... Photos . ... Supernova showered Earth with radioactive debris . ... Record-breaking photo reveals a planet-sized object as cool as Earth . Astronomers classify this object as a brown dwarf, an object that formed just like a star out of a massive cloud of dust and gas. ... Burgasser said. т??Brown dwarfs with Earth-like temperatures allow us to refine theories about the atmospheres of objects outside our solar system that have comparatively cool atmospheres like that of our own planet.т?? ...