Back in May, I wrote that NASA’s latest Mars lander, Phoenix, was wearing “a thick overcoat of frost” in a feature for BBC Sky at Night magazine.
I never expected actually to see that wintry shroud. But astonishing new pictures by a powerful space camera have picked out the scene, high in the martian arctic.
The HiRISE camera aboard NASA’s Mars Reconnaissance Orbiter picked out the now silent Phoenix, blanketed with frozen carbon dioxide, as winter began to give way to spring.
The probe had pictured the craft before during martian summer at the landing site on the plains of Vastitas Planum 68%deg; north in the planet’s northern hemisphere.
At that time, in June 2008, the region was frost-free and the robot lander was busy digging into the soil to find water ice and observing martian weather following its successful landing on 26 May. The probe stood out clearly – along with the discarded parachute and heat shield in the full wide-angle image.
Lighting was poor for the latest pictures, taken in July and August this year, with the sun low over the horizon and atmospheric haze. But the probe is once again visible though much less distinctly thanks to its icy coating. HiRISE scientists at the University of Arizona say the apparent brightness of areas in the newer photos do not necessarily represent the amount of frost.
Even darker areas on the winter pictures are in reality brighter than the soil around the lander in the summer image. The reason they look darker is due to the processing of the raw data in producing the pictures.
Phoenix fell silent just over a year ago, on 2 November 2008. The Phoenix team were planning to try to see if it could be raised from the dead around now.
Principal Investigator Professor Peter Smith told Skymania News: He said: “Frosts of around -130C can create a layer on the surface as much as 30cm deep and in some places even a meter.
“That’s solid, dry ice – you’d need a chisel to get down through it, so when the spacecraft is encased in that kind of environment, with no heaters and no power, it’s a very difficult time.”
He added: “The chances of recovering Phoenix are about the same odds as winning the lottery. Firstly, the solar panels may break under the weight of the ice, and once they’re broken there’s no hope. You have to worry about the electronics themselves and whether they are capable of surviving at those temperatures. Then you have to worry about the instruments. So it’s a slim chance – but it’s not zero.”
