Cheers and applause echoed through the NASA Jet Propulsion Laboratory late Sunday after the most high-tech interplanetary rover ever built signaled it had survived a harrowing plunge through the thin Mars atmosphere.
"Touchdown confirmed," said engineer Allen Chen. "We're safe on Mars."
Minutes after the landing signal reached Earth at 10:32 p.m. PDT (0532 GMT), Curiosity beamed back the first black-and-white pictures from inside the crater showing its wheel and its shadow, cast by the afternoon sun.
Hundreds watch the images from Mars on the big screen beamed by Nasa's Curiosity rover which landed at the US Space and Rocket Center in Huntsville, Ala. AP/The Huntsville Times, Eric Schultz
"We landed in a nice flat spot. Beautiful, really beautiful," said engineer Adam Steltzner, who led the team that devised the tricky landing routine.
It was NASA's seventh landing on Earth's neighbor; many other attempts by the U.S. and other countries to zip past, circle or set down on Mars have gone awry.
In this 2011 file artist's rendering, a "sky crane" lowers the Mars Science Laboratory Curiosity rover onto the surface of Mars. AP/Nasa/JPL-Caltech
The arrival was an engineering tour de force, debuting never-before-tried acrobatics packed into "seven minutes of terror" as Curiosity sliced through the Martian atmosphere at 13,000 mph (21,000 kph).
In a Hollywood-style finish, cables delicately lowered the rover to the ground at a snail-paced 2 mph (3 kph). A video camera was set to capture the most dramatic moments — the first glimpse of a touchdown on another world.
For details on Curiosity rover mission, click here.
Celebrations by the mission team were so joyous over the next hour that JPL Director Charles Elachi had to plead for calm in order to hold a press conference. He compared the team to athletic teams that go to the Olympics.
"This team came back with the gold," he said.
Mars Science Laboratory (MSL) Curiosity Rover mission managers, flight controllers, scientists and administrators speak at a press conference after the Mars Rover Curiosity successfully landed on the surface of the Red Planet. AFP PHOTO / ROBYN BECK
The extraterrestrial feat injected a much-needed boost to NASA, which is debating whether it can afford another Mars landing this decade. At a budget-busting $2.5 billion (€2 billion), Curiosity is the priciest gamble yet, which scientists hope will pay off with a bonanza of discoveries.
Mars Science Laboratory Curiosity Richard Cook, MSL deputy project manager, left, and Adam Steltzner, MSL entry, descent and landing (EDL) lead, right, point to the first image taken by NASA's Curiosity rover. (AP Photo/Damian Dovarganes)
President Barack Obama called the landing "an unprecedented feat of technology that will stand as a point of national pride far into the future."
Over the next two years, Curiosity will drive over to a mountain rising from the crater floor, poke into rocks and scoop up rust-tinted soil to see if the region ever had the right environment for microscopic organisms to thrive. It's the latest chapter in the long-running quest to find out whether primitive life arose early in the planet's history.
In this image from NASA TV, shot off a video screen, one of the first images from the Curiosity rover is pictured of its wheel after it successfully landed on Mars. Reuters/Courtesy NASA TV
The voyage to Mars took more than eight months and spanned 352 million miles (566 million kilometers). The trickiest part of the journey? The landing. Because Curiosity weighs nearly a ton, engineers created a more controlled way to set the rover down. The last Mars rovers, twins Spirit and Opportunity, were cocooned in air bags and bounced to a stop in 2004.
Curiosity relied on a series of braking tricks, similar to those used by the space shuttle, a heat shield and a supersonic parachute to slow down as it punched through the atmosphere.
And in a new twist, engineers came up with a way to lower the rover by cable from a hovering rocket-powered backpack. At touchdown, the cords cut and the rocket stage crashed a distance away.
The nuclear-powered Curiosity, the size of a small car, is packed with scientific tools, cameras and a weather station. It sports a robotic arm with a power drill, a laser that can zap distant rocks, a chemistry lab to sniff for the chemical building blocks of life and a detector to measure dangerous radiation on the surface.
It also tracked radiation levels during the journey to help NASA better understand the risks astronauts could face on a future manned trip.
Over the next several days, Curiosity was expected to send back the first color pictures. After several weeks of health checkups, the six-wheel rover could take its first short drive and flex its robotic arm.
The landing site near Mars' equator was picked because there are signs of past water everywhere, meeting one of the requirements for life as we know it. Inside Gale Crater is a 3-mile-high (5-kilometer-high) mountain, and images from space show the base appears rich in minerals that formed in the presence of water.
Previous trips to Mars have uncovered ice near the Martian north pole and evidence that water once flowed when the planet was wetter and toastier unlike today's harsh, frigid desert environment.
Curiosity's goal: to scour for basic ingredients essential for life including carbon, nitrogen, phosphorous, sulfur and oxygen. It's not equipped to search for living or fossil microorganisms. To get a definitive answer, a future mission needs to fly Martian rocks and soil back to Earth to be examined by powerful laboratories.
The mission comes as NASA retools its Mars exploration strategy. Faced with tough economic times, the space agency pulled out of partnership with the European Space Agency to land a rock-collecting rover in 2018. The Europeans have since teamed with the Russians as NASA decides on a new roadmap.
Despite Mars' reputation as a spacecraft graveyard, humans continue their love affair with the planet, lobbing spacecraft in search of clues about its early history. Out of more than three dozen attempts — flybys, orbiters and landings — by the U.S., Soviet Union, Europe and Japan since the 1960s, more than half have ended disastrously.
One NASA rover that defied expectations is Opportunity, which is still busy wheeling around the rim of a crater in the Martian southern hemisphere eight years later.
Why mars again?
The big unknown remains. Scientists want to know if any form of life ever existed there, and that means microscopic organisms. Curiosity is the most ambitious effort ever to burrow into that question, though it is not equipped to look for actual microbes. During its two-year exploration, it will try to answer whether the giant crater had the right conditions to support that type of life.
What will curiosity do?
Curiosity carries a toolbox of 10 instruments, including a rock-zapping laser and a mobile organic chemistry lab. It also has a long robotic arm that can jackhammer into rocks and soil. It will hunt for the basic ingredients of life, including carbon-based compounds, nitrogen, phosphorus, sulfur and oxygen, as well as minerals that might provide clues about possible energy sources.
How much did this cost?
$2.5 billion. Development took longer than planned, delaying the mission for two years and costing $1 billion more than the original budget. But that extra time is credited in part with the safe landing of the one-ton rover which required new technologies and highly complicated maneuvers.
When will we send astronauts to mars?
President Barack Obama has set a goal for astronauts to orbit Mars by the mid-2030s followed by a landing. Before that can happen, the plan is to send astronauts to an asteroid first.
For details on Mars missions, click here.