NASA’s Phoenix probe has completed its 422 million mile journey and safely landed on Mars where it will begin its search for water and life. UK scientists involved in the mission, and present at the University of Arizona’s Science Operations Centre for the landing, waited tensely as the probe made its tricky descent to the surface of the red planet’s northern plains. At 00:53 BST, the tense wait was over when Phoenix sent home its first signals from the Martian surface.
One objective of Phoenix is to monitor the polar weather and the interaction of the atmosphere with the surface. The polar atmosphere during summer is a quite different environment compared to that visited by previous landers. During the northern summer it’s believed that water vapour is driven off ice at Mars’ north polar cap and enters the atmosphere.
David Catling from University of Bristol and science team co-investigator on the mission to study this relationship said, ‘It’s fantastic that Phoenix is safely down in the northern lowlands of Mars. Our priority now is to find out if there is ice below the dirt, and whether it got there recently or is a frozen remnant from an ancient time when liquid water may have rippled across this part of Mars.’
Professor Keith Mason, Chief Executive of the Science and Technology Facilities Council, who support the UK involvement in the mission said, ‘Phoenix’s safe landing marks the start of some very exciting research on Mars. This is the first chance we’ve had to actually collect and analyse water on the red planet. If we find water ice below the Martian surface we may also be able to find evidence of past life on the planet.’
One minute after landing, Phoenix stopped transmitting and focused its limited battery power on opening its solar arrays, and other critical activities. Two hours after touchdown, it sent its first pictures which confirmed that the solar arrays needed for the missions energy supply had unfolded properly, and masts for the stereo camera and weather station had swung into position.
Over the next nine days the instruments will continue to take initial measurements of the Martian atmosphere and soil before the robotic arm is used to dig through the frozen Martian soil to the water ice layer beneath. The arm will lift samples of both soil and ice to the craft’s onboard laboratory instruments for detailed scientific analysis. The cameras and weather station will supply other information about the site's environment.
Dr Tom Pike, who heads up the UK Phoenix team for Imperial College London, said, ‘We’re all so relieved that Phoenix has managed to land safely. The descent and landing phase of the mission is one of the most tricky and hazardous. It’s great to have made it down in one piece and now we can get to work uncovering more of the red planet’s secrets.’
Supported by grant funding from STFC, the Phoenix team at Imperial College London have provided micro-machined silicon substrates which provide a surface on which to hold the dust and soil samples for analysis in the microscope station attached to the Lander. The grains of Martian dust and soil, delivered by the mechanical excavation arm, will be imaged by an optical microscope and an atomic force microscope. Together they will provide the highest resolution imaging ever taken on another planet.