By 6:45 on a chilly desert evening, a deep indigo sky has squeezed what remains of the day into thin lines of pink and turquoise twilight along the horizon.
Satisfied with nightfall's progress, NASA engineer Joe Kosmo gives the word, and his crew begins to pressurize a spacesuit glistening under a floodlit canopy.
Tonight's objective: to test new helmet lights to see how effectively they might illuminate an astronaut's path.
If you've ever wondered how exploration equipment makes its way into space, welcome to the rolling flanks of Arizona's famed meteor crater. For two weeks a year, this stark landscape becomes a surrogate planet - a place where a small team of scientists from the National Aeronautics and Space Administration drive a futuristic electric tractor, guide small robotic "scouts," and test an array of other gear astronauts may need in their cosmic garages for future explorations of the moon and Mars.
Disclaimer: These machines aren't ready for prime time. Stuck with a Kmart budget, the NASA team builds much of its hardware from off-the-shelf parts, space-center castoffs, and junkyard finds.
The chassis for their electric tractor? Reclaimed from a discarded all-terrain vehicle. Shock absorbers for the vehicles? Culled from junked motorcycles. Engineers bought a digital microscope for one of the rolling geology labs from a department store toy section. And the crew fashioned a unique scoop out of a discarded desk-lamp shade.
"We've done this on a shoestring," says Dr. Kosmo, a 43-year veteran of the space program and the senior project manager for the Desert Research and Technology team, aka the Desert Rats. The team, based at NASA's Johnson Space Center in Houston, makes its annual trek here to test concepts with prototypes. "You can only do so much in the laboratory," Kosmo adds.
Driving the effort is a simple fact: Exploring planet surfaces is a lot different - and more physically demanding - than spacewalks. During each of the final three Apollo missions, for example, astronauts spent three days on the moon gathering samples. A seven- to eight-hour trek on the lunar surface actually could turn into a 10- to 12-hour workday after including time spent suiting up and preparing the spacesuits for the next day's outing, notes John Gruener, a flight-systems engineer at the Johnson Space Center. At the end of those three days, "the astronauts were just worn out."
"The big challenge for us is how to make extra- vehicular activities routine," Mr. Gruener says. "We're talking about astronauts going out three or four days a week for four to five weeks at a time. There's a real concern you're going to wear out the crew."
To avoid that prospect, NASA is designing lighter, more-flexible spacesuits whose air and cooling systems can be replenished in the field. It also is developing work methods and tools that reduce the astronauts' exertions, which in turn determine how quickly they use up those "expendables."
The desert tests are especially important now that NASA has a cadre of mission controllers who never have experienced an Apollo-era lunar exploration.
"We've got a whole generation of flight controllers who know nothing but the shuttle and the international space station," says Dean Eppler, a geologist who is serving as the projects' faux astronaut, known formally as a "suit subject." "They've had no experience at planetary operations like Apollo."
With that in mind, the Desert Rats are linked via satellite to an experimental mission-control center in Houston to begin rebuilding that expertise.
This is the seventh year the group has brought the fruits of its labor into the field. Each year's agenda builds on the lessons gleaned - often the hard way - from prior years.
By all accounts, this year's is the most successful outing yet. The only glitch came on the last day, when Dr. Eppler's space suit lost pressure prematurely, making it too cumbersome to operate. The malfunction cut short the "spacewalk" portion of a Web and satellite broadcast to students nationwide, forcing the program's emcee to pull anyone in an orange NASA jumpsuit in front of the camera to describe their role and backgrounds.
Besides the spacesuit, this year's cast of mechanical characters includes:
• Mathilda, a small robotic rover.
• The solar-charged electric tractor, which looks like a candidate for a Nieman-Marcus catalog, with a winch, a small bulldozer blade, and trailer hitch.
• Mobile geology labs, which allow scientists to make preliminary tests of interesting rocks where they find them.
• A small aluminum chariot with its own trailer hitch that serves as a platform so the astronaut can drive a chain of vehicles around the site.
• A sitewide wireless communications network for computers and voice, which a group from NASA's Glenn Research Center in Cleveland is testing as a kind of wi-fi network for other worlds.
In an era of high-tech glitz, the focus needs to fall on simplicity and reliability, says Eppler. "When we test this stuff with the spacesuit, we're asking: 'Is the workload acceptable?' Or is this something where we say: 'We really don't want to do it this way?' "
For example, the team tested two approaches for controlling its electric tractor. One used a hobbyists' hand-held radio-control transmitter with a pair of joysticks; the other, a pair of switches built into the spacesuit and connected to the controller. The hand-held transmitter won, hands down. An astronaut could steer the tractor while walking beside it or mount the controller on the chariot itself and ride along, while steering it.
How simple does the technology have to be?
Technician Bill Welch beckons a colleague and this reporter to each take a turn at the joysticks of the tractor. "Lean into the front rail," he advises as I step onto the chariot. "That way you won't lose your balance when you run over rocks." Was that a vote of no confidence in my driving ability, or merely terrain-savvy advice?
My colleague makes a flawless circuit of the small test course. I nearly match that performance, but at the last minute I snag the tractor's bulldozing blade on a rock. I'm sure I'd do better on Mars.
Contrary to popular belief, Tang, Velcro, and Teflon were not developed by NASA, but were linked to the US space agency by corporate marketers. Still, space research has created more than 30,000 spin-off technologies - from practical inventions like smoke detectors, bar codes, and cordless drills to more unusual items. Among the latter group:
• Fragrances for Shiseido perfume and Unilever body spray were taken from flowers grown in space.
• Scratch-resistant coatings for eyeglass lenses were derived from the helmets of astronauts' visors.
• Submarine fire extinguisher (under development) uses mist rather than a jet of water. It could fight a spacecraft - or sub - fire without damaging sensitive equipment.
• Rock-lined fuel tank (under development) would use zeolite crystals to store hydrogen in its liquid state without expensive freezing technology, making hydrogen cars more feasible.