A team of researchers from the United States Geological Survey revealed their findings on Thursday in the academic journal Science.

Although scientists have previously known of ice on Mars, the new discovery shows just how big the ice sheets can get, with some extending 300 feet below Mars’s surface, the report said. The sheer size of the ice sheets could help scientists better understand the history of Mars and its climate, NASA said.

“It’s like having one of those ant farms where you can see through the glass on the side to learn about what’s usually hidden beneath the ground,” the paper’s co-author Shane Byrne said in a statement.

What secrets are buried in Martian ice? @NASA’s Mars Reconnaissance Orbiter reveals eight sites that could provide crucial resources for future astronauts: https://t.co/C2geNTjKc7 #ThursdayThoughts pic.twitter.com/NMQUXhz056

— NASA JPL (@NASAJPL) January 11, 2018

Additionally, the scientists discovered the ice sheets in eight difference places that could be future sources of water for astronauts. These locations were not found on Mars’ polar ice caps, where “hostile conditions” would prevent astronauts from scavenging the Martian ice, but in more friendly areas, NASA said.

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“Astronauts could essentially just go there with a bucket and a shovel and get all the water they need,” Byrne added.

The scientists also learned that the ice, which was exposed due to erosion on hillside cliffs, contains little rock and dust particles, meaning it’s “relatively pure water ice” that could be used be “readily accessible to future exploration missions,” the Geological Survey agency said.

The new Mars ice imagery were captured by NASA’s Mars Reconnaissance Orbiter, and subsequently studied by the scientists.