InSight lander mole on Mars. The mole is a heat probe developed by the German Aerospace Center (DLR) and is part of an instrument called Heat Flow and Physical Properties Package (HP3). The heat probe was designed to burrow into the Martian soil and measure the internal temperature. However, the consistency of the soil meant that the mole was unable to dig three metres deep; the depth needed to measure the heat flowing from the planet. As a result of this, the heat probe was retired from the Insight mission on 14 January 2021. Image taken on the 9 January 2021.