Astronomy:DEN 0255−4700
 Artist's impression of an L-dwarf | |
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| 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 |
| Distance | 16.2 ± 0.3 ly (4.97 ± 0.10 pc) |
| Absolute magnitude (MV) | 24.44 |
| Details | |
| Mass | 0.025–0.065[2] M☉ |
| Radius | 0.08–0.1[2] R☉ |
| Temperature | ~1300[2] K |
| Age | 0.3–10[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 | |
| SIMBAD | data |
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.
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
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 "2MUCD 10158 – Brown Dwarf (M<0.08 M☉)". Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-id?Ident=DENIS-P+J0255.0-4700. Retrieved 2009-12-14.
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 Stephens, D. C.; Leggett, S. K.; Cushing, M. C.; Marley, M. S.; Saumon, D.; Geballe, T. R.; Golimowski, D. A.; Fan, X. et al. (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. doi:10.1088/0004-637X/702/1/154. Bibcode: 2009ApJ...702..154S.
- ↑ 3.0 3.1 3.2 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. doi:10.1086/505706. Bibcode: 2006AJ....132.1234C.
- ↑ 4.0 4.1 "Discovery of the Nearest L Dwarf: the Intrinsically Faintest Object at Visual Wavelengths Known Beyond our Solar System". RECONS. http://www.astro.gsu.edu/RECONS/press.2006.08.html. Retrieved 2007-06-17.
- ↑ 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
External links
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