Researchers at the Palomar Observatory, Caltech, USA, have recently reported the coolest brown dwarf with the lowest mass. Brown dwarves are star-like objects which have a mass less than 0.08 times that of the sun and are unable to sustain the thermonuclear reactions in their interiors.

Most of their gravitational energy is radiated away relatively rapidly, leaving behind a very dim object. From observations of about 100 stars in a carefully determined sample, scientists have discovered a probable companion of the star GI229, which is a brown dwarf.