Curiosity rover finds tantalizing hints that Mars could once have been habitable
Despite its freezing temperatures, thin atmosphere, and lack of surface water today, scientists believe that Mars could once have been capable of supporting life. No one knows whether life ever did develop there (though there is almost certainly nothing alive there now), but finding out if our neighboring planet ever did host microbial life is one of the great questions in astronomy today. Now, scientists are one step closer to answering that question....