Pluto's Hidden Ocean

摘要

IT'S THE SOLAR SYSTEM EQUIVALENT of leaving a soda can in the freezer too long: Pluto may be cracking apart as its watery insides slowly freeze. Ever since the New Horizons probe buzzed Pluto in July 2015, scientists have been poring over the slow trickle of high-resolution images and data to mine the dwarf planet's secrets. Pluto is more active than scientists dreamed, with mountain chains, roving glaciers and even ice volcanoes. Fissures hundreds of miles long and more than a mile deep hint that something is ripping apart Pluto's outer shell. And as icy as Pluto's surface is, researchers suspect the cause is a freezing ocean underneath.