
How Did Pluto Get Its 'Whale'?
Some scientists believe Pluto's red "whale"-shaped region is the mark of a giant impact — the same one that produced Pluto's huge moon Charon.
Pluto, once considered the ninth and most distant planet from the sun, is now the largest known dwarf planet in the solar system. It is also one of the largest known members of the Kuiper Belt, a shadowy zone beyond the orbit of Neptune thought to be populated by hundreds of thousands of rocky, icy bodies each larger than 62 miles (100 kilometers) across, along with 1 trillion or more comets.