With the waning of the Martian summer, electrical power to NASA's Phoenix lander has begun to decline, putting scientists into a race to finish their experiments before the dark and cold of winter ends the mission.
“We're now at the point … where we have to struggle to do each of the things we need to do,” said Barry Goldstein, the Phoenix project manager at the Jet Propulsion Laboratory in California.
Goldstein emphasized that scientists were confident they could complete the remaining projects before the lander runs out of power, currently expected in November.
But the increasingly early sunsets have underscored the fact that Phoenix carried a death sentence when it landed near Mars' north pole May 25.
Phoenix's central mission has been to test the soils and water at the pole to determine whether the planet was once, or still might be, habitable for rudimentary life forms.
One of its key tasks has been to test Martian ice for various chemical compounds in its thermal and evolved-gas analyzer.
In particular, scientists want to know the levels of hydrogen and deuterium in the water, which indicate how it was formed and under what conditions, said William Boynton of the University of Arizona.
As the end approaches, Phoenix will become a simple weather station, because checking wind speed and temperature uses the least energy of any of the instruments.