2M 1237+6526

2M 1237+6526

250px T-type brown dwarf 2M 1237+6526 and hypothetical companion.
Observation data Epoch {{{epoch}}}      Equinox
Constellation	Draco
Right ascension	12h 37m 39.20s
Declination	+65° 26′ 14.8″
Characteristics
Spectral type	T6.5V
Apparent magnitude (K)	16.15
Astrometry
Parallax (π)	96.07 ± 4.78 mas
Distance	34 ± 2 ly (10.4 ± 0.5 pc)
Details
Mass	0.035 M☉
Radius	0.11 R☉
Luminosity	6.25×10−6 L☉
Temperature	850 K
Age	≥2-10 billion years
Other designations
2MASS J12373919+6526148, 2MASSI J1237392+652615, 2MASSW J1237392+652615
Database references
SIMBAD	data

2MASS J12373919+6526148 (hereafter 2M 1237+6526) is a brown dwarf object with late spectral type T in the constellation of Draco, nearly 46 light-years away from the Sun, although trigonometric parallax of 96.07±4.78 mas yields distance of 33.9±1.8 light-years (or 10.4±0.5 parsecs). The substellar object could likely host a very low-mass companion (yet undetected but inferred), possibly in planetary regime.

A planetary companion?

Burgasser et al. (2003) have inferred the presence of a low-mass companion orbiting the brown dwarf 2M 1237+6526. Such object would yield a mass between 3 and 12 times that of Jupiter and take nearly 4.56 hours (0.19 days) to revolve around its dim primary. If confirmed it would be the shortest period exoplanet and orbiting the faintest object so far. Accounting very faint luminosity of the primary (6.25/1,000,000th of Sun's luminosity), the water zone is located within 0.0025 Astronomical Units, so putative planet could likely retain great amounts of water] and ammonia. Moreover, both the objects would appear the same size.

The 2M 1237+6526 planetary system

Companion (in order from star)	Mass	Semimajor axis (AU)	Orbital period (days)	Eccentricity	Inclination	Radius
b (unconfirmed)	≥3-12 MJ	≤0.003	≥0.19	?0	—	—