Thinking on Mars: The Brains of NASA’s Red Planet Rovers

Humans have long depended on machines to explore strange, new worlds; guiding mechanical rovers from millions of miles away, then waiting — and hoping — that the robotic beast carried out its instructions. Spirit and Opportunity, NASA’s twin Mars Exploration Rovers (MER), are no exception to the rule. But while their onboard computers are based on past spacecraft computing systems, engineers have beefed up their memory capacities to handle what is hoped to be a slew of data from Mars despite a serious glitch with the rover, Spirit.