Rolling, hopping robots explore Earthly analogs of distant planets

Before we send any planet-trotting robot to explore the landscape of Mars or Venus, we need to test it here on Earth. Two such robotic platforms being developed for future missions are undergoing testing at European Space Agency facilities: one that rolls, and one that hops.
The rolling one is actually on the books to head to the Red Planet as part of the ESA’sMars 2020 program. It’s just wrapped a week of testing in the Spanish desert, just one of many Mars analogs space programs us