2M1207

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**2M1207**
Observation data Epoch J2000.0
Constellation	Hydra
Right ascension	12^h 07^m 33.4^s
Declination	-39° 32' 54"
Apparent magnitude (V)	13
Distance	173 ly (53 pc)
Spectral type	M8V
Other designations
2MASSW J1207334-393254

2M1207, 2M1207A or 2MASSW J1207334-393254 is a brown dwarf star located in the constellation Hydra; a companion object, 2M1207b, is believed to be one of the first extrasolar planets to be directly imaged, and is the first exoplanet to be discovered in orbit of a brown dwarf.

Located at right ascension 12hr 7min 33.4sec, and declination -39° 32′ 54″ (J2000.0 celestial coordinates), 2M1207 was discovered during the course of the 2MASS infrared sky survey: hence the "2M" in its name, followed by its celestial coordinates. It is roughly 53 parsecs away; with a fairly early (for a brown dwarf) spectral type of M8, it is very young, and a likely member of the TW Hydrae association. Its estimated mass is around 21 Jupiter masses.

In December 2005, American astronomer Eric Mamajek reported a more accurate distance to 2M1207 using the moving cluster method. The new distance (revised downwards from 70 parsecs) results in a fainter luminosity for 2M1207A, and its mass was revised downwards from an original value of 25 Jupiter masses.

[edit] 2M1207b

Main article: 2M1207b

**2M1207b**
Observed position
Extrasolar planet		Lists of extrasolar planets
Observed separation	(d)	41 ± 5 AU
Physical characteristics
Mass	(m)	3.3^+1.5_-1.0 M_J
Radius	(r)	1.5 R_J
Density	(ρ)	? kg/m³
Temperature	(T)	1250 ± 200 K
Discovery information
Discovery date		2004
Discoverer(s)		Chauvin et al.
Detection method		Imaged
Discovery status		Confirmed