NASA is racing through space at more than 19,000 km / hreached Mars on Thursday and made an exhilarating seven-minute jump through the atmosphere on the surface of the red planet to look for evidence of past microbial life in the remains of an ancient lake.
“Touchdown Confirmed! Perseverance is safe on the surface of Mars and ready to search for the signs of past life!” Swati Mohan, a command, navigation, and control officer who oversees telemetry at the Jet Propulsion Laboratory, called when the rover touched down. Delighted, albeit socially distant, flight engineers broke out into cheers and applause, and fear gave relief to the joy of the moment.
The relief was understandable. Often described as “seven minutes of terror”, the descent of the rover was oneof computerized make-or-break events that had to work almost flawlessly in order to safely bring the 2,260-pound rover to an ancient lake in Jezero Crater, avoiding dangerous cliffs, large boulders and sand dunes.
And that’s exactly what the $ 2.4 billion rover did.
“I almost feel like I’m in a dream,” said Jennifer Trosper, assistant project manager. “Our job is to think about all the bad things that can happen and try to avoid them. When all good things happen, you feel like you are dreaming. And I’m glad I do , to dream!”
President Biden tweeted: “Congratulations to NASA and everyone whose hard work made the historic landing of Perseverance possible.”
The rover reached the top of the recognizable Martian atmosphere at 3:48 p.m. EST and quickly braked in a fire of atmospheric friction, its protective heat shield can withstand temperatures of up to 2,700 degrees – hot enough to melt stainless steel – and a braking force ten times the force of gravity on earth.
He slowed to just under 1,000 miles per hour, deployed a huge, 70.5-foot-wide parachute in the supersonic slipstream, and used an advanced guidance system to identify hazards and find a safe place to land on
Then, less than a minute after touchdown, Perseverance fell from its parachute at an altitude of about 2.1 miles while still descending at about 200 miles per hour. Seconds later, eight engines in a rocket-propelled backpack fired up, slowing the vehicle to less than 2 miles per hour, until it reached an expected altitude of only about 70 feet.
At this point the endurance was lowered towards the taped surface while the jetpack continued its descent. At 3:55 p.m. the six wheels of the rover settled on the surface, the lines were cut and the “Sky Crane” backpack flew off to collide at a safe distance.
“Hello world,” tweeted Perseverance a few minutes after landing and published the first picture of the rover from its landing site. “My first look at my home forever.”
Earth fell below the horizon from Jezero crater about a minute before touchdown, disrupting X-band radio signals from Perseverance direct to Earth. However, UHF signals confirming the landing were relayed to JPL from NASA’s Mars Reconnaissance Orbiter.
“The sky crane maneuver has begun. About 20 meters above the surface,” Mohan reported as the rover’s descent neared its end.
“We are still getting signals from MRO,” reported one engineer
“Touchdown confirmed!” Shouted Mohan a moment later.
A few moments later, the first image came in from one of the rover’s hazard cameras, showing a relatively flat surface with no large boulders or other obstacles. “YES! Whoo Hoo!” exclaimed an engineer as the photo flashed on the control room displays.
The rover’s automated descent appeared to be going smoothly as its flight computer used multiple cameras, radar, and other sensors to pinpoint exactly where it was in relation to its intended landing destination. The rover then adjusted its course as needed to avoid possible hazards at the end of the mission.
Persistence had to pull through the landing on its own, as radio signals moving at 186,000 miles per second took more than 11 minutes to cross the 127 million mile long gulf between Earth and Mars. The flight engineers at JPL could only sit and wait and watch as the data trickled in afterwards within 11 minutes.
And to her relief seven months laterl and an interplanetary cruise of 293 million miles, NASA’s fifth Mars rover, the first specifically designed to find signs of past life, was safely on the surface of the red planet.
Jezero crater was targeted because it once contained 45 km wide body of water the size of Lake Tahoe. The ancient lake was fed by a river that cut through the rim of the crater and deposited sediment in a fan-like delta that was clearly visible from orbit. The rover landed approximately 2 km southeast of the delta near the center of its predicted landing footprint of 4.8 x 4.1 miles.
“We think we’re facing southeast based on the shadows, about 140 degrees,” said Trosper. “The slope is shallow, it’s about 1.2 degrees. The power system looks good … everything looks good.”
A robotic geologist on Mars
Assuming no major problems arise, the engineers plan to spend about 90 days checking the rover’s complex instruments and systems.
In the first month, they also plan to deploy and test a small £ 4.5 million amount of $ 80 millionthat will attempt the first powered flight in the air of Mars, a “Wright Brothers Moment” on another world.
Another experiment will test the feasibility of extracting oxygen from the Martian atmosphere. This technology could one day help future astronauts produce their own air and rocket fuel.
However, the main objective of the mission is to look for signs of past biological activity.
Equipped with a robotic arm, a drill for core sampling and a number of sophisticated cameras, lasers with vaporizing rocks and other instruments, Perseverance will examine debris in the lake, venture across the delta and eventually make its way to the shores of the old lake and promisingly collect samples the way.
Selected rocks and soils are placed in a complex internal carousel mechanism, which autonomously photographs them, analyzes them and loads them into airtight tubes the size of lipstick. The rover then deposits or temporarily stores the sealed samples on the surface of Mars to await collection.
NASA and the European Space Agency plan to send another rover to Jezero later this decade to collect the samples, load them into a small rocket, and blast them into Mars orbit, where another spacecraft will fly them back will catch to earth.