As Mars nears its farthest point from the sun, less light is available to power NASA’s solar-powered Insight Mars lander, a problem compounded by the buildup of dust on the spacecraft’s solar cells. While passing whirlwinds can clear away dust, no such gusts have helped InSight. Engineers have even tried “pulsing” the motors used to deploy the circular arrays, but the effort was not successful.
That’s when Matt Golombek, a member of the InSight science team, came up with a novel solution: using soil scooped up from the surface to effectively “sandblast” the arrays.
To test the idea, InSight’s robot arm scooped up sandy soil near the lander on 22 May and let it trickle down toward the spacecraft’s upper deck while a northeasterly wind blew past at about 6 metres per second (13 mph). Some of the falling sand was blown sideways across the solar panel and wherever the much larger grains impacted, smaller dust particles were dislodged and carried away.
The result was a gain of about 30 watt-hours of energy per martian day. Engineers already were planning to reduce power consumption over the next few months as Mars moves through aphelion, but with slightly cleaner arrays researchers should be able to continue science operations for a few weeks longer than expected.
“We weren’t sure this would work, but we’re delighted that it did,” Golombek said in a JPL release.