Scientists find strong evidence for an underground lake on Mars

Deep below a mile of ice at the Martian south pole lies a lake of liquid water, according to a team of Italian scientists led by Roberto Orosei.

Via NPR:

When Orosei and his colleagues analyzed the data, they saw what looked like a lake of water about 12 miles in diameter and a mile below a surface layer made up of water ice and dust. There are hundreds of this kind of subglacial lake on Earth, mostly in Antarctica.

"After years, literally a couple of years of...discussion, debate, and let's say general head scratching, we really felt confident that any other explanation would fail," Orosei says.

Underground Lake Found On Mars Beneath A Mile of Ice (NPR)