PASADENA, Calif. – NASA’s Phoenix Mars Lander survived a fiery plunge through the
martian atmosphere May 25 to make a three-point landing on the red planet’s arctic plains, where it beamed back its first images to the delight of mission scientists.
“It looks as if the solar arrays have completely deployed, absolutely beautiful,” said Dan McCleese, chief scientist
here at NASA’s Jet Propulsion Laboratory (JPL). “It’s just beautiful, crystal clear images.”
The spacecraft touched down in the Vastitas Borealis plains within the m
artian arctic circle, where it is slated to spend at least three months searching for water-ice hidden away below the frozen surface. The descent and landing sequence went completely as planned.
“This team has performed perfectly … did you see that thing zoom down and then just touch?” said
Peter Smith, Phoenix’s principal investigator of the University of Arizona, where
the spacecraft will be controlled for the majority of its mission. “It’s not on a rock … it’s in a safe place.”
Mission scientists here at JPL received the signal that Phoenix had landed at around 7:53 p.m. EDT May 25 as expected.
The probe’s signals take about 15 minutes to traverse the 275 million kilometers between Mars and listening stations back on Earth.
The $420-million Phoenix mission, which launched in August 2007, is designed to dig down to the rock-hard layers of water-ice thought to lie under the martian soil in the northern arctic region. Phoenix’s arrival marked the first successful landing on Mars since NASA’s twin Spirit and Opportunity rovers bounced to a stop in 2004, and the first powered landing in more than 30 years for NASA.
The landing brings to an even 50-50 the percentage of successful and unsuccessful landing attempts on Mars – though the success rate for U.S. landings is much higher: 6 out of 7.
“For the first time in 32 years, and only the third time in history, a JPL team has carried out a soft landing on Mars,” NASA Administrator Michael Griffin said from JPL mission control. “I couldn’t be happier to be here to witness this incredible achievement.”
Phoenix is designed to test the martian soil and ice for signs that the water was once liquid to see if it could have created a habitable zone for microbial life at some point in the past. The instruments include a robotic arm that will scoop up dust and ice, as well as a wet chemistry lab and tiny ovens that will analyze the soil to see what compounds might be in it.
“The science team has been waiting patiently … and they are anxious to use their instruments,” Smith said.
Scientists were apprehensive about the craft’s seven-minute plunge through the martian atmosphere, but each stage went smoothly.
“In my dreams it couldn’t go as perfectly as it went tonight, we went right down the middle,” said Phoenix mission manager Barry Goldstein at JPL.
“We rehearsed all the problems and none of them occurred,” he added at a brief press conference just after landing.
“I was right to be optimistic,” Smith said, praising the mission team.
The radio blackout that scientists thought might occur during initial descent, a result of the fiery plasma created by friction as the craft descended that was predicted to interfere with the radio signal, never happened.
When asked during what part of the descent controllers felt their heart in their throat the most, Ed Sedivy, the Phoenix spacecraft manager from Lockheed Martin, said: “Well, for about the past four days.”
The craft landed on flat terrain, tilted by only one-quarter of a degree, meaning there were no rocks around to hinder the deployment of the solar arrays, which will provide the lander with energy for the duration of its three-month mission.
Scientists had their first linkup with Odyssey May 25, which relayed valuable information about the health of the spacecraft. These showed that the solar arrays had deployed successfully. Another image showed one of the lander’s footpads flat on the ground, and a third image showed the pancake-flat
martian arctic terrain, which has never been imaged from the surface before.