In 2018 a team of Italian scientists announced to the world that there was a lake on Mars. Using satellite radar data, the team detected a very bright area approximately 20 kilometres across located about 1.5 kilometres deep under the ice and dust of the south polar cap.
After analysis, they concluded that the bright area was a subglacial lake filled with liquid water. The discovery raised some fundamental questions.
Was this the only lake hidden beneath the ice on Mars? How could liquid water exist in the extreme cold of the Martian south polar region, where the average surface temperatures are lower than -100 °C?
After acquiring additional satellite data, my colleagues and I have discovered three more distinct “lakes” near the one found in 2018 and confirmed that all four bodies contain liquid water.