UGPS J072227.51-054031.2

UGPS J072227.51-054031.2 (designation often abbreviated to UGPS 0722-05) is a brown dwarf of late T type, located approximately 4.1 parsecs (13 light-years) from Earth.

History of observations

Discovery

The astronomical object was discovered by Philip Lucas at the University of Hertfordshire and announced in 2010. The discovery image was taken on 28 November 2006 by the UKIRT Infrared Deep Sky Survey (UKIDSS) with a recovery image confirming the object's proper motion on 2 March 2010. The reported distance is derived from the current measured parallax of 246 milliarcseconds. The object was initially reported to be at an even closer distance of 2.9 parsecs, which would have placed it among the ten nearest stars to the Sun but later measurements revealed that the object was in fact located at a greater distance than initially thought, at 4.1+0.6
−0.5 parsecs.

Adaptive optics observations

In 2010 Bouy et al. observed UGPS 0722-05 using adaptive optics at the Very Large Telescope. Any companion with H magnitude ≲ 19.4 at separations larger than 50 mas, or with H magnitude ≲ 21.4 at separations larger than 100 mas was not detected.