Quotes of the Day

There's nothing terribly remarkable about Building 29 at the Johnson Space Center in Houston until you consider that that's where they will be storing Mars—or at least a pretty good facsimile of it. Spread out inside the sprawling structure will soon be a dead-ringer Mars base, complete with habitat modules, an extraterrestrial greenhouse and even a ground cover of volcanic dust shipped in from Hawaii—about as close as you can get to real Martian dirt without actually visiting the planet. Astronauts training for a Mars mission could spend up to 600 days in this little village, learning to live in an unfamiliar world at least 35 million miles from Earth.

This ersatz Mars has been in the works for years, but until now few people have paid much attention to it, largely because nobody realistically expected to set human eyes on the genuine planet anytime soon. As of last week, however, Building 29 could become the center of the universe—or at least the center of NASA's universe. For the first time in a long time, cosmic planners were given reason to hope that after decades of drift, the U.S. is at last back in the space game.

In a move the White House probably saw as an election-year head snapper, President George W. Bush sketched out a long-term vision for manned spaceflight that goes far beyond the dog paddling in near-Earth orbit to which the space agency has confined itself since the 1970s. Back on the table is human exploration of the moon; back on the table is human exploration of Mars.

Swept to the floor—or at least to the side—is the overbudget, underproducing International Space Station and the increasingly creaky, increasingly lethal shuttle fleet.

"Today," Bush said last week before an audience of jump-suited astronauts and NASA scientists, "I announce a new plan to explore space and extend a human presence across our solar system."

Maybe. It's just possible, however, that there's a lot less to the Bush plan than meets the eye—or matches the hype. The President's proposal does not call for any new footprints on the moon until 2015 at the earliest—43 years after the last ones were left. And though the year 2030 was bandied about in the press as a target for putting a man on Mars, the President was careful not to set a date. In 1989 the first President Bush called for a manned Mars landing no later than 2019, then stood back and watched the idea die, as the 30-year time frame—not to mention the $400 billion price tag—discouraged even the heartiest Mars partisans. A landing date 26 years down the line would be an improvement perhaps, but not a terribly meaningful one. While the current President took care to avoid the sticker shock of his father's plan, he might have gone too far in the other direction. The funding he has offered the program so far is just $1 billion spread out over the next five years, plus a reallocation of $11 billion already in the NASA budget—hardly adequate cash for a nation planning to settle the solar system.

The budgetary shake-up has already claimed a victim. The Hubble Space Telescope had been scheduled for a maintenance visit next year by space-shuttle astronauts. Now there is no money for the mission, and after 2010 there will be no shuttle anyway. One of NASA's greatest success stories, Hubble will probably wink out sometime in 2007.

Having rung the Mars bell, however, the current Bush Administration may find it's not possible to unring it. Even if it's true that the President's announcement was nothing more than a bit of election-year candy, it's getting some very serious attention from some very smart people. Mars, they're concluding, is not out of reach for human beings—and it need not take decades to get there. Indeed, there may be any number of possible routes to the Red Planet that could, some say, have boots on the soil in as few as 10 years. All that's needed is the commitment to go—and the institutional maturity to see that commitment through.

"It's not a financial issue," says Bruce Murray, former director of NASA's Jet Propulsion Laboratory (J.P.L.) in Pasadena, Calif. "The NASA budget doesn't have to increase dramatically for this to take place. But we'd have to keep our eye focused on what we're doing for a long time. And that, for Americans, is a new experience."

All the fresh talk about a manned mission to Mars comes during what has been a heady few weeks for the long-struggling NASA. Earlier in the month, the Stardust spacecraft, launched in 1999, made an improbable flyby of Comet Wild-2, drawing in a breath of primordial dust to bring back to Earth for study. In the middle of last week, the Spirit rover—which bounced down on Mars at the beginning of the month—at last rolled off its landing ramp and onto the dry flats of Gusev Crater. As J.P.L. engineers radioed up instructions, the rover prepared to stick its snout in the soil and begin the hunt for signs of ancient water, and with it the hunt for clues to ancient life. Meanwhile, Spirit's sister rover, Opportunity, continues to head for its own landing on the planet on Jan. 24.

But it was the Bush speech that trumped all those triumphs, and that in itself said something. Human beings in a spaceship beat unmanned metal every time, no matter if the metal is up and running and the humans won't fly for years. Even overseas, the speech made news. British bookmakers offered 10-to-1 odds that human beings will not set foot on the moon again before the end of 2015 and 50-to-1 odds against Mars' being reached before 2030 is over. The Chinese had reasons of their own to be interested. On New Year's Day, Beijing announced that it was beginning its own lunar program, with a first unmanned landing set for six years away. The program is called Chang'e, a reference to the story of the lonely Chinese fairy who fled to the moon after stealing her husband's immortality pills. If China's lander cruises anywhere near the U.S. outpost, it may touch off a Sino-U.S. space competition reminiscent of the old U.S.-Soviet space race.

While it's easy for a President to talk about going to Mars in the run-up to an election, it's terribly, terribly hard to get there. Before astronauts can even think of suiting up and taking off, a host of problems have to be solved. The first and most obvious challenge is to design and build a Mars-worthy spacecraft. Winged ships like the shuttle are clearly out—useless in the wispy Martian atmosphere and unreliable even close to home, as two shuttle disasters have shown. That means a return to something closer to the capsule model that served the Mercury, Gemini and Apollo programs so well. Boeing Aerospace has already been designing a podlike crew transfer vehicle to get astronauts to and from the space station and to take a little of the load off the shuttle. The design won a lot of backing in Congress and the space community after the Columbia disaster grounded the entire shuttle fleet. The President's Mars-and-moon plan calls for the development of what is being called a crew exploration vehicle, and a souped-up version of the Boeing craft might do that job nicely.

"The reason you're seeing the Apollo-like configuration come back," says Volker Roth, a Boeing engineer, "is basically its safety and robustness during the first 100 miles and the last 100 miles of any space trip." Such a comparatively simple vehicle could be ready relatively soon, but the loose time frame of the Bush plan doesn't call for the craft to fly before 2014. That decade-away projection puzzles Charles Allen, head of Boeing's Orbital Space Program. "By 2007 we could be doing major systems tests," he says. "I don't see any problem with that."

Far thornier than the design of the spacecraft is the problem posed by all the fuel, food and water such a mission would require. The Apollo flights to the moon were gas-up-and-go trips that lasted no more than 12 days. You could fill the tank and the larder once before you left and carry along everything you would need. Not so when you're looking at 14 months of round-trip flight time between Earth and Mars and perhaps a 11/2-year stay on the planet to catch the next Earth-Mars alignment back home. Even if it were possible to build a ship big enough to carry all that cargo, you would still have to muscle the mammoth thing off the ground. At some point it simply becomes impossible to build a rocket big enough.

The answer is to manufacture a lot of what you need on-site. If any of NASA's unmanned Mars ships do find accessible water on the planet, it will be very big news, and not merely because of what it means for the possibility of Martian life. Martian water, once purified, ought to be as useful for drinking and bathing as earthly water. What's more, since water is merely hydrogen and oxygen and since it's hydrogen that provides the propulsive fire in some liquid-fuel engines and oxygen that keeps those flames burning, breaking the two elements apart in a Mars-based fuel distillery could provide everything necessary to refill the tanks of a spacecraft once it arrives on the Red Planet. Oxygen produced on Mars could also be used as breathable atmosphere.

"One scenario," says John Hoffman, a physicist at the University of Texas at Dallas who is working on a 2007 Mars probe, "is to send rockets up two years before people go, then robotically make water for an 18-month stay and fuel for the return. Only when it's 100% done do you send humans." For mission planners—not to mention astronauts—spooked by the idea of arriving on Mars and finding that the fuel and water tanks have sprung a leak, redundant tanks could store twice as much as needed and provide some margin of safety. If it's possible to make fuel, air and water on-site, it is also possible to grow food. Mars has plenty of soil, and if chemical samplers like those aboard Spirit prove that Mars dust isn't poisonous, it would be a relatively straightforward job to assemble a greenhouse-like enclosure, raise the temperature, pump up the atmosphere and plant a few seeds. Donald Henninger, a NASA chief scientist, has identified 13 crops that could thrive in a space habitat, including wheat, potatoes, soybeans and salad greens. "You can take stored food along, but how long does it last?" he asks.

Molecular biologist Rob Ferl at the University of Florida wants to conduct similar experiments with mustard seeds. "The first generation of experiments would be enclosed in something like the rover," he says. "You'd use a mechanical arm to scoop up dirt and capture sunlight with light tubes." The fact that some of these early experiments could take place with existing technology on future rovers is one reason mission advocates question Bush's long time frame for his Mars flights. "Johnson Space Center was a cow pasture when we started the lunar program," says Humboldt Mandell, a planetary scientist at the University of Texas who managed the last Mars initiative, "and still we got to the moon in seven years from a cold start."

One more head scratcher for at least some people in the space community is the Bush proposal's heavy reliance on the moon as a stopping point on the way to Mars. The President calls for NASA to establish a lunar base first, learn to live and work there, and then use that extraterrestrial space center as a launch facility where Mars craft shipped up from Earth in pieces could be assembled and relaunched.

To be sure, there's something to be said for trying out your hardware and survival skills at a campsite only three days from home as opposed to one seven months distant. Wendell Mendell, Johnson Space Center planetary scientist, worries about the physical and psychological effects of a long Mars mission and agrees that the moon is a good place to try out survival skills. "The attitude is, They're astronauts, they're tough, stick 'em in a tuna can—it doesn't matter," he says. "But it does. That's why the moon is important."

It's true too that the moon may be an appealing launchpad because lunar gravity, just one-sixth that of Earth's, makes payloads a lot lighter and launching them a lot easier. But things aren't quite that simple. An Apollo astronaut confessed that after his lunar module landed on the moon, he had the sobering realization that before he could return home, he would again have to get the ship moving very, very fast. As any astronaut knows, the two most challenging tasks in operating a spacecraft are starting and stopping it. If it's possible to avoid additional stops and starts, it's best to try.

"We can go directly from Earth orbit to Mars, and it would probably be simpler and less costly," says Larry Bell, space architect at the University of Houston. "Some of us don't see the necessity of going to the moon first." There's another concern, one that worries administrators more than engineers. If NASA history has proved anything, administrators say, it's that intermediate space goals can sometimes turn into ends in themselves. "We could easily get bogged down on the moon and never get to Mars, at least not in this century," warns Murray. That kind of long-term detour, says Robert Zubrin, president of the Mars Society and author of The Case for Mars, is "the same swindle we fell for on the space station."

If what Mars planners are really after is a stable, low-gravity place where spacecraft could be assembled and missions could begin, they might do a lot better to fly out to Lagrange point L1—a spot about 200,000 miles from Earth where the gravity of Earth and moon are in relative equilibrium. Gravitational forces essentially cancel each other out at such cosmic odd spots, making them easier to leave than the low-gravity moon and entirely eliminating the need to ease hardware down to the surface and then wrestle it back off again. Once your Mars ship is poised in space—either hovering at Lagrange point L1 or fresh off the surface of the moon—your next worry is the matter of in-space propulsion. Speed is everything on the way to Mars, and not only because a seven-month trip in a confined space can be torturous. The bigger problem is that it can also be lethal because of radiation exposure in deep space, where the absence of Earth's magnetic field leaves astronauts far more exposed to deadly cosmic energy than they are in orbit or on the way to the moon. Some kind of shielding is obviously necessary—anathema to space designers, who like to keep hardware light, but unavoidable all the same. (On the surface of Mars, tanks of water or even dirt berms could serve the same protective purpose.) The best way to limit the radiation dose on the way to Mars is simply to limit the transit time, and that means improving on the conventional engines all spacecraft have carried up until now.

Ion-propulsion engines—in which a portable nuclear reactor heats charged gas and then fires it out the rear of the spacecraft—already exist and are capable of accelerating ships to very high speeds. But the stream of ions the engines produce is a thin one, and even a small ship requires a long time to accelerate—a problem when time is the very thing you're trying to limit. Another possibility is nuclear thermal propulsion, which uses a larger reactor to superheat traditional propellant and blast it out the engine nozzle. Things move a lot faster with such a system, but the engine as a whole is heavier and cruder and the big reactor causes jitters among environmentalists, who would just as soon see nothing nuclear aboard any rocket that could blow up before it leaves the atmosphere. Astronaut Franklin Chang-Diaz says a plasma-propulsion rocket being developed in NASA's labs will go faster still, getting man to Mars in 40 days. Though a decade or more from realization, it uses magnets and abundant gas like hydrogen to produce acceleration.

Perhaps the biggest hole in Bush's speech had to do not with technology but with bureaucracy. It's hard to overstate the stultifying impact the International Space Station has had on NASA since it was first proposed by Ronald Reagan in 1984. The project—advertised initially at $8 billion—is woefully behind schedule and nowhere near completion, and may well cross the $100 billion mark before it's done. No one realistically pretends that any commercial manufacturing will ever take place aboard the thing—a key selling point 20 years ago. Nor can there be much research on the effects of long-term spaceflight on human health—not with the small crews and relatively short stays the station can accommodate. Its current crew does little with its time but maintain hardware and fix problems, the latest being a worrisome oxygen leak that has so far bled away 4% of the station's air since it sprang in late December.

The fact that the Bush proposal didn't kill the orbiting cash hog outright may be because it can't be killed. With contractors and subcontractors across 22 states and uncounted electoral constituencies, the station has long been a kind of cunningly planted political kudzu, impossible to pull out stem and root. If domestic commitments didn't lock the station in place, commitments to NASA's 15 international partners certainly do. And while the station thrives, so too must the three living shuttles, since they exist largely to ferry up parts and crews. "The space station is a failed dream of the '60s and '70s," says Murray. "It's a monument to the past, as is the shuttle."

The six years remaining before the most recent—and possibly still unreliable—target date for the station's completion means six more years of money and labor poured into the seemingly endless project. With shuttle and station operations consuming about 40% of NASA's $15.5 billion annual budget, it's no wonder the President's moon-and-Mars plan calls for no new component to fly until 2014. It's only then that the real spending—perhaps $170 billion, according to NASA's estimates, and probably much more—could begin. So what would it take to move the Bush proposal—or any other moon-and-Mars proposal—out of the blueprint stage and into space? For one thing, it would take a real commitment. Remember the national aerospace plane? No? Neither does anyone else, but this was one of the start-and-stop projects on which NASA lavished dead-end research dollars in the 1980s. "From 1961 to 1973," says Zubrin, "we had Mercury, Gemini, Apollo, Skylab, Ranger, Mariner, Surveyor, and we developed almost all the space technology we have today. What did we accomplish in the '90s? We flew half-a-dozen robotic probes and 60 shuttle missions."

The difference between the NASA of that golden age and the NASA of today is that the old agency had one principal goal—the moon—and remained monomaniacally focused on it through 11 years, six Congresses and three presidential administrations. The current plan will take more than twice as long to play out, dithers between two dramatically different destinations and doesn't get rolling in any real way until 2010, when the shuttles are finally put to sleep. Says Zubrin: "The schedule is the first red flag. We could go to Mars in six years if we really wanted to."

By even the sunniest scenarios, six years is probably way too fast. No matter how long it takes, however, if human beings are going to make—and fulfill—a commitment to walk on the Red Planet, our biggest shift will have to be a philosophical one. Both NASA and the politicians who keep it funded have spent more than 40 years explaining why the agency exists at all, justifying the expense with a lot of talk about science and spin-offs and educational dividends. They're telling the truth when they make those claims, but only some of it. People don't hold parades for a manufacturing spin-off, and they don't muffle their drums and lower their flags when an educational program dies. They do that for astronauts—men and women in puffy suits who climb on top of 30 stories of exploding stuff and ride it to places none of the rest of us will ever get to see. That's the most compelling reason we spend the money we spend. Bush nodded in that direction in his speech last week, but it was only that—a nod. It will take something closer to an embrace to get us all the way to Mars.

—Reported by Cathy Booth Thomas/ Johnson Space Center, Dan Cray/ Los Angeles, Hilary Hylton/Austin, Broward Liston/ Cape Canaveral, Eric Roston/Washington, Frank Sikora/ Birmingham, Maryann Bird/ London and Matthew Forney/ Beijing

• Jeffrey Kluger