That device? InSight’s self-hammering heat probe dubbed the “mole.” It is designed to measure heat production and flow in the interior of Mars. To accomplish that, the tool has to drill down approximately 16 feet (5 meters) into the Martian regolith. This procedure is presently set to start in January, according to the mole’s principal investigator during a presentation at the annual meeting of the American Geophysical Union.
Tilman Spohn, a planetary scientist at the German space agency, which is known by its German acronym, DLR explained that the heat probe needs to wait its turn because the lander’s supersensitive seismometer and its protective shielding will be deployed first. It will take about a month for that process to happen and is slated to start next week.
If that is successful, the heat probe will be the next to move, with its launch beginning in mid-January. The drilling process will take approximately two months because the probe regularly stops to generate a burst of heat and measure how that heat moves through the rock at its present depth.
However, Spohn is concerned that large rock, about 3 feet (1 m) in diameter, would hinder the probe’s drilling mechanism, which depends on pushing aside dirt. It can push aside or burrow around smaller rocks as it demonstrated during tests in rock chambers here on Earth.
If a blockage does happen, how far the probe has been able to travel will determine how helpful the results are to scientists. According to Spohn, the less the probe penetrates, the worse it will be.
If it’s just 3 feet (1 m) or so deep, the team will need to depend more on intensive modelling. But if it reaches 10 feet (3 m), which should happen around mid-February, the team will be happy— and if it can reach the full depth of 16 feet (5 m) around March 10 or so, that’s even better.
For now, Spohn is happy with InSight’s landing site, which is just as flat and rock-free as scientists were hoping for.
Photo credit: NASA