Scientists have finally determined the first steps toward dislodging the Mars InSight lander’s frustratingly stuck heat probe.
NASA successfully planted the InSight lander on Mars late last year, to much fanfare. One of the mission’s major goals was to bury a heat probe 10 to 15 feet below the Martian surface in order to study the planet’s interior, but after only a foot or so, the probe could hammer no farther; at first it seemed like a large rock was blocking the way, but now the team suspects that something about the soil itself is stopping the probe. It’s been stuck in place since February (there’s no way to pull it back up and try a new location, unfortunately). The team has been trying to figure out what to do next.
Scientists operating the InSight lander hope to study the geology of Mars, how its land moves and vibrates, and how heat flows beneath its surface. From the start, the InSight team knew that placing the Heat Flow and Physical Properties Package (HP3) probe would be a challenge. The tool’s digging component is attached to the support structure by a sensor-filled cable; it’s basically a very long thermometer. It digs into the ground via a mechanism that’s more like a hammer than a drill.
A schematic of the HP3. Graphic: DLR
Though we initially reported that rocks could be to blame for the stall, scientists now think that the soil quality differs from initial expectations. The soil doesn’t generate enough friction for the probe to dig deeper, according to a Jet Propulsion Lab release.
InSight’s scientists will begin by lifting the support structure with the lander’s robotic arm in order to get a better view of the drill. This will also allow them to test their first solution: pressing on the ground to increase the friction felt by the drill. The drill can’t be removed from the ground, according to NASA, and if the issue really is with the soil quality, moving the drill wouldn’t fix anything anyway. The lifting of the robotic arm will start later this month.
What’s taken so long? Scientists wanted to make sure their decision wouldn’t make things worse for the probe.
InSight still has a pair of other experiments, the Seismic Experiment for Interior Structure (SEIS) that sits on the ground beside the lander and the Rotation and Interior Structure Experiment (RISE), which sits on top of it. But snags are frustrating, especially when your years-in-the-making experiment is on another planet, much too far away to just fix by hand.