KPD 0005+5106 is a helium-rich white dwarf star located 1300 light-years from Earth.[3] As a "pre-white dwarf", the star is believed to still be in the helium-burning phase, just before nuclear fusion finally stops. It is the hottest known white dwarf, with a temperature of 200,000 K.[2]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Cassiopeia |
| Right ascension | 00h 08m 18.17031s |
| Declination | 51° 23′ 16.59837″ |
| Characteristics | |
| Evolutionary stage | Helium-burning pre-white dwarf |
| Astrometry | |
| Proper motion (μ) | RA: 30.043 mas/yr Dec.: -0.727 mas/yr |
| Parallax (π) | 2.4089 ± 0.0355 mas |
| Distance | 1300 ly (398.5818 pc) |
| Details | |
| Mass | 0.64 ± 0.3[1] M☉ |
| Radius | 0.059[1] R☉ |
| Luminosity | 5011.9[1][2] L☉ |
| Surface gravity (log g) | 6.7[1][2] cgs |
| Temperature | 120,000 K; 200,000 ± 20,000[1][2] K |
| Database references | |
| SIMBAD | data |
Possible companion object
editThe star KPD 0005+5106 has been observed to emit high-energy X-rays that regularly increase and descrease in luminosity every 4 hours and 42 minutes. This indicates that the star possibly has a companion orbiting it, either a low-mass star or a planet. The white dwarf pulls material from its companion into a disk around itself, before it slams into its north and south poles. The concentration of material at the poles causes the creation of two bright spots emitting high-energy X-rays.[3]
References
edit- ^ a b c d e Chu, You-Hua; Toala, Jesus A.; Guerrero, Martin A.; Bauer, Florian; Bilikova, Jana; Gruendl, Robert A. (2021-04-01). "Hard X-ray Emission Associated with White Dwarfs. IV. Signs of Accretion from Sub-stellar Companions". The Astrophysical Journal. 910 (2): 119. arXiv:2102.05035. Bibcode:2021ApJ...910..119C. doi:10.3847/1538-4357/abe5a5. ISSN 0004-637X.
- ^ a b c d Wassermann, D.; Werner, K.; Rauch, T.; Kruk, J. W. (2010-12-01). "Metal abundances in the hottest known DO white dwarf (KPD 0005+5106)". Astronomy & Astrophysics. 524: A9. Bibcode:2010A&A...524A...9W. doi:10.1051/0004-6361/201015007. hdl:2060/20110020824. ISSN 0004-6361. S2CID 121234030.
- ^ a b "Chandra :: Photo Album :: KPD 0005+5106 :: November 22, 2021". chandra.si.edu. Retrieved 2023-02-13.