After troubleshooting an electrical problem on NASA’s Phoenix lander and performing a test scoop into the crumbly surface of the martian northern plain, scientists said Monday that they are ready to dig for ice as early as today.
Phoenix is the first spacecraft designed to sample the water on an alien planet. Over the weekend, it sent back images showing white streaks under the lander that could be surface ice.
Scientists were so excited that they nicknamed the site Holy Cow.
“It’s a thrill for me to find out we’re in a really great place to do the science we want to do,” said University of Arizona’s Peter Smith, the lead scientist on the $420 million mission.
Even if the patches turn out to be a more common salt, scientists are certain large stores of ice lie just inches beneath the lander.
Phoenix, which arrived on Mars on May 25, is managed by the Jet Propulsion Laboratory in La Canada Flintridge, Calif.
The $457 million craft was built by Lockheed Martin Space Systems engineers at Jefferson County’s Waterton Canyon plant.
Scientists tested Phoenix’s nearly 8-foot-long robotic arm by extending it to the ground, leaving an imprint that researchers dubbed Yeti (in other words, abominable snowman) because it resembles a large footprint. The arm also scooped up a bit of soil.
“The soil is crumbly,” said Raymond Arvidson of Washington University in St. Louis during a briefing Monday morning from Tucson. “It’s kind of like cemented garden soil.”
He said the robotic arm should not have any trouble digging into it.
“When you push on it, it breaks apart. It’s not going to be really strong stuff,” he said.
The real excavation work is expected to begin as early as today.
Scientists are targeting three sites adjacent to the lander that they have dubbed Baby Bear, Mama Bear and Papa Bear.
Each soil sample will undergo a four-day regimen of testing in the lander’s instruments, with the samples being heated to ever-higher temperatures and the vapors measured to identify the constituents. The science team primarily is looking for organic compounds — those containing carbon and hydrogen.
A potentially serious problem with one of the main instruments, the Thermal and Evolved Gas Analyzer, or TEGA, cropped up several days ago in the form of an electrical short on a filament that uses a magnetic field to charge particles for analysis in Phoenix’s mass spectrometer.
Without this instrument, Phoenix could have been crippled before it started its work.
Engineers switched to a backup. “It was successful,” Smith said. “TEGA is ready to go and perform the science on the soil.”
If the white patches under the lander are not ice, it probably will mean they are a kind of salt called kieserite.
The National Aeronautics and Space Administration’s two Viking missions that landed in 1976 turned up kieserite, which often is left by the evaporation of thin films of water. The finding was one of several that led scientists at that time to declare Mars inhospitable to life. NASA’s Spirit rover, now operating closer to the equator, also has uncovered the salt.
Despite the thumbs-down verdict rendered on Mars by the Viking missions, planetary scientists have speculated in recent years that conditions might exist at some locations for rudimentary forms of life such as bacteria to get a start. All of these scenarios involve water, which on Earth is not only nourishment but a prime medium for life.
