One last picture for posterity. NASA’s InSight Mars mission is coming to an end. The module took its last selfie on April 24 after 1,211 days on the red planet. Covered in dust and sand, InSight will not be able to continue much longer. NASA is at his bedside in his last, imminent days. Since its landing in 2018, the module has enabled many advances in knowledge of Mars.
InSight takes the pulse and temperature of Mars
When the probe launches on May 5, 2018, it’s a big day for NASA, the National Center for Space Studies (CNES) and their German counterpart (DLR). As part of the Discovery program, InSight (Internal exploration using seismic surveys, geodesy and heat transport, or internal exploration of earthquakes, geodesy and heat currents) should study the structure of Mars for the first time. Until now, we only knew its surface. InSight should make it possible to discover what is hiding below.
For this, the module is equipped with a seismometer, an instrument for measuring the heat flows coming from the heart of the planet (called HP3) and a magnetometer. In short, InSight takes the pulse and temperature of Mars.
Arrived in November 2018 to Mars, its first mission is scheduled to last two years. But as with all modules and probes sent by NASA, its evolution is made to be much more durable. After all, the Voyager 1 probe, launched in September 1977, continues to emit and has led to unexpected discoveries of our universe.
Earthquake and the sound of the wind
Unlike other machines, InSight does not move, some tools are driven into the ground. However, the HP3 has difficulty sinking deep enough. After a few trials, researchers who do not know what is blocking prefer to try to move on.
Quickly, the module allows great progress. InSight detects the first earthquakes on Earth and … the sound of the wind on Mars. In early 2021, the mission will be extended by two years. To “clean” the dust from the solar panels, the articulated arm is reprogrammed to pick up sand and drop it on the panels, where the wind helps remove some of the dirt.
The sound of the wind on Mars
Historical and unexpected data
Today, its heritage is impressive: more than 1,300 earthquakes analyzed – the last of which, on May 4, 2022, had a magnitude of 5 on the Richter scale and caused part of the planet to vibrate for 6 hours -; the most important meteorological data ever; and three geological layers studied (crust, mantle and core).
We now know that the crust is “thinner” than scientists thought (25 to 40 kilometers), and that it is composed of three different layers. The core is molten and larger than expected (a radius of 1,800 km). Thanks to InSight, we know that “light” elements mix with the molten iron, which lowers the melting point. This explains why the core is still molten, even though it has cooled considerably since its formation.
The magnetometer detected residues (or “ghosts”) of electric and magnetic currents. Surprisingly, magnetic signals appear to vary with time, indicating that they are dependent on solar winds interacting with the Martian atmosphere.
All this data has made it possible to better understand the red planet and its ability to perhaps one day contain life.
The dust cover put InSight “to rest”
From now on, InSight shows the weight of those years of meeting the wind and the sand: the gears on its arm grip and no longer allow the “cleaning” of its solar panels, which, covered in dust, can no longer produce enough energy. ‘energy. The only hope would be a very strong wind or a mini-tornado. “We were hoping for such a cleanup, as has been the case several times for Spirit and Opportunity rovers,” explains Bruce Banerdt, head of NASA’s InSight mission. It is still possible, but the energy level is so low that we are now focusing on reproducible scientific data. »
With heavy hearts, the researchers are preparing the module for its final months. His arm will be placed “in the rest position” and most of the instruments will be on standby. Only the seismometer will be in operation for a few hours a day until summer. InSight will still be able to send some data or images occasionally, but the batteries should be empty by December.
In February 2019, NASA sent as a “farewell message” to the unresponsive Mars rover Opportunity, the love song See you, by Billie Holiday. Even though it is almost 60 million kilometers from Earth, InSight will not be turned off in the world alone.