | 14.488[3] |
| Characteristics | |
| Spectral type | DZ11.8[3] |
| Apparent magnitude (B) | 15.49[4] |
| Apparent magnitude (V) | 14.488[3] |
| Apparent magnitude (RKC) | 13.99[5] |
| Apparent magnitude (IKC) | 13.51[5] |
| Apparent magnitude (J) | 13.05 ± 0.03[5] |
| Apparent magnitude (H) | 12.86 ± 0.03[5] |
| Apparent magnitude (KS) | 12.78 ± 0.03[5] |
| B−V color index | 1.0[4][3] |
| Astrometry | |
| Proper motion (μ) | RA: 535.249 mas/yr[2] Dec.: −2,317.011 mas/yr[2] |
| Parallax (π) | 155.2373±0.0175 mas[2] |
| Distance | 21.010 ± 0.002 ly (6.4418 ± 0.0007 pc) |
| Absolute magnitude (MV) | 15.44 ± 0.03[5] |
| Details[3] | |
| From Holberg etal. (2008) | |
| Mass | 0.45±0.01 M☉ |
| Radius | 0.014[3][note 1] R☉ |
| Surface gravity (log g) | 7.80±0.02[3] cgs |
| Temperature | 4,270±70,[3] K |
| Age | 6.42[6][note 2] Gyr |
| Details[5] | |
| From Subasavage etal. (2009) | |
| Mass | 0.80±0.01 M☉ |
| Radius | 0.010 R☉ |
| Surface gravity (log g) | 8.35±0.01 cgs |
| Temperature | 5,180±70 K |
| Age | 6.82±0.02[note 2] Gyr |
| Other designations | |
| HL 4, GJ 223.2, GJ 9193, EGGR 45, G 99-44, G 106-12, LHS 32, LP 658-2, NLTT 15811, WD 0552-041[4] | |
| Database references | |
| SIMBAD | data |
LP 658-2 is a degenerate (white dwarf) star in the constellation of Orion,[4] the single known object in its system. It has an apparent visual magnitude of approximately 14.488.[3]
Distance
[edit | edit source]According to a 2009 paper, it is the eighth closest known white dwarf to the Sun (after Sirius B, Procyon B, van Maanen's star, Gliese 440, 40 Eridani B, Stein 2051 B and GJ 1221).[7] Its trigonometric parallax from the CTIOPI (Cerro Tololo Inter-American Observatory (CTIO) Parallax Investigation) 0.9 m telescope program, published in 2009, is 0.15613 ± 0.00084 arcsec,[5] corresponding to a distance 6.40 ± 0.03 pc, or 20.89 ± 0.11 ly. Also, previous less precise parallax measurements of LP 658-2 present in YPC (Yale Parallax Catalog) and among results of CTIOPI 1.5 m telescope program:
LP 658-2 parallax measurements
| Source | Paper | Parallax, mas | Distance, pc | Distance, ly | Ref. |
|---|---|---|---|---|---|
| YPC | van Altena et al., 1995 | 155.0 ± 2.1 | 6.45 ± 0.09 | 21.04 ± 0.29 | [8] |
| CTIOPI 1.5 m | TSN-14 (Costa et al., 2005) | 156.93 ± 2.67 | 6.37 ± 0.11 | 20.78 ± 0.35 | [9] |
| CTIOPI 0.9 m | TSN-21 (Subasavage et al., 2009) | 156.13 ± 0.84 | 6.40 ± 0.03 | 20.89 ± 0.11 | [5] |
Physical parameters
[edit | edit source]There are two sets of published physical parameters of LP 658-2, significantly differing from each other: one from Holberg et al. 2008 and Sion et al. 2009, the other from Subasavage et al. 2009.
Color
[edit | edit source]Despite it being classified as a "white" dwarf, it appears yellowish white rather than white, due to temperature, cooler than the Sun's and comparable with that of a K-type main sequence star.
Notes
[edit | edit source]References
[edit | edit source]- ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value). Constellation record for this object at VizieR.
- ^ a b c d Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value). Gaia DR3 record for this source at VizieR.
- ^ a b c d e f g h i Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ a b c d Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ a b c d e f g h i 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).
- ^ Table 1 in Sion et al. 2009
- ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value). VizieR entry.
- ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
