Lunar homes: Tiny rooms, but they repel dust and solar storms
HOUSTON — Within 25 years, the Home and Garden Channel may need to add some new entries to its lineup, shows like "Designing for the Space Suits" and "Moonscapers Challenge."
While the National Aeronautics and Space Administration prepares to finish building the space station, a small team of architects and engineers here at the Johnson Space Center is exploring designs for living and working quarters on the moon and beyond.
At this point, future occupants of Rancho Luna can select from any style module they want, as long as it's a tube. Ultimately, habitats may include multistory vertical tubes as well as simpler horizontal ones, designers say. For now, they are working with astronauts who have spent months in tight quarters to learn how to make a lunar outpost livable, if not lovable.
The ideas are taking shape in plywood and foam board to test everything from the optimal size of crew quarters to the desirability of putting a half bath close to the air lock for last-minute pit stops before the crew suits up.
As with the push to finish the space station and retire the shuttles by 2010, the driving force behind the effort is President Bush's vision for space exploration. While fresh US bootprints on the moon aren't expected to appear for more than a decade, it's not too early to think about where astronauts will stay for long- duration visits, says Larry Toups, who heads the effort at the space center's Advanced Projects Office.
"Over the course of the next five years or so, we'll be using very low-tech things" to identify future needs, he says. These needs are as vital as radiation shielding and dust control, and as mundane as whether to include exercise treadmills.
When the center's health gurus found out that Mr. Toups's team was building mock-ups, they brought over exercise equipment. After all, the space station has exercise gear to help astronauts blunt the effects of weightlessness.
But on the moon, Toups points out, gravity – as low as it is – means moonwalks will be more strenuous than spacewalks, where everything is weightless. "The debate becomes: Do we really need this amount of equipment? Won't they be getting exercise based on their EVAs?" he asks. If such extra-vehicular activity isn't enough, must exercise equipment be stowed immediately after use or should the living space be designed to allow astronauts to leave it out?
"I don't know how you are at home, but usually when something gets pulled out" in many homes, "it stays that way," he adds. "We're using the mock-ups to drive those kinds of discussions. That's the value that you get."
For those who don't demand a panoramic view of, say, the Mare Imbrium, Toups's colleague George Rains is pleased to show a hori-zontal version of a habitat module, complete with life-size photos of equipment racks hanging on the walls. Like a low-key realtor exploring possibilities with prospective buyers, he walks a small group of visitors through the two-floor tube, which measures 37 feet long and 15 feet in diameter. It's 9 feet longer and a foot wider than the main space-station modules.
"We're using this for dimensional studies," he says as he points to four variations on crew quarters – ranging from 221 cubic feet to 418 cubic feet in volume. In this configuration, the crew would live upstairs. The galley, commons area, life-support equipment, and an airlock large enough for four space-suited astronauts occupy the ground floor.
One concern, Mr. Rains points out, is moon dust. On Earth, dust particles' naturally sharp edges are rounded by wind and water. On the moon, the dust is more destructive. "It's like finely ground glass," he says. Thus, it's vital to keep the dust at bay.
One approach, incorporated in this mock-up, is to use raised thresholds, simi-lar to those found aboard ships. Controls also might include something as relatively complex as maintaining slightly different air pressure in rooms adjacent to the air lock. Or it could be as simple as a grate on the floor, where incoming crews would scrape their boots.
Over in Hanger X, at the far end of the space center's campus, Toups unveils a mock-up for outpost crews who want something more akin to a townhouse. Roughly 23 feet across and some 30 feet tall, the cylindrical mock-up is designed to explore the possibilities of vertical living. The ground floor might contain the life-support and power systems, plus storage and a docking port for resupply capsules. The crew's common area, galley, and food storage occupy the second floor. The third floor is the crew's quarters.
So far, the only simulated furniture appears on a floor plan tacked to the wall.
"One issue we need to deal with is vertical translation," Toups says – NASA-speak for ways of getting people and supplies up and down the module. Currently, a Navy-style ship's ladder joins the second and third floors; a more user-friendly design is still undecided.
A key concern is shielding the crew from radiation, which comes when the sun erupts in flares and other violent outbursts.
"That problem is not trivial," he says, noting that an individual solar storm can last up to four days. If a crew member is caught outside, he or she may have to rely on geological features like ancient lava tubes or crater walls for shelter. To protect the habitats from radiation, Toups's team is exploring options ranging from sandbags filled with lunar soil to placing water tanks and large pieces of hardware along the interior perimeter of the structure.
In the end, however, the habitats also will need something intangible: the feeling that the module is home. That's a challenge to any space architect.
"You need all this high-tech stuff to provide the environment," Toups says. But at the end of a crew's long day on the hostile lunar surface, "what they will want when they get in and shake off all the dust, is to feel like: 'This is where I live.' ... It's like that log cabin in the woods in winter – there's a glow inside, there's a fire, you go inside and go: 'Ah, I can sleep here at night.' "