Washington, July 12 : The Mars Phoenix Lander is having a difficult time digging through the tough ice at the planet's north pole to collect a usable ice sample for analysis, and mission scientists have compared the digging to scraping a sidewalk.
According to a report in National Geographic News, mission scientists have said that they expected the icy landscape to be extremely solid and that the lander is equipped for the job.
"Anytime you work with robots in a different kind of environment, there are going to end up being surprises you have to be wary of," said Bill Farrand, of the Boulder, Colorado-based Space Science Institute. "That's part of the process of exploration," he added.
During tests earlier this week, two scrapers on Phoenix's robotic backhoe succeeded in creating piles of soil and ice particles in the bottom of the trench nicknamed "Snow White."
But the fragments were too small to be collected by the lander's scoop-an operation that NASA engineer Richard Volpe likened in a press statement to "trying to pick up dust with a dustpan but without a broom."
Now the team is preparing to use a drill-like rasp to grind up ice and kick it into the scoop for delivery to the TEGA.
"We knew it was going to be really tough. We put (the drill) into the design on the assumption that we'd need it, and as it turns out, we do," said Barry Goldstein, project manager for the Phoenix Mars Mission.
Goldstein also stressed that the rasp can work quickly, digging and delivering a sample to the oven in about an hour.
"That's important, because if it has water ice in it, we want to avoid (that ice) disappearing between the time we acquire it and we deposit it in the TEGA," he said.
Digging is not the only thing that has proven difficult. TEGA itself has encountered some snags-including a short circuit that may threaten its operation.
The short likely occurred when the first Martian soil sample was placed in the TEGA. Because the soil was clumpier than expected, the spacecraft had to vibrate for several days to sift a sample into the oven.
Principal investigator Peter Smith, of the University of Arizona, has said that the oven could short circuit again at any time, so his team is working under the assumption that the next sample delivered to the oven is "possibly our last."