Take a sip, future Mars-goers. Beneath a New Mexico–sized portion of the Red Planet’s cracked surface, lays a large volume of water ice, The New York Times reports. Those visible scalloped crack patterns have long been a suspected indicator of ice shifting below the ground; it’s something seen on Earth rather frequently in the Canadian Arctic. Scientists used radar readings from NASA’s Mars Reconnaissance Orbiter to estimate ice thickness in the region to between 80 to 170 meters thick, as published recently in the journal Geophysical Research Letters. The ice, which the lead researcher suggests built up from snowfall during one of the planet’s ice ages, is likely at least 50% frozen water with dirt, rocks, and hollow pockets intermixed. With a little manipulation, ice from the reservoir could be used as a source of martian drinking water.