A Condo on The Moon...

By Jeffrey Kluger

It's getting hard to find many Americans who remember where they were the last time men set foot on the moon. Not only had most of us quit paying attention to lunar landings by then, but 48% of us hadn't even been born by December 1972, when the last moon walkers left the lunar surface and headed for home.

But the U.S. may be bound for deep space again. In a rare double hit of good-news headlines last week, NASA announced first that it has firmed up its plans for America's return to the moon and then, two days later, that it had discovered signs that water had flowed on the surface of Mars within the past seven years. Where there is water, of course, there could be life.

For space watchers, these are game changers. In the three years since President George W. Bush announced his plan to send Americans back to the moon and on to Mars, questions have persisted about whether NASA has the institutional wherewithal to pull off so grand a plan and whether there's enough scientific rationale to even try. But now there's reason for optimism on both fronts.

The first encouraging sign that NASA means business is the sensible hardware it's envisioning for the lunar portion of the moon-Mars program. The new vehicles are based on proven--if souped up--Apollo technology, with an orbiter that looks a lot like the old Apollo command module and a lander that resembles the familiar spindly lunar module. The new lander could carry three or more crew members down to the surface and drive them around the lunar landscape, doubling as a sort of extraterrestrial pickup truck. Crews would live for up to 180 days at a time in trailer-like pressurized modules similar to those used aboard the International Space Station. "We're looking at something that can grow without a lot of redesign," says Doug Cooke, leader of the NASA study group that developed the plan.

The site for the moon settlement is uncertain, but the best candidate is near Shackleton Crater at the south lunar pole. Parts of the region are bathed in sunlight more than 70% of the time, just the thing for the outpost's solar panels. What's more, ridges and hills cast patches of ground in equally deep shadow, meaning a possible supply of ice that could be used for drinking water and hydrogen and oxygen fuel.

Astronauts who set up camp at the site would have a lot to keep them busy. NASA is exploring 180 areas of scientific research and other projects for its moon crews, from the lofty (solar physics) to the frankly commercial (installing lunar robots that could be driven remotely from Earth by paying customers to help defray costs.)

So what's not to like? For starters, the timeline. Earth-orbit tests of the vehicles would not take place until 2014; the first landing is planned for 2020, with the outpost to follow in 2024. That's a lot of Congresses and presidential administrations that would need to stay focused. Then there's the money. NASA's annual budget is a relatively modest $17 billion, and the new plans are based on the assumption that the figure will not rise appreciably. Things should get easier in 2010, when the aging shuttles are mothballed, freeing up perhaps $6 billion annually. But NASA's history of cost overruns is no better than the rest of the government's--which is to say lousy.

Still, space officials insist they're wise to their own worst tendencies. "We will go as we can afford to pay," says deputy administrator Shana Dale. "Our charge is to build a program that is sustainable." One indication that NASA takes this seriously is that the equipment being developed for lunar exploration is intended to be adaptable to Mars exploration as well, eliminating the cost of entirely retooling when there's a shift to a more distant, less hospitable destination.

The allure of that second destination got a big boost with last week's discovery of fresh signs of water on Mars. It was made by the Mars Global Surveyor, a spacecraft that has been in Martian orbit since 1997 and finally winked out only last month. Before it did, it produced exhaustive photographic maps of the planet, including shots of tens of thousands of now dry gullies that were almost certainly carved by water. Most of those channels haven't changed over time, but at two of the sites investigators found what appear to be the tracks of flows that occurred within just the past seven years. "It would be about five to 10 swimming pools' worth of water at both sites," said Ken Edgett, a senior scientist for the Surveyor project and a co-author of the new report.

If water was indeed the cause of the tracks, the likeliest source would be aquifers just below the surface. But while this conjures images of warm, amniotic pools cooking up all manner of biology, Michael Malin, chief scientist of the study, urges caution. Acids mixing with water can lower its freezing temperature to nearly -150DEGF. That's a cold, caustic brew for any living thing that tries to take hold. "Water on Mars does not prove biology," Malin says, "but it may permit it."

Even that makes Mars a far more fertile place than it once seemed, and for many space scientists, that's a good enough reason to go. Lack of funding or political will may yet scuttle the entire audacious moon-Mars enterprise. But for now at least, it appears that a human species that has kept itself confined to the home planet for the past 34 years may once again begin moving stepwise through the solar system.