Most of Mars’ missing water may lurk in its crust
That may explain why so little H2O is seen escaping into space to dry out the Red Planet
![illustration of mars if it had surface water](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2021/03/031521_mt_mars-water_feat.jpg?fit=1030%2C580&ssl=1)
Billions of years ago, Mars was a watery world (illustrated) like Earth. But over time, much of the Red Planet’s water has gotten locked up inside its crust, a new study shows.
GSFC/NASA