LOS ANGELES — NASA declared an end to the Phoenix mission on Monday, some five months after the spacecraft became the first to land in Mars' arctic plains and taste water on another planet.
Mission engineers have not heard from the Phoenix lander in over a week. It fell silent shortly after a raging dust storm blocked sunlight from reaching its solar panels. Although ground controllers will direct two satellites orbiting Mars to listen for Phoenix for several more weeks, the chances that it will respond are slim.
Phoenix's demise was predicted. Unlike its hardy twin rover cousins Spirit and Opportunity, now approaching their fifth year near Mars' more hospitable equatorial region, Phoenix's days were numbered from the outset. With sunlight waning and winter encroaching on the arctic plains, scientists had said it was a matter of time before Phoenix would freeze to death.
Doug McCuistion, who heads Mars exploration at NASA headquarters, said people should view Phoenix's end as "an Irish wake rather than a funeral. … It's certainly been a grand adventure."
The Phoenix mission was not trouble-free. Early on, it was dogged with difficulties involving its tiny test ovens designed to sniff for traces of organic, or carbon-based compounds. Several oven doors failed to open all the way; the lander also had trouble getting the dirt into the ovens, and a short circuit threatened to render the instrument useless.
Phoenix grew considerably weak in recent weeks as the Martian weather deteriorated. It braved plunging surface temperatures and a swirling dust storm that drained its power.
Despite overcoming the oven troubles, Phoenix has not discovered the elusive organic-based compounds essential for simple life forms to emerge. So whether the Phoenix landing site was habitable remains an open question.