By Justin Worland
March 5, 2015

Mars likely had a body of water larger than the Arctic Ocean, according to a new study by NASA scientists.

The size of the Martian ocean is significantly larger than previously thought and provides further evidence that the planet may have once had the ability to support life. The body of water would have been large enough to cover the planet’s entire surface in 450-feet deep water, according to the study published in the journal Science, though it was likely concentrated in smaller areas.

“Our study provides a solid estimate of how much water Mars once had, by determining how much water was lost to space,” said Geronimo Villanueva, a NASA scientist and study author. “With this work, we can better understand the history of water on Mars.”

The scientists analyzed water on Mars today and compared it to water from a 4.5-billion-year-old Mars meteorite to determine how much water was likely lost in the past four billion years.

Still, questions remain about what happened to the large body of water. “With Mars losing that much water, the planet was very likely wet for a longer period of time than was previously thought, suggesting it might have been habitable for longer,” said Michael Mumma, a NASA scientist and study co-author.

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