2MASS J05325346+8246465
Appearance
Observation data Epoch J2000[1] Equinox J2000[1] | |
---|---|
Constellation | Camelopardalis |
Right ascension | 05h 32m 53.46s[1] |
Declination | +82° 46′ 46.5″[1] |
Characteristics | |
Spectral type | L7[1] |
Astrometry | |
Parallax (π) | 40.2369 ± 0.6389 mas[1] |
Distance | 81 ± 1 ly (24.9 ± 0.4 pc) |
Details | |
Mass | 0.077–0.085[citation needed] M☉ |
Metallicity | 0.1–0.01[2] |
Age | 10–15[citation needed] Gyr |
Other designations | |
Database references | |
SIMBAD | data |
2MASS 0532+8246 (full designation 2MASS J05325346+8246465) is possibly the first brown dwarf observed in the galactic halo of the Milky Way, and the first known substellar subdwarf star.[3][2] It was discovered from Two Micron All-Sky Survey data, and verified by observations at Palomar Observatory and W. M. Keck Observatory.[2] It has a low metallicity, which indicates it is an old star.[2] With an age of 12.5 billion years, it is the oldest known brown dwarf star.[citation needed]
The mass and temperature of 2MASS 0532+8246 makes it a rare object in stellar-substellar gap between conventional stars and brown dwarfs.[4]
References
- ^ a b c d e f g "2MASS J05325346+8246465 -- Brown Dwarf (M<0.08solMass)". SIMBAD. Centre de Données astronomiques de Strasbourg. Retrieved 2018-12-04.
- ^ a b c d Burgasser, Adam J. et al. (2003) The First Substellar Subdwarf? Discovery of a Metal-Poor L Dwarf with Halo Kinematics. The Astrophysical Journal, 592(2) 1186.
- ^ Faherty, Jacqueline K.; Burgasser, Adam J.; Walter, Frederick M.; Van der Bliek, Nicole; Shara, Michael M.; Cruz, Kelle L.; West, Andrew A.; Vrba, Frederick J.; Anglada-Escud, Guillem (2012). "The Brown Dwarf Kinematics Project (BDKP). III. Parallaxes for 70 Ultracool Dwarfs". The Astrophysical Journal. 752 (1): 56. arXiv:1203.5543. Bibcode:2012ApJ...752...56F. doi:10.1088/0004-637X/752/1/56. S2CID 18160586.
- ^ Zhang 张曾华, Z. H.; Homeier, D.; Pinfield, D. J.; Lodieu, N.; Jones, H. R. A.; Allard, F.; Pavlenko, Ya. V. (2017), "Primeval very low-mass stars and brown dwarfs – II. The most metal-poor substellar object", Monthly Notices of the Royal Astronomical Society, 468: 261–271, arXiv:1702.02001, doi:10.1093/mnras/stx350, S2CID 54847595
{{citation}}
: CS1 maint: unflagged free DOI (link)
External links