NASA engineers try new plan to resume InSight Lander's heat probe
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InSight Lander.jpg

NASA's InSight Mars lander (File: NASA)

LOS ANGELES, Feb. 21 (Xinhua) -- NASA engineers have a new plan for pushing down on the heat probe of the InSight Lander, which has been stuck at the Martian surface for a year, according to a release of NASA's Jet Propulsion Laboratory (JPL) published on Friday.

The mission team plans to command the scoop on InSight's robotic arm to press down on the "mole," a mini pile driver designed to hammer itself as much as 5 meters down.

They hope that pushing down on the mole's top will keep it from backing out of its hole on Mars, as it did twice in recent months after nearly burying itself.

As part of the heat probe, the mole is a 40-centimeter-long spike equipped with an internal hammering mechanism. While burrowing into the soil, it is designed to drag with it a ribbon-like tether that extends from the spacecraft.

Temperature sensors are embedded along the tether to measure heat coming deep from within the planet's interior to reveal important scientific details about the formation of Mars and all rocky planets, including Earth.

The mole found itself stuck on Feb. 28, 2019, the first day of hammering. The InSight team has since determined that the soil here is different from what has been encountered on other parts of Mars. InSight landed in an area with an unusually thick duricrust, or a layer of cemented soil.

The mole needs friction from soil in order to travel downward; without it, recoil from its self-hammering action causes it to simply bounce in place, according to JPL.

Throughout late February and early March, InSight's arm will be maneuvered into position so that the team can test what happens as the mole briefly hammers.

Meanwhile, the team is also considering using the scoop to move more soil into the hole that has formed around the mole. This could add more pressure and friction, allowing it to finally dig down, according to JPL.

The InSight landed safely on Mars on Nov. 26 of 2018 for a two-year mission to explore the deep interior of the Red Planet.