While the Sojourner robot has inched from rock to rock across the Martian landscape over the past few weeks, amazing Earthlings with its close-up view of the red planet, scientists are developing a next generation of bigger and more robust space-ready robots.

During a 45-day field experiment that ended on July 31, a 726-kg (1,600-lb) robotic rover nicknamed “Nomad” practically sprinted more than 215 km (133 miles) around the cold and arid landscape of the Atacama Desert in northern Chile. The robot, which reached a maximum cruising speed of about 1.6 km per hour (1 mph), traveled 32.2 km (20 miles) further than scientists originally had hoped for.