There’s a new piece of evidence suggesting that Mars was once much wetter than it is today.
— BI: Science (@BI_Science) March 5, 2015
A new NASA study, published in the journal Science, argues that the planet was once home to an ocean’s worth of water about four billion years ago. If that turns out to be true, the amount calculated would have covered nearly half of Mars’ Northern hemisphere.
But it’s still too soon to say for sure. Scientists have long been debating exactly how wet Mars used to be, and this new study definitely isn’t the final word. Most experts agree that the planet had some liquid water at some point, but it’s still unclear how much was really present, and for how long.
So here’s what the new study found — and what it means for our understanding of Mars.