In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.

In 1998, astronomers discovered Cha H-alpha 1, the first one of these objects to emit X-Rays. They can be difficult to identify because their diameters are often comparable to those of massive planets, although their density is much greater. Most of the known ones have been identified through the detection of lithium, which is not typically found in their larger counterparts. The first verified one, Teide 1, was found in 1995, fitting the classification of having a mass greater than 12 times that of Jupiter, the minimum mass for performing deuterium fusion. FTP, name these non-luminous sub-stellar objects that do not have a large enough mass to fuse hydrogen into helium, often known as "failed stars. "
Science