Editing Brown dwarf (section)

=== Gliese 229B and class T ===
The first class "T" brown dwarf was discovered in 1994 by [[Caltech]] astronomers [[Shrinivas Kulkarni]], Tadashi Nakajima, Keith Matthews and [[Rebecca Oppenheimer]],<ref>{{cite web |url=https://hubblesite.org/contents/news-releases/1995/news-1995-48.html |title=Astronomers Announce First Clear Evidence of a Brown Dwarf |website=STScI |access-date=2019-10-23 }}</ref> and [[Johns Hopkins University|Johns Hopkins]] scientists [[Samuel T. Durrance]] and David Golimowski. It was confirmed in 1995 as a [[substellar companion]] to [[Gliese 229]]. Gliese 229b is one of the first two instances of clear evidence for a brown dwarf, along with [[Teide 1]]. Confirmed in 1995, both were identified by the presence of the 670.8&nbsp;nm lithium line. The latter was found to have a temperature and luminosity well below the stellar range.

Its near-infrared spectrum clearly exhibited a methane [[absorption band]] at 2&nbsp;micrometres, a feature that had previously only been observed in the atmospheres of giant planets and that of [[Saturn]]'s moon [[Titan (moon)|Titan]]. Methane absorption is not expected at any temperature of a main-sequence star. This discovery helped to establish yet another spectral class even cooler than '''L'''&nbsp;dwarfs, known as "'''T'''&nbsp;dwarfs", for which Gliese&nbsp;229b is the prototype.