DENIS J081730.0−615520
Location of DENIS J081730.0−615520 in the constellation Carina | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Carina |
| Right ascension | 08h 17m 29.99888s |
| Declination | −61° 55′ 15.6586″ |
| Characteristics | |
| Spectral type | T6 |
| Apparent magnitude (J) | 13.613±0.024 |
| J−H color index | 0.087 ± 0.039 |
| J−K color index | 0.093 ± 0.049 |
| Astrometry | |
| Radial velocity (Rv) | 6.1 ± 0.5 km/s |
| Proper motion (μ) | RA: −156.451(507) mas/yr Dec.: 1,099.366(503) mas/yr |
| Parallax (π) | 191.8362±0.4186 mas |
| Distance | 17.00 ± 0.04 ly (5.21 ± 0.01 pc) |
| Details | |
| Radius | 0.94±0.16 RJup |
| Surface gravity (log g) | 5.0 ± 0.1 cgs |
| Temperature | 1004±91 K |
| Rotation | 2.8±0.2 hours |
| Rotational velocity (v sin i) | 22.5 ± 0.9 km/s |
| Age | 1 Gyr |
| Other designations | |
| DENIS J081730.0−615520 2MASS J08173001-6155158 WISEPA J081729.74−615504.1 | |
| Database references | |
| SIMBAD | data |
DENIS J081730.0−615520 (also known as 2MASS 08173001−6155158) is a T-type brown dwarf 17 light-years (5.2 parsecs) away in the constellation Carina. It was discovered by Etienne Artigau and his colleagues in April 2010. The brown dwarf belongs to the T6 spectral class, with a photosphere temperature of about 1000 K. It has a mass of about 15 MJ (Jupiter masses) or about 1.5% the mass of the Sun.
DENIS J081730.0-615520 is the fourth-nearest isolated T dwarf to the Sun (after UGPS J0722−0540, WISE 1741+2553, and WISE 1506+7027) and the eighth-nearest (also after Luhman 16B, ε Indi Bab and SCR 1845-6357B) if one takes into account T dwarfs in multiple star systems. It is also the brightest T dwarf in the sky (in the J-band); it had been missed before due to its proximity to the galactic plane.
DENIS J081730.0−615520 was observed with Gemini South. This spectrum did result to the first detection of molecular hydrogen (H2) and the first detection of hydrogen sulfide (H2S) in an extrasolar atmosphere. Other molecules detected in the atmosphere of this brown dwarf are methane (CH4), water vapor (H2O), carbon monoxide (CO) and ammonia (NH3). The detection of H2 indicates that the atmosphere of DENIS J081730.0−615520 is almost dust-free.