A surprising chemical difference between Pluto and Sedna, another dwarf planet in the distant Kuiper Belt, is helping scientists nail down their respective masses, a new study reports. The Kuiper ...

Scientists using a telescope in Hawaii have discovered a never-before-seen dwarf planet lurking within the ring of icy bodies beyond the orbit of Neptune. The small new world -- temporarily named ...

Scientists have used data from a long-retired NASA Dawn spacecraft to solve the mystery surrounding the origins of the ...