Coldest Brown dwarf star

A new brown dwarf star has been discovered that is the coldest yet. Brown dwarf stars are usually less than 70 time Jupiter's mass. Normal stars spend most of their time burning hydrogen and maintaining a standard internal temperature. However, brown dwarfs usually spend their time getting colder. Brown dwarf stars were first discovered in 1995 and many more have been discovered since then.
This brown dwarf star, CFBDS J005910.83-011401.3, is about 40 light years away from our solar system. It was discovered by an international team that used the Canadian France Hawaii telescope, the Gemini North telescope (both of which reside in Hawaii), and European Southern Observatory telescope in Chile.l
What are brown dwarf stars? Well, they are similar to very large planets but they have their differences. One for example, is that while water is condensed into ice on most giant planets, it is always gaseous on brown dwarf stars. Ammonia has never been found in their atmospheres either, while it makes up a large amount of Jupiter's atmosphere. Similarities include clouds of dust and aerosol, along with large amounts of methane in the atmospheres.

However, this newly discovered brown dwarf has different properties than either of the existing classes of brown dwarf stars: L and T. L dwarfs have temperatures from 1,200 - 2000 Celsius while T dwarfs have less than 1,200 Celsius.
This new dwarf has even lower temperatures and even has ammonia. In this manner, it is much more like a humongous planet than any other discovery. Researchers now propose that they call this new class Y dwarfs.
Scientists hope to use these discoveries to learn more about planetary formation and extrasolar planets, as planets are usually bound to a star and are harder to observe than brown dwarf stars that are not attached.