'Frozen Lake' on Pluto May Point to a Warmer Time

NASA's New Horizons spacecraft has spotted evidence that liquids might have once flowed across the dwarf planet that stole everyone's heart. The evidence comes in the form of a frozen lake that researchers think once harbored liquid nitrogen. New Horizons spotted the lake during its July flyby of the dwarf planet, which also gave observers the iconic view of the broad, heart-shaped region on Pluto's surface that is nicknamed Tombaugh Regio.