But the data collected will remain used by scientists around the world for many years to continue to improve our understanding of planet formation, NASA said in making the announcement Tuesday.

Notably equipped with an ultra-sensitive seismometer, InSight has recorded more than 1,300 "Marsquakes", including one of magnitude 5 just two weeks ago, the biggest so far.

A nice reward just before the end clap: around the month of July, the seismometer will be turned off.

The energy level of the probe will then be checked about once a day, and a few pictures may still be taken.

Then by the end of 2022, the mission will be completely stopped.

The reason: the accumulation, over the months, of Martian dust on the two solar panels, each measuring about 2.2 meters wide.

InSight, which already only works with a tenth of the energy it enjoyed each day at the start, will therefore soon find its batteries flat.

The speed of accumulation of the dust turned out to correspond more or less to what had been estimated in advance by the NASA teams.

About a year ago, they had carried out a somewhat surprising cleaning, using dust itself.

The robot arm had dug into the ground, and gently dropped Martian soil above the robot.

A part was thus carried by the wind on the solar panels, releasing a little their surface.

This technique had made it possible to prolong the mission.

Why not have something on board to wash the panels directly?

For questions of costs, answered at a press conference Tuesday Bruce Banerdt, of the Jet Propulsion Laboratory of NASA.

Such a mechanism would indeed have encroached on the budget allocated to scientific instruments.

"Treasure of Information"

InSight, one of the four robots currently on the red planet - along with the American rovers Perseverance and Curiosity, and the Chinese Zhurong - arrived on Mars in November 2018.

Illustrative photo provided by NASA of the InSight robot - NASA/AFP/Archives

Its seismometer, made in France, has since enabled great advances.

The interior of Mars was so far "a big question mark", explained Banerdt, who has worked on this mission for more than ten years.

But thanks to InSight, "for the first time in history, we were able to map the interior of Mars."

Seismic waves, varying according to the materials they pass through, indeed offer a picture of the bowels of the planet.

For example, the scientists were able to confirm that the core of Mars is indeed liquid, and to determine the thickness of the Martian crust, less dense than previously envisaged and probably made up of three layers.

In addition, at the beginning of May, a shock much larger than all the previous ones was recorded.

Of magnitude 5, it would not have been huge on Earth, but turns out to be close to what scientists thought they observed at the most on Mars.

"This shock will really be a treasure trove of scientific information when we really look at it," said Bruce Banerdt.

On our planet, earthquakes are notably caused by plate tectonics, but not only, he explained.

In particular, the earth's crust can move under the effect of temperature anomalies caused by the mantle beneath it.

It is this type of vibration that scientists think they are dealing with on Mars.

The InSight mission also experienced a failure: an instrument had to be buried a few meters deep below the surface to take the temperature of the planet.

But due to the composition of the ground where the robot landed, this "mole" could not sink as expected.

Either way, given the success of the seismometer, NASA is considering using the technique elsewhere in the future, said Lori Glaze, the director of planetary sciences: "We would very much like to set up a complete network on the Moon , to really understand what's going on."

© 2022 AFP