What has Curiosity taught us since we reached the Red Planet 10 years ago?

Six wheels, ultra-precision tools and hundreds of successful experiences. On Saturday, August 6, the Curiosity (“astronomical vehicle” in Moliere) mission celebrates 10 years of activity, since it was deployed to the surface of Mars by NASA in 2012. On its way, the 900kg machine took thousands of snapshots and probed soil Mars with one question in mind: Was the Red Planet ever habitable? “Proof”answers scientists, who have made many other discoveries, 78 million km from Earth.

Mars was habitable… about 3.5 billion years ago

This is the main lesson of the Mars Science Laboratory (MSL) mission, the project surrounding Curiosity: the (very) Red Planet long ago provided favorable conditions for the emergence of life. To reach this conclusion, the scientific teams experimented with the robot remotely, in order to scrape, scan and also drill Martian soil. “Little holes, little holes…”And the Enjoy the National Center for Space Studies (Cnes) Early 2020, referring to the song lilac punch, by Serge Ginsburg. Small holes, sure, but rich in discoveries. In fact, these wells made it possible to detect the presence of sulfur, oxygen, phosphorous or even carbon – “necessary for life”NASA says on his site*.

“It is the most important discovery, because it touches the great question of life”explains to France Info astrophysicist Sylvester Morris, who co-developed “ChemCam,” an instrument designed in part by two teams from the Institute for Research in Astrophysics and Planetary Science (IRAP) and Cnes in Toulouse (Haute-Garonne).

Embedded by Curiosity, this system makes it possible to analyze the chemical composition of a rock without moving the robot, thanks to a pulsed laser. “In ten years, we’ve fired 900,000 shots. (laser), proudly summarizing the world, All this from Toulouse and Los Alamos (US).” As Curiosity’s bot runs, MSL mission scientists are constantly communicating.

“You have to be careful when you want to order a laser shot, a shovel… It’s like driving a car with 60 people, all from a distance.”

Sylvester Morris, astrophysicist

in franceinfo

Another important discovery: a large number of organic molecules were discovered by Curiosity Thanks to SAM Mini Lab, also operates from Toulouse. But beware, these particles do not prove the existence or still life of organisms on Mars. They just show it “Basic components were present to support a simple form of life 3 billion years ago”, Valerie Mousset, MSL Project Manager at Cnes points out, who adds that “All the chemical compounds in our DNA are also on the surface of Mars.”. This investigation into the effects of Martian life is not the work of Curiosity, but the work of To her little sister, the persevering, the rover who has been traveling on Mars since February 2021.

Water flowed in liquid form for a long time over the Red Planet

Water was an essential component of life as we know it on Earth, and it was at the center of all concerns during Curiosity’s launch. Since then, several evidence has indicated that streams, or even freshwater rivers, were once part of the Martian landscape. pebbles, spotted by the rover, whose round shape can be the result of a long journey along the bottom of a stream NASA advances*.

But also deposits of hardened clay, discovered at the bottom of what look like dry riverbeds. This justifies the choice of landing site (from Curiosity), explains to franceinfo Olivier Gasnault, current director of ChemCam at Cnes. The rover was sent to what was a fairly enclosed lake (…) in order to confirm the hypotheses that had been formulated for several decades already.“

Curiosity also allowed us to learn more about the properties of Martian water, which was Not too acidic nor too basic. Valerie Mousset explains, with a temperature qualifying as “neutral” she also. Presence of mud and a relatively low level of salt So tell NASA*From this water “It was fresh and probably drinkable”. Before the shape change, there are more or less two billion years.

An unprecedented view of the surface of Mars

All of these discoveries are made possible by careful observation of the Martian environment, including Grace or grace Up to 17 cameras on board the rover provide views in all directions. Since arriving on Mars, Curiosity has traveled just over 28 km, with an average of 7.6 meters traveled each day. Yellowknife Bay, Pahrump Hills, Buttes de Murray or the foothills of Mount Sharp: in these mysterious places the rover has traveled. A scientific career immortalized by more than 500,000 photographs – including Some selfies In front of unusual rocks.

On the rover mast, a part often described as the head of the device, the MastCam for example is capable of capturing color photos and videos, as well as 3D stereo images. Thanks to special filters, this sensor can highlight the composition of certain rocks. Curiosity also has a Mars Hand Lens Imager (MAHLI), which is the equivalent of a magnifying glass attached to the end of a robotic arm, capable of observing microelements such as human hair. Landscape photos in detail Meteor encountered on the way*, Curiosity continues to provide an amazing panorama of the red planet.