... Star Atlas . ... stars . ... Astronomers find Rosetta stone for T-dwarf stars . A star system with a cool methane-rich T-dwarf star and a dying white dwarf stellar remnant in orbit around each other gives scientists the first good handle on T-dwarfsт?? mass and age. ... An international team of astronomers has discovered a unique and exotic star system with a cool methane-rich, or T-dwarf star, and a dying white dwarf stellar remnant in orbit around each other. ... Atlas of the Stars . ...