Insight lander's jammed heat probe starts to turn on Mars again
A key component of NASA’s Insight Mars lander may soon be back in full swing, with a creative maneuver to free the vehicle’s heat probe after it became lodged in the soil now appearing to bear some fruit.
Insight is the first dedicated geological lander to make it to the surface of the Red Planet, and all going to plan, will drill into it further than any scientific instrument in history. It will do this using what is known as “the mole,” a 15-inch-long (40-cm) heat probe that will hammer itself into the soil to a depth of 16 ft (5 m).
This will allow it to measure the thermal conductivity and temperature in the dirt, but things haven’t quite gone to plan so far. As mission control kicked off the hammering phase back in February, the probe only made it around 14 in (35 cm) into the surface before locking up.
The team has been at the drawing board since and in early October settled on a plan to try and salvage the mole. Initially, they suspected hard rocks had ground it to a halt, but images from a camera on the Insight lander’s arm revealed that the probe had encountered an unexpected material called duricrust, cemented soil that is very different to what the probe is designed to burrow through.
So the scientists turned to a tactic they’ve dubbed “pinning,” which means using the lander’s scooping arm to press the probe against the wall of the hole. The hope is that this will offer the self-hammering probe the friction it needs to dig through the duricrust, which is thicker soil than anything ever encountered on a Mars mission.
This solution is being attempted over a number of weeks and there is some promising progress being made. The German Aerospace Center (DLR), which provided the heat probe instrument for NASA, today reported that the pinning tactic is indeed doing the trick (for now).
As mentioned, this duricrust material is not something mission control expected nor planned for, so there is a bit to play out here. If the mole can continue on its way and the mission pans out as hoped, the information it gathers on Mars’ interior could help us better understand how other rocky planets like Mercury, Venus and Earth came to be more than four billion years ago.