The Big Day for Perseverance has arrived! After an interplanetary journey started in July, the NASA “rover” has landed on the rusty Martian surface this Thursday.
Before landing its six wheels on the ground of the Red Planet, the space agency’s space vehicle had to survive “seven minutes of terror,” as this dangerous maneuver is nicknamed. A precision choreography in which all the elements must work perfectly.
The rover has deployed its parachute and has completed all operations normally. Even his operations camera has sent the first photo.
Many others will follow, in much greater detail.
The chosen site, Jezero Crater, was the most dangerous landing site ever attempted. In seven minutes, the rover had to go from a speed of 20,000 km / h to zero.
Behind the screens of the control center, the stress will be great for the researchers participating in the “Mars 2020” mission, which has a budget of almost 2,500 million dollars (more than 2,000 million euros).
The “lucky peanuts” were not lacking in the control center. A little superstition in the middle of science.
Scientists will receive the images later, but they listen to the spacecraft’s “heartbeat,” which tells them in real time that everything is fine (or not).
Watch the landing broadcast again on the player above. Courtesy NASA TV
These are the different stages of these “7 minutes of terror” before landing:
130 km from the ground of Mars: entry into the atmosphere
Ten minutes before entering the Martian atmosphere, the ship will detach from its cruise module, which supplied it with fuel during the trip, among other things.
Thus, only a rear shield will remain, a heat shield in the front and, trapped between them, the descent module that is connected to the rover vehicle itself.
At an altitude of about 130 km, it enters the atmosphere at a speed of 20,000 km / h, causing friction that raises the temperature to 1,300 ° C. The heat shield protects the rover from this infernal heat.
11 km from the ground: parachute opening
But the atmosphere is not enough to slow the spacecraft, which is still going 1,500 kilometers per hour.
At a height of about 11 km, at an opportune moment calculated based on the remaining distance to the landing site, a huge supersonic parachute 21 meters in diameter is deployed, located on the rear shield.
This slows the ship at about 300 km / h.
9 km above ground: detachment of the heat shield
20 seconds after opening the parachute, the heat shield is released. Perseverance is exposed to the Martian atmosphere for the first time.
An entirely new technology comes into play, called Terrain Relative Navigation (TRN): live images recorded by on-board cameras are compared with maps stored in your system, where dangerous areas to avoid are predefined. From these data, the ship decides the final landing site.
2 km from the ground: retro-propulsion phase
At a height of about 2 km, the rear shield – and its parachute – are released.
The rover is now attached solely to the descent stage, equipped with eight downward-pointing engines that turn on to finish braking it. After maneuvering away from the parachute, the rover ends up descending vertically, just above the landing site.
20 m above ground: rover separation
At about 20 meters above the ground, it reached a speed of 2.7 km / h, slower than that of a man walking. The rover then descends on cables using a pulley system for about fifteen seconds (a stage called “skycrane”).
The vehicle unfolds its wheels at this time. When the wheels touch the ground, the lines are cut and the descent stage makes one last effort to crash as far as possible.
Due to the delay in transmission between Earth and Mars, when NASA confirms the landing, it will actually have taken place several minutes earlier.
Perseverance equipped with European instruments
Perched atop NASA’s rover, the French-designed SuperCam instrument will study Martian rocks with sound and light, with its laser beam and a microphone, looking for traces of past life on the red planet.
The size of a shoebox and weighing in at about five kilos, SuperCam will display its “superpowers” from the top of a pole. With additional American analysis and control tools placed inside the body of the rover.
Three other European instruments will participate: the Spanish MEDA, a meteorological station that will measure wind, temperature, humidity, atmospheric pressure, and Martian dust to prepare the ground for future expeditions. The Norwegian RIMFAX is a radar that will study the Martian subsoil and the Italian RETROREFLECTOR that will be a “beacon” for future missions.
The objective of this mission is to analyze the soil of the Red Planet in search of possible traces of life in the past and to advance in the study of a possible human exploration of Mars.
Of course, Perseverance already has her own social media accounts where she will share her adventures and discoveries.