NASA gives up on the "mole" portion of the InSight lander mission

One of the mission experiments aboard the InSight Lander that scientists worked to deploy on Mars was the heat probe known as the "mole" developed by the German Aerospace Center. The heat probe has been unable to gain the friction it needs to dig into the Martian soil. While the overall InSight mission has been granted an extension, the mole has ended its portion of the mission.The mole was to burrow into the Martian surface to measure the planet's internal temperature and provide details about the interior heat engine driving the evolution and geology of the Red Planet. The martian soil had an unexpected tendency to clump and prevented the mole from getting the friction it needed to hammer itself to the depth required for the mission.

Only the top two or three centimeters of the mole were able to dig into the surface of Mars. NASA says its last attempt with the mole was to use the scoop on the robotic arm of the lander to put soil on the probe and tamp it down to provide added friction. After adding the soil, the probe conducted 500 additional hammer strokes on January 9 with no additional progress.

The failure marked the end of the efforts for the team on that particular part of the mission. For that experiment to function, sensors aboard the mole had to be at least 10 feet deep. NASA does say that it's learned a lot from the mole and its inability to dig that will benefit future missions that want to dig into the surface of Mars.

Scientists will continue to puzzle over the Martian soil's unexpected properties near InSight and how it differed from other soil samples previously seen during Mars missions. The soil near InSight proved very different from what was seen on previous missions. NASA recently extended InSight's mission for an additional two years.