The Phoenix has landed.
After a nine-month, 422 million-mile voyage, followed by a delicate series of maneuvers that slowed the Phoenix Mars Lander from about 13,000 mph to just 5 mph at touchdown seven minutes later, the National Aeronautics and Space Administration tonight has placed a spacecraft on the Martian surface.
"A signal has been detected from Phoenix indicating that the lander is on the surface of Mars," NASA reported on its Web site just after the 7:53 p.m. EDT landing.
For NASA, the successful landing was a long time coming. More than eight years ago, in December 1999, NASA's Mars Polar Lander project came to a disastrous end when the craft's descent engines shut down too early as it prepared to land on the Martian surface. That lander went out of control from a high altitude, crashed and was destroyed.
That mission was followed by the successes of the two 2004 Mars rover missions, which have been traversing the planet in a series of experiments and exploratory missions. The rovers, however, were delivered to the Mars surface in large, cushy "air bags" that bounced onto the surface. Later, the air bags deflated, and the rovers drove out of them and began their work.
Lander descents are much trickier, because they use large parachutes and thruster engines to bring the craft into a controlled approach to the surface.
The last time NASA had successfully landed a spacecraft this way on Mars was in 1976, when the Viking I and Viking II landers touched down safely for a series of science and photography missions.
At NASA's Jet Propulsion Laboratory in Pasdena, Calif., where the mission is being monitored, the safe touchdown of the Phoenix brought cheers and smiles, said Randii Wessen, a NASA project system engineer. "We were all cheering and hugging," he said. "These things are like your children. You want them to succeed. We're all excited."
As the lander approached the planet's surface, "it gently touched the ground," Wessen said. "At about 5 mph, it just parked [itself]. It's got about a one-degree tilt. It's just parked very neatly and flat. It's just great."
Once the dust raised by the descent thrusters settled after a few minutes, Phoenix deployed its solar panel array so it could begin generating electricity for its experiments and other onboard systems, Wessen said.
With the panels deployed, the lander began sending data back to Earth via three orbiting spacecraft that were relaying the information to project scientists. The first live photographs from Phoenix began arriving about 10 p.m. EDT.
The subject of those first photos included the craft's solar panels, so NASA officials could be sure that the panels were properly deployed, according to Wessen.
The Phoenix now begins a three-month-long science mission made up of a series of projects that involve digging lightly into the Martian surface to analyze the soil for the history of water, ice and the potential for life on that planet.
"We think it's way cool," Wessen said of the successful landing.