Before its demise it confirmed the presence of water at the red planet’s North Pole, sent back more than 25,000 photos and accumulated a trove of data that scientists are only just beginning to analyze.
The mission accomplished “99 percent of what we proposed to do,” principle investigator Peter Smith, of the University of Arizona, told National Geographic News.
And at a press conference marking the end of the mission, scientists were upbeat.
“It’s really an Irish wake, rather than a funeral,” NASA Mars Exploration Program director Doug McCuistion said. “We should celebrate what Phoenix has done and what the team has done.”
Phoenix launched on August 4, 2007 and touched down on Mars on May 25, 2008. It was the sixth probe to visit on the planet, but the first to land at its North Pole.
Scientists lost contact with the lander Nov. 2, after a dust storm clouded the sky and blocked the light Phoenix needed to power its solar panels. The mission’s planners had expected the lander to fail soon anyway, though, as the North Pole’s short winter days meant little light would soon be available anyway, and temperatures at the Pole dropped to their winter lows of -240 to -300 degrees Fahrenheit.
Scientists said they would try to contact the lander for three more weeks, but considered the mission complete.
During its five months on Mars, Phoenix confirmed what scientists had long suspected from satellite orbiter images — that water ice lay just under the Martian soil at the North Pole.
It also found that the soil was alkaline, not acidic as on other parts of Mars, and it discovered traces of perchlorates, chemicals that can be toxic in high concentrations but are also a food source for some microbes. Near the end of its mission, Phoenix took pictures of snow falling on the surface of Mars.
Principle investigator Smith told Reuters that scientists are still poring over other data from the craft to look for signs of past or present life on the planet.
“I’m not sure we didn’t find organics,” he said. “We haven’t analyzed the data yet. These are subtle signatures and until we actually do the work, I can’t say we didn’t find it.”