DEN 0255−4700

DENIS 0255−4700 is an extremely faint brown dwarf approximately 16 light years from the Solar System in the southern constellation of Eridanus.[1][4] It is the closest isolated L brown dwarf (no undiscovered L dwarves are expected to be closer), and only after the binary Luhman 16. It is also the faintest brown dwarf (with the absolute magnitude of MV=24.44) having measured visible magnitude.[3] A number of nearer T and Y-type dwarfs are known, specifically WISE 0855−0714, Epsilon Indi B and C, SCR 1845-6357 B, DEN 1048−3956, and UPGS 0722−05.

DENIS 0255−4700

Artist's impression of an L-dwarf
Observation data
Epoch J2000      Equinox J2000
Constellation Eridanus
Right ascension  02h 55m 03.579s[1]
Declination −47° 00′ 50.99″[1]
Characteristics
Spectral type L8/L9[2]
Apparent magnitude (V) ~22.9[1]
Apparent magnitude (R) ~20.1[1]
Apparent magnitude (I) ~17.2[1]
Apparent magnitude (J) ~13.2[1]
Astrometry
Proper motion (μ) RA: 1053 ± 11[1] mas/yr
Dec.: −547 ± 6[1] mas/yr
Parallax (π)201.37 ± 3.89[3] mas
Distance16.2 ± 0.3 ly
(4.97 ± 0.10 pc)
Absolute magnitude (MV)24.44
Details
Mass0.025–0.065[2] M☉
Radius0.08–0.1[2] R☉
Temperature~1300[2] K
Age0.3–10[2] Gyr
Other designations
2MUCD 10158,
DENIS-P J025503.3−470049,
2MASS J02550357−4700509,
DENIS-P J025503.5−470050,
DENIS-P J0255.0−4700,
2MASSI 0255035−470050
Database references
SIMBADdata

History of observations

DENIS 0255−4700 was identified for the first time as a probable nearby object in 1999.[4] Its proximity to the Solar System was established by the RECONS group in 2006 when its trigonometric parallax was measured.[3] DENIS 0255-4700 has a relatively small tangential velocity of 27.0 ± 0.5 km/s.[2]

Properties

The photospheric temperature of DENIS 0255−4700 is estimated at about 1300 K.[2] Its atmosphere in addition to hydrogen and helium contains water vapor, methane and possibly ammonia.[5] The mass of DENIS 0255−4700 lies in the range from 25 to 65 Jupiter masses corresponding to the age range from 0.3 to 10 billion years.[2]

See also

References
  1. "2MUCD 10158 – Brown Dwarf (M<0.08 M☉)". Centre de données astronomiques de Strasbourg. Retrieved 2009-12-14.
  2. Stephens, D. C.; Leggett, S. K.; Cushing, M. C.; Marley, M. S.; Saumon, D.; Geballe, T. R.; Golimowski, D. A.; Fan, X.; Noll, K. S. (2009). "The 0.8–14.5 μm Spectra of Mid-L to Mid-T Dwarfs: Diagnostics of Effective Temperature, Grain Sedimentation, Gas Transport, and Surface Gravity". The Astrophysical Journal. 702 (1): 154–170. arXiv:0906.2991. Bibcode:2009ApJ...702..154S. doi:10.1088/0004-637X/702/1/154.
  3. Costa, E.; Méndez, R. A.; Jao, W. -C.; Henry, T. J.; Subasavage, J. P.; Ianna, P. A. (2006). "The Solar Neighborhood. XVI. Parallaxes from CTIOPI: Final Results from the 1.5 m Telescope Program". The Astronomical Journal. 132 (3): 1234. Bibcode:2006AJ....132.1234C. CiteSeerX 10.1.1.622.2310. doi:10.1086/505706.
  4. "Discovery of the Nearest L Dwarf: the Intrinsically Faintest Object at Visual Wavelengths Known Beyond our Solar System". RECONS. Retrieved 2007-06-17.
  5. Cushing, Michael C. (2006). "Spitzer Space Telescope Observations of M, L, and T Dwarfs". ASP Conference Series. 357: 66–67. Bibcode:2006ASPC..357...66C.

Notes


    This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.