NASA’s Perseverance rover completed its intricate dance and landed safely on the surface of Mars at 3:49 p.m. ET on Thursday.
“Touchdown confirmed!” Swati Mohan, the operations lead for the mission, announced as applause erupted in the control room at the Jet Propulsion Laboratory in California. “Perseverance is ready to begin sifting the sands for past life!”
The safe landing was far from a foregone conclusion. “There’s a lot that can go wrong,” Rob Manning, chief engineer at the Jet Propulsion Laboratory and a veteran of several Mars landings, explained prior to the successful touchdown.
As Perseverance plummeted at a top speed of three miles per second through Mars’ thin atmosphere, Mission-controllers nervously munched peanuts—a NASA tradition since the 1960s.
But nothing went wrong. The $2.7-billion Perseverance not only landed intact on the floor of the Jezero Crater—a vast, dried-up lake—it actually fired up its cameras and radio transmitters within seconds, surprising the mission-controllers.
The first photos, beamed across the vast expanse of space, let the world see what the rover saw—a vast, arid and alien landscape stretching seemingly endlessly toward a cloudless horizon.
“This is so exciting,” Manning breathed.
— NASA's Perseverance Mars Rover (@NASAPersevere) February 18, 2021
Seven months after blasting off from Cape Canaveral, Perseverance arrived on the Red Planet, 290 million miles from Earth.
The six-wheeled rover’s planned, two-year mission is just the first phase in a decade-long scientific campaign with two main goals: to look for evidence of life and prepare the Red Planet for future waves of human explorers.
“Every flagship mission has a lot riding on it,” Roger Launius, a space historian in Alabama, told The Daily Beast before the successful landing. “First there is the cost, and a loss of the spacecraft means years of waiting—and a new round of funding—to recover. The loss to the scientists is also great. They spend years on these missions, having to develop and fly the spacecraft to Mars. They get no scientific data until they have invested a lot of time in the effort. If it fails, they have nothing to show for their effort.”
Perseverance, NASA’s fifth Mars rover since 1997 and a direct successor to the agency’s famous Curiosity rover, is actually the third Earth robot to approach Mars this month. The United Arab Emirates’ Hope probe, the country’s first, slipped into the Red Planet’s orbit on Feb. 9.
The Chinese space agency’s own first Mars probe, Tianwen-1, arrived a day later. Hope is an orbital instrument, meaning it’s not equipped to explore the planet’s surface. But Tianwen-1, like NASA’s Mars 2020, includes a rover. The Chinese space agency is biding its time, however, carefully scanning the Red Planet’s surface before attempting to land the rover in late May using a combination of a parachute, backfiring brake rockets and airbags.
NASA took the opposite approach with Perseverance. The plan was for the lander, clutching the rover to its belly, to barrel straight toward the planet’s Jezero Crater—a vast extinct lake that scientists believe dried up billions of years ago—at 13,000 miles per hour. “Seven minutes of terror,” NASA calls it.
It was all controlled by the probe’s own on-board computers. During the final entry, descent and landing, mission control at the Jet Propulsion Laboratory in Pasadena, California was powerless to intervene.
First, a heat shield peeled off after reaching a temperature of 1,600 degrees Fahrenheit. By then the lander was traveling a thousand miles per hour. Next, a special, super-strong parachute will deployed, snapping open with a force of 65,000 pounds.
The parachute slowed the lander to 200 miles per hour, still too fast to land. In the final seconds of its fiery descent, the lander fired maneuvering rockets—first blasting sideways to get the lander clear of the parachute, then blasting downward to slow the descent rate to zero.
There was a final, breathless step that NASA engineers designed in order to keep Perseverance clear of the damaging clouds of dust that rockets tend to kick up. Hovering 60 feet over the surface, the lander lowered the rover on cables—a method NASA calls “skycrane.”
It was a complex ballet involving a hypersonic spacecraft, a molten-hot heat shield, parachute-induced whiplash, rockets firing in two directions and a precise crane maneuver that would have been nerve-wracking even if it weren’t happening under computer control hundreds of millions of miles away.
The stakes were enormous. “All of the previous rover missions have been building up to Perseverance, from Spirit and Opportunity who showed that Mars supported liquid water, to Curiosity who showed that those ancient water environments were habitable for life,” Briony Horgan, a planetary scientist at Purdue University in Indiana, told The Daily Beast.
“And now Perseverance will search for signs of that ancient life,” said Horgan, who helped NASA select the Jezero Crater for Perseverance’s landing.
NASA is counting on Perseverance to check off a long list of surveys, collections and experiments. It’s got cameras. A ground-penetrating radar for mapping whatever lies beneath Mars’s dry surface. An oxygen-generator that, if it works, could help future human explorers manufacture breathable air on the Red Planet.
Perseverance is also hauling a tiny prototype drone helicopter called Ingenuity. If Ingenuity performs as planned in the thin Martian atmosphere, future missions could deploy swarms of tiny ‘copters for rapid aerial surveys of the planet.
But the 43 soda-bottle size titanium sample tubes might be the rover’s most important payload. Perseverance will fill the tubes with mineral samples by plunging them into the ground and sealing them. It will then haul the full tubes to a cache somewhere in the Jezero Crater and carefully log its location before its systems start wearing out. NASA engineers expect that use-by date to come within a couple years.
The plan is for NASA to send another rover—plus a small rocket called an “ascent vehicle”—to Mars sometime in the next decade. The new rover would fetch Perseverance’s sample tubes and place them inside the ascent vehicle, which would blast into orbit and rendezvous with another spacecraft for the return voyage to Earth, perhaps as early as 2031.
This relay-race approach to space exploration is new. “We always have a goal—look for life, look for water, look for ice,” Matthew Siegler, a Texas-based physicist on the Perseverance team, told The Daily Beast. “But this is different, something akin to a rescue mission to bring back the gold—the start of a cosmic game of capture-the-flag.”
The contents of the tubes could fuel decades of intensive study. It’s in these samples of soil and rock that many scientists hope to find clear evidence of extinct, or surviving, microbial life. The first hard proof that we and our fellow Earth creatures aren’t the only living things in the universe.
It’s not for no reason NASA decided to send Perseverance to the Jezero Crater. Life craves water. The crater probably once held an awful lot of it. Jezero’s rocks could tell the tale. “If we can someday date those rocks, we can figure out when Mars was wet and possibly for how long,” Marisa Palucis, a geologist at Dartmouth College in New Hampshire, told The Daily Beast.
Perseverance’s precious samples could return to Earth around the same time NASA’s long-planned manned mission to Mars finally blasts off. Those explorers could owe their eventual success to work the rover is about to do, mapping Mars’ surface, testing survey drones and tinkering with an oxygen-generator.
They might also owe their purpose to Perseverance. If the rover does indeed collect evidence of life, further understanding that life surely will be one of the main aims of any follow-on manned mission to the Red Planet.
The first step for Perseverance was the most dangerous. It had to survive seven minutes of terror and land safely on the Red Planet.