Image credit: NASA/JPL-Caltech/University of Arizona
The flawless landing of Nasa's Phoenix probe was captured by the space agency's Mars Reconnaisance Orbiter in the early hours of yesterday morning. It is the first time one probe has caught another in the act of setting down on another planet.
After touchdown, the first flurry of images from Mars came from Phoenix itself. There were pictures of its dusty foot and the freshly unfurled solar arrays: the probe checking itself over after a lengthy and perilous journey. But then came another, perhaps more arresting image.
As Nasa's Mars Reconnnaisance Orbiter looped 472 miles overhead, it snapped Phoenix on the way down, its parachute deployed, just moments away from touchdown.
For more than 40 years, the odds of making a safe landing on Mars have been against the likes of Nasa. The sheer perfection of the Phoenix landing, and this icing-on-cake contribution from the MRO, suggest the learning curve might be flattening out. We might finally have worked out how to land on Mars reliably.
Mission controllers will begin analysing Phoenix's images from Mars immediately to identify the best spot for the probe to start digging. The hope is that the polygon scars on the surface are caused by thawing and freezing subsurface ice. If Phoenix can dig down and scoop up water ice, it will mark a major milestone in Nasa's strategy to "follow the water" in its search for life elsewhere.
"We can see cracks in the troughs that make us think the ice is still modifying the surface," said principal investigator Peter Smith at Arizona University
But let's be clear. No one is expecting Phoenix to find extant life. Not even microbes. At best, the mission may help scientists create a picture of the Martian polar environment, and reveal if it may once have been habitable for life. It's a small step, but it takes us closer to understanding one of the most profound questions humans have ever asked: are we the only ones out here?
