Using new radar data from ESA’s Mars Express spacecraft, researchers have detected three reservoirs of liquid water trapped below the south polar cap of the Red Planet. An artist’s impression of ESA’s Mars Express spacecraft. Image credit: ESA / ATG Medialab / DLR / FU Berlin / CC BY-SA 3.0 IGO. In 2018, the Mars Express orbiter found evidence of liquid water under the ice in Ultimi Scopuli, a region near the south pole of Mars. To establish...