NASA’s Mars rover Opportunity seems to have stumbled into something akin to a car wash that has left its solar panels much cleaner than those of its twin rover, Spirit. A Martian car wash would account for a series of unexpected boosts in the electrical power produced by Opportunity’s solar panels.
The rovers landed on Mars in January with solar cells capable of providing more than 900 watt-hours of electricity per day. Spirit’s output has dropped to about 400 watt-hours, partly because Martian dust has caked its solar panels. Opportunity’s output also declined at first – to around 500 watt-hours…
