NASA’s latest robotic explorer will arrive on Mars Thursday afternoon, and it is the third spacecraft to reach the planet this month after visitors from The United Arab Emirates And the China. The Perseverance Chariot heads to Jezero Crater, a place planetary scientists believe could be an ideal place to find signs of life preserved several billion years ago, should life emerge on Mars.
But first, the NASA mission must land in one piece.
When is the landing and how do I follow it?
Landing is expected at around 3:55 PM ET. NASA TV The coverage will begin broadcasting from the Mission Control Room at JPL in California at 2:15 pm
While landing, the spacecraft will send updates on how it is operating. Since its main antenna would not be pointing at Earth, its direct connections would be just a series of simple tones.
“We can use these tones to tell us about different things, like the heat shield falling off or something like that,” said Allen Chen, the lead engineer for the landing portion of the mission, during a press conference on Wednesday.
The perseverance will likely send some images from the surface via NASA’s Mars Reconnaissance Orbiter, but it could take hours to arrive. “If we get that, it’s golden,” said Jennifer Trosbear, deputy project manager for the mission.
Why is landing on Mars so difficult?
In short, the persistence will have to slow from more than 12,000 miles per hour to a complete stop during what NASA calls “seven minutes of terror”, for the period of time from the rover entering the atmosphere to its descent. There is no chance to overtake. The path of perseverance will intersect the surface of Mars. The only question is whether the rover will end up in one piece, ready to begin its mission, or will it shatter into many pieces.
The thin atmosphere of Mars adds several levels of difficulty. The spacecraft needs a heat shield, because friction from the air particles heats its underside to thousands of degrees. But not enough friction to slow it down for a nice parachute landing only.
What will happen during the attempt to land?
The spacecraft will have to handle the landing on its own. It takes 11 minutes for the radio signal to travel from Mars to Earth. This means that if something goes wrong, it will be already too late by the time the folks at NASA’s Mission Operations Center get the word out.
“It all has to happen independently,” said Matt Wallace, deputy project manager. “Perseverance really has to make its way to the surface on its own. It’s like the controlled disassembly of a spacecraft.”
About 80 seconds after entering the atmosphere, the spacecraft experiences peak temperatures, with the heat shield at the bottom of the capsule reaching 2,370 degrees Fahrenheit. Inside the capsule, much less heat – around room temperature. As the air becomes denser, the spacecraft continues to slow down.
Small thrusters on top of the capsule adjust its angle and direction of descent and keep it in its path toward its landing site.
At an altitude of about seven miles, four minutes after entering the atmosphere, the capsule is moving at speeds of less than 1,000 miles per hour. Then it deploys a huge parachute with a diameter of more than 70 feet.
The spacecraft is now dropping the heat shield, allowing cameras and other tools to monitor the terrain below to determine its location.
Even with the huge parachute, the spacecraft is still crashing at 200 mph.
The next critical step is called the Sky Crane maneuver. The top of the capsule, called the back cover, is left out and carried away by the parachute. Two pieces of the spacecraft remained. The top is the landing stage – essentially a missile-powered jet that carries the rover below it. Landing stage motors steer first to avoid hitting the back cover and canopy. Then the engines slow the descent to less than two miles an hour.
66 feet above the roof, the rover is launched on cables. The descending phase continues until the rover’s wheels reach the ground. The cables are then cut, and the landing stage flies away to crash at a safe distance from the rover.
What are the odds of this succeeding?
I already worked once. The Curiosity spacecraft, currently on the surface of Mars, successfully used the same landing system in 2012. But spacecraft are complex systems, and one success does not guarantee a second success.
Tenacity has stronger parachutes and a more accurate navigation system. NASA engineers say they tried to take Each step improves the chances of success of everythingBut they don’t know if they’ve detected every emergency.
“We never found a good way to calculate the likelihood of success,” said Mr. Wallace, Deputy Project Manager.
Over the decades, NASA has succeeded in eight of the nine attempts to land on Mars. The only failure was the Mars Polar Lander in 1999.
“I’m going to be very nervous,” admitted NASA’s Acting Administrator, Steve Jorsesk, in an interview.
What will the probe do on Mars?
Over the past 20 years, NASA has gradually asked more complex questions about Mars. First, the mantra was “follow the water”, as there may have been life once upon a time. With giant canyons, winding river channels and dry lake markings, it was clear that in the past water was flowing on Mars even though the planet is cold and dry today.
The destination of perseverance is Jezero Crater. The rover will explore the delta of the river that once flowed into a crater lake. The sediment mounds are a promising place where the fossil chemical signatures of ancient Martian microbes can still be preserved.
The rover is very much the same design as the Curiosity rover, which is now studying the Gale Crater. But it does carry a variety of tools, including advanced cameras and lasers that can analyze the chemical composition of rocks and ground-penetrating radar. Tests these tools on the ground Show potential to find preserved signs of past lives.
What about a “marquee”?
NASA’s new rover carries a four-pound helicopter called Ingenuity He will try something that has never been done before: the first controlled flight into another world in our solar system.
Flying on Mars is no easy feat. There isn’t a lot of air in there to squeeze to generate lift. On Mars, the atmosphere is only 1/100 of the density of Earth’s atmosphere. Less gravity – a third of what you feel here – helps with flying. But taking off from the surface of Mars is equivalent to flying in the air as delicately as can be found at an altitude of 100,000 feet on Earth. No ground helicopters have flown this altitude, which is more than twice the altitude at which jets usually fly.
NASA engineers used a series of materials and advances in computer technology to overcome a number of these challenges. About two months after landing, the helicopter’s Perseverance would descend from its belly, and Creativity would attempt a series of about five test flights of increasing duration.
If successful, the tests could pave the way for larger marquises in the future. Having the option to use robotic prisms could greatly expand the space agency’s ability to study the Martian landscape in more detail, just as the transition from fixed landers to rovers did in previous decades.