New Mars study suggests an ocean's worth of water may be hiding beneath the surface. The findings released Monday are based on seismic measurements from NASA’s Mars InSight lander, which detected more than 1,300 marsquakes before shutting down two years ago.
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This water — believed to be seven miles to 12 miles (11.5 kilometers to 20 kilometers) down in the Martian crust — most likely would have seeped from the surface billions of years ago when Mars harbored rivers, lakes and possibly oceans, according to the lead scientist, Vashan Wright of the University of California San Diego’s Scripps Institution of Oceanography.
  

 The study was led by Vashan Wright from the University of California San Diego's Scripps Institution of Oceanography. The findings suggest that if the location of NASA's InSight lander at Elysium Planitia near Mars' equator is representative of the rest of the planet, the underground water would be sufficient to fill a global ocean that is about a mile or so (1 to 2 kilometers) deep.