Washington (AFP)
More than a century after the first powered flight on Earth, NASA intends to prove that it is possible to fly a machine on another planet.
Transported aboard the Mars 2020 mission, which arrives at its destination on Thursday, the small Ingenuity helicopter will have to accomplish a feat: rise in air with a density equivalent to only 1% that of the Earth's atmosphere.
- Ultralight helicopter
Ingenuity actually looks more like a big drone.
The main challenge for engineers: to make it as light as possible, so that it can lift itself in extremely light air.
It ultimately weighs only 1.8 kg.
It is composed of four feet, a body and two superimposed propellers.
It measures 1.2 meters from one end of a blade to the other.
The propellers will spin at a speed of 2,400 rpm (revolutions per minute), which is about five times faster than a standard helicopter.
Ingenuity is equipped with solar panels to recharge its batteries, much of the energy being used for warming up (it is -90 ° C at night on Mars).
It can also take photos and videos.
The helicopter was placed under the belly of the Perseverance rover, the main mission vehicle.
Once on Mars, it will be dropped on the ground, and the rover will roll over it to get away from it.
- 90 second flights
Up to five flights of gradual difficulty are planned, over a window of one month, at the very start of the mission.
It can rise up to 5m in height, and move up to 300m, but it will go much less for the first test.
Each flight can last up to a minute and a half, "which is no small feat compared to the 12 seconds" of the first powered flight on Earth, argues NASA.
Because of the transmission delay of about twenty minutes between Earth and Mars, no joystick to control it.
It will fly independently: commands will be sent but it will then have to fend for itself thanks to a series of sensors helping it to navigate.
The results of the flights will be received long after their outcome.
- To do what?
This experiment is what NASA calls a demonstration mission: it has no scientific objective, except to prove that it is possible to fly on Mars, and to collect data on the behavior of a ship on another planet.
In the future, such machines could "usher in a whole new era of Mars exploration," enthuses Bob Balaram, chief engineer of the project.
By going for example where rovers cannot go (above canyons ...).
We can also imagine that they would go to look for, then bring back to a base, samples deposited by previous missions.
For example, the samples that Perseverance must start collecting, in the next phase of the March 2020 mission.
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