Mars was habitable longer, more recently than thought
Warmer, wetter conditions lasted until 3.5 billion years ago
![](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2013/12/ag_Mars_pia17595figA_feat.jpg?fit=860%2C460&ssl=1)
WETTER ONCE Curiosity’s Mast Camera surveyed Mars’ Yellowknife Bay formation, a region that could have supported liquid water for millions of years. The foothills of Mount Sharp, Curiosity’s primary destination, are at upper left.
JPL-Caltech/NASA, MSSS