On Thursday, February 18, when NASA received the message that persistence had entered the atmosphere of Mars, the rover’s destiny was already closed. of courseIt takes exactly 11 minutes and 22 seconds for the radio signal to travel at 205 million kilometers per hour, which separates the Earth from Mars. So NASA engineers fully automated the advent of the mobile robot. A follow-up visit to Franceinfo.fr, NASA website Or, in French Cnes site.
Seven minutes before docking
Since its launch on July 30, 2020, the steady state has traveled 471 million kilometers, at a speed of 85,000 kilometers per hour. By the time Mars enters its atmosphere, it has only fifty kilometers to reach its exploration site.
But this seven-minute flight was the most dangerous of his long journey. At this moment, the speed of the capsule carrying the steady state is still 20,000 kilometers per hour. The lower the capsule drops into the Martian atmosphere, the higher its cabin temperature than 1,300. This collision with the atmosphere of the Red Planet, which is protected by its heat shield, greatly slows the capsule.
Four minutes before docking
The speed of the capsule is reduced to 1,200 kilometers per hour, approximately the speed of sound. This is when the capsule activates its supersonic parachute from the rear. This parachute was designed based on what was allowed Curiosity, The forerunner of the perseverance to successfully land on the Red Planet in 2012.
The canvas of this parachute is 21.5 meters wide, equivalent to a large house, and deploys within half a second. Return to the steady-state capsule: the on-board device receives information about speed and altitude. So he can activate the supersonic parachute at the right time. The speed of the braking capsule, which is linked to the parachute, is reduced to 300 km / h.
Two minutes before docking
The most dangerous stage is yet to come. At an altitude of 4 km above the surface of Mars, the rover and the sky crane (named after its space crane) are removed from the capsule, which has been in orbit for seven months. Soon, eight retrorockets of the Sky Crane began to gradually reduce its speed to 30 kilometers per hour, stabilizing the machine and placing it 20 meters above the landing site, located in the Jessero crater.
Within 30 seconds the perseverance will touch the soil of Mars. Then, thanks to three nylon cables, the Sky Crane of Perseverance is investing a whopping $ 2.5 billion on Mars. Disconnect the cables from the rover as soon as possible. The risk is that his flying crane will be towed. It’s going to crash tens of thousands of meters away.
After 11 minutes, NASA scientists will be able to determine if the rosary can begin its mission: for evidence of ancient life on the Red Planet.