Software in NASA's twin Mars expedition rovers was updated last week as their missions were extended by up to five more months in a bid to collect confirming evidence of past surface water activity. NASA has provided an additional $15 million in funding to extend the rovers' missions to September.
Spirit completed its primary mission on 5 April, 90 Martian days (or sols) after landing, having driven more than 600m (1,965ft) across the Gusev Crater. The rover began a four-sol stand-down on 8 April to receive the software upload, and rebooted as scheduled on 12 April. On the other side of Mars, on Meridiana Planum, Opportunity began receiving its software update on 10 April, the rover's 75th sol since landing.
The extended mission has seven objectives, with Spirit tasked with reaching Columbia Hills, a range of peaks just over 2km (1.2 miles) from the rover's present position, a trip expected to take two to three months. NASA believes this island of older rock "may hold evidence of an ancient body of water thought to have once filled Gusev Crater". Spirit so far has found only hints of water.
Opportunity, meanwhile, has been tasked with a 750m drive to Endurance crater, to investigate a thicker outcrop of bedrock layers than that examined in Eagle crater, where NASA says the rover found evidence the site was once under flowing water, suggesting the Meridiani region was once a body of salty water.
"Even though the extended mission is approved to September, and the rovers could last longer, they might also stop in their tracks next week. They are operating under extremely hard conditions," says Dr Firouz Naderi, manager of Mars exploration at NASA's Jet Propulsion Laboratory. Dust is accumulating on their solar panels and sunlight will wane as winter approaches.
Source: Flight International
