June 24, 2008
Moon Trekkers Try Moses Lake
MOSES LAKE SAND DUNES, Wash.-- This patch of desert may resemble the moon, but a team of NASA scientists who came here to test lunar robots, rovers and spacesuits found spring weather in Eastern Washington can be worse than outer space.
During the two-week exercise, howling wind blasted sand into every nook and crevice of the machines _ some of which were venturing outside the lab for the first time. Rain squalls forced scientists to shield state-of-the-art prototypes under blue tarps."It has been pretty bad," said project coordinator Bill Bluethmann, rubbing his eyes with his knuckles as waves of dust rolled through like breakers on a shore. It never rains on the moon, nor is there wind in the airless lunar "atmosphere," he pointed out.
But moon dust kicked up by astronauts, rockets and rovers can damage gear, as the Apollo program showed. One of the main reasons NASA picked Moses Lake from a list of 20 potential field sites was the fact that local soils resemble those on the moon, Bluethmann said. The engineers also liked the combination of flat, open terrain and rolling dunes in the 3,000-acre off-road-vehicle park where they set up shop.
"It's got a lot of lunar qualities to it." Bluethmann said.
The field tests are part of NASA's preparations for a manned moon mission in 2020. America's return to the moon after more than 35 years is part of President Bush's ambitious space strategy, which includes establishment of lunar outposts as a steppingstone to Mars.
While lawmakers and scientists debate the wisdom of the $230 billion venture, the space agency is forging ahead on a new generation of robotic tools to help astronauts maneuver and work on the lunar surface.
Several of the most promising designs were being put through their paces recently in a scene reminiscent of a sci-fi movie set.
Playing the role of the diminutive 'bot sidekick was something called the K-10. Trailed by two researchers who towered over it, the 3-foot-tall machine zipped around the dunes, using cameras, ground-penetrating radar and 3-D scanning lasers to map the terrain.
Putting in a cameo as the workhorse robot was a 30-foot-tall experimental crane. Swinging its arms like a giant praying mantis, the machine lowered boxes from a high platform to simulate the job of unloading gear from a lunar lander.
But all eyes turned when the gleaming star of the show rolled into view. With room for two astronauts, the 12-wheeled lunar truck called Chariot is a leading candidate for the moon rover of the future. Each set of wheels pivots independently. The pilots stand, strapped into turrets that eliminate the need to sit down _ something very tough to do in a spacesuit. The gold and white truck can move forward, backward and sideways like a crab. Top speed is about 15 mph.
The vehicle was originally equipped with knobby tires, Bluethmann said. But the scientists swapped them out for smooth versions at the suggestion of a local farmer familiar with the sandy terrain.
"We bought them here," said Bluethmann, who works on the Chariot project at Johnson Space Center in Houston. "They've performed very well."
Julie Townsend, an aerospace engineer from NASA's Jet Propulsion Lab in Pasadena, Calif., was also pleased with the performance of the lunar RV she helped design.
Called ATHLETE (All-Terrain Hex-Legged Extra-Terrestrial Explorer), the six-legged vehicle sits low to the ground like a spider and carries living quarters for astronauts on its back.
During the Apollo missions, exploration was limited because the astronauts always had to retreat back to the lunar module, Townsend explained.
"If you have a mobile habitat, you can travel and explore more of the moon."
Under a program called "Desert Rats," NASA has been field-testing gear and spacesuits for years at desolate locations from the Canadian Arctic to Death Valley. The agency also has been to Washington state before, using the coulees and dry waterfalls of the Channeled Scablands _ gouged out by ancient floods _ as a model for Mars.
Craig Bernard, a NASA spacesuit engineer and veteran desert rat, tested hard-bodied and soft-bodied suits during the Moses Lake exercises.
The famous film of Neil Armstrong's "one small step" shows the shortcomings of the early spacesuits, Bernard said: The stiff-legged gait was caused by pressurized suits that didn't bend well at the knees. Astronauts occasionally toppled over backward in the clumsy suits, which were not reusable or designed for regular maintenance.
"Our goal is to understand how to get a more mobile suit for the next mission to the moon," Bernard said.
Several NASA workers donned the suits during the field test to try them out on the lunar truck and other gear. It's a hot, grueling job to wear a 240-pound suit in Earth's gravity, said Bernard, who is excluded from the duty because his feet are too big.
But he may have been the NASA engineer least fazed by the blowing dust of Eastern Washington.
Abrasive grit ate away at zippers and fittings on the Apollo spacesuits, Bernard explained. So the more engineers can learn about dust damage and how to prevent it, the better, he said in the command-post trailer, where the spacesuits hung on custom racks.
"Dust got in everywhere," he said happily.