Coldest star so far found – not hotter than a cup of coffee

Astronomers usually classify stellar objects by a spectra going from hotter to cooler, using the letters O, B, A, F, G, K, and M. As observational technology progressed and a myriad of new astronomical findings were made, in the last 15 years alone two new classes  L and T emerged designed to describe ultracool brown dwarfs. A recent scientific finding