The number of successful missions to Mars has exploded since the start of the 21st century. As has the number of countries sending them.
Discoveries include more signs that water once flowed on Mars. They also show evidence of thousands of massive ancient volcanic eruptions, plus the remains of ancient hot springs. These suggest that at one time, Mars was a planet with a hot interior. In this way it was much like Earth. Did life as we know it – even tiny microbes – exist on Mars in the distant past? These findings were uncovered by the orbiters, landers, and rovers of the 21st century. They suggest that life was possible.
