Courtesy of the European Space Agency
THE BIG GUN Night falls on the latest, most powerful version of Europe's Ariane 5 rocket, being readied for liftoff from the Guiana Space Centre off the northern coast of South America. The rocket has two solid-fuel boosters and a main tank that carries 173 tons of liquid oxygen and hydrogen. That fuel is fed into the new Vulcain 2 engine—the engine that may carry European astronauts to Mars.
At six foot two, André Kuipers does not necessarily stand out among his dutch compatriots at a cocktail party, but as an astronaut he is a giant. He is also something of a hometown hero in the Netherlands. Kuipers is one of 13 European astronauts who proudly work alongside their American and Russian colleagues on the International Space Station. In his most recent assignment, he spent nine days aboard the station and performed nearly two dozen science, engineering, and education experiments.
Kuipers's journey to the station and back was rather less than heroic, however. He had to ride aboard a cramped, Soviet-designed Soyuz capsule, his knees almost touching his chest. He did not mind the tight quarters as much as the knowledge that the capsule's navigation system sometimes goes on the fritz. When that happens on the descent, the capsule shifts into an automatic corkscrew pattern, which puts a whopping 8 g's on the three astronauts stuffed inside. Even the Soyuz's normal 4-g plunge is enough to make a hardened test pilot uncomfortable. Kuipers experienced 8 g's on a military jet during training, and he remembers having particular trouble doing two things: staying conscious and breathing.
To Kuipers and many other aspiring explorers within the European Space Agency, this odd mixture of inspiration and indignity suggests that the time has come for the agency to aim higher. Working with a modest budget of less than $4 billion a year—a fourth of what NASA spends—the ESA has already made itself a powerhouse in unmanned space missions. The Ariane 4 rocket was one of the most reliable ever built; its successor, the Ariane 5, is among the most powerful. Last January, ESA's Huygens probe executed a deft descent to the surface of Saturn's methane-shrouded moon, Titan. The agency's Smart-1 spacecraft, currently conducting a survey of our moon, sports a pathbreaking ion-propulsion engine. What the Europeans do not have is a shuttlelike orbiter or Apollo-like crew capsule to place atop the Ariane 5. But that, too, is coming.
As ESA engineers begin building a giant cargo vessel for large loads going to and from the space station, they are also looking at how it can be adapted to carry astronauts and become Europe's first manned spacecraft. The Europeans are also negotiating with Russia to collaborate on the Clipper space plane, currently under development. It is designed to carry a six-person crew to low Earth orbit. The ESA Council has recently approved the Aurora program, a plan for a succession of increasingly bold expeditions, including a robotic Mars sample return mission, a manned trip to the moon, and a manned voyage to Mars in 2033. "Europeans take great pride in seeing our astronauts in space," says Daniel Sacotte, ESA's director of human spaceflight, microgravity, and exploration. "The exploration of space is a high priority."
A lot of the new can-do attitude in the European space program is about symbolism. European nations have struggled for decades to fashion a coherent political union that wields influence on the world stage on a par with the United States. The European Union's disparate and ancient nations have succeeded in competing economically in recent years but have failed so far to find political common ground, as demonstrated by last spring's defeat of the European constitution. What the politicians have tried to do is to get all Europeans—from English bankers to Polish farmers—to think of themselves as a single people. That effort might get a big boost from a shared, inspirational goal, like putting a human on Mars on a spaceship bearing the European logo.
Mars is not an impossible dream for ESA. Airbus and Ariane have established Europe as a big player in the aerospace industry. Meanwhile, the Europeans' main competitors face plenty of troubles of their own. NASA's budgets are woefully underfunded for a manned mission to the Red Planet, and Russia has been struggling to cope with problems more urgent than space exploration. Although China has succeeded where Europe has not by placing a man in orbit, its overall program remains far less technologically sophisticated than ESA's.
The main obstacle to Europe's grand plans is money. Squabbling among member nations has strained ESA's budget, forcing it to create dual-purpose programs, such as a space station cargo module that could eventually double as a crew orbiter for European astronauts. The program, called Aurora, which is supposed to get ESA to Mars, has only $1 billion to spend between now and 2010. To realize its complex and demanding goals, Europe will either have to invest more or collaborate with other space-faring nations, which could include Russia, China, Japan, Canada, India, and of course, the United States.
Europe's strategy to wean itself from its reliance on NASA and the Russian Space Agency goes back at least four decades, to the earliest engineering efforts that led up to the development of the first Ariane rocket. Sacotte, at the time a minor official at the French Space Ministry, recalls a 1970s visit by James Fletcher,
THE FERRY INTO SPACE (CARGO ONLY, FOR NOW)
These two views show Europe's new space-cargo carrier, the Jules Verne, undergoing testing at the European Space Research and Technology Center in Noordwijk in the Netherlands. It will be exposed to extreme heat and cold, vibration, radiation, and vacuum to make sure the design is robust. In one view (above) the carrier's avionics module is exposed.
Meanwhile, a scale model of the cargo carrier undergoes shake tests (above) to simulate the effects of a rocket launch. The Jules Verne will fit atop an Ariane rocket and carry supplies to the International Space Station, freeing the Europeans from their dependence on NASA's space shuttle and Russia's Progress supply ship. With some significant modifications, this basic design could incorporate a crew capsule to carry astronauts to Earth orbit, to the moon, and beyond.
then director of NASA: "He came to Paris and asked why France felt the need to develop its own launchers. He said, 'We have the space shuttle. Isn't that enough for the world?' " In 1986 the space shuttle Challenger exploded 73 seconds after launch, killing everyone aboard. As NASA practically came to a standstill, France, under the banner of the newly formed ESA, moved ahead with a second generation of the successful Ariane.
Now NASA is again in the doldrums, and Europe still lacks the capability to launch its own crew. Sacotte and other ESA officials can barely hide their frustration—not only with NASA but with themselves for not having moved more quickly to build their own astronaut vehicle. By now, European astronauts had hoped to be established in their space laboratory called Columbus, where they would be melting and solidifying conductive metals, studying microgravity effects on single-celled organisms, investigating human balance disorders, and carrying out dozens of other experiments. When the space shuttle Columbia disintegrated during reentry in February 2003, Columbus was waiting to be prepped at the Kennedy Space Center. It's still waiting, under wraps. Although Europe has the potent Ariane 5 rocket, it needs the space shuttle's sizable cargo bay to loft the 20,000-pound Columbus module. NASA's continuing problem with foam shedding from the shuttle's main fuel tank has delayed a follow-up to last August's flight of Discovery. Columbus still does not even have a target launch date.
President George W. Bush raised the competitive stakes in space with a speech he gave on January 15, 2004. Citing the spirit of Lewis and Clark, he announced a plan to send people back to the moon and said, "The desire to explore and understand is part of our character." Then he asked "other nations to join us on this journey, in a spirit of cooperation and friendship." Some Europeans saw in his words a new American quest for hegemony in space, if not a swipe at the Chinese, who have made no bones about their desire to establish lunar colonies. But the announcement oddly echoed the sentiment behind the Aurora program. The executive summary of the first Aurora planning document states, "The desire to explore is a fundamental heritage of the European people."
A foretaste of looming rivalry brings out the alpha-male instincts of the soft-spoken Sacotte. Europe, he says, no longer looks to commercial spin-offs of the research on the International Space Station as its primary motivation for sending humans into space. Instead, the "search for territory," has become more important than the search for knowledge: "The search for territory is basic for animals and for mankind. Accessibility of space is a question of technology, and when the technology exists, it is used. So I say, let's go for having the territory. It's nothing more than that. That's what's motivating George W. Bush. And I don't want to be left out."
Before Bush brought up the subject, Europe's position was that it was more interested in a long-term, science-based mission to Mars than a return to the moon. Now ESA is shifting its thinking and trying to leverage the technology at hand into a manned vehicle that would also prove useful for a moon mission and, conveniently, fit on top of the Ariane 5 rocket. The key technology is already far along in development: the automated transport vehicle, a cargo ship being designed to replace Progress, Russia's archaic unmanned supply ship, as the main tool for ferrying water, food, and equipment to the space station. The Jules Verne is the first of six transport vehicles Europe expects to build. It is undergoing tests at the European Space Research and Technology Center in Noordwijk, a seaside resort town in the Netherlands, and its maiden voyage is expected to take place next year.
THE Jules Verne doesn't look like much—a squat, cylindrical ship resembling a bulky communications satellite. At its center is a cargo bin big enough to store more than seven tons of supplies, from oxygen and water to spare batteries and food. Despite its workaday role, the vehicle will be twice as large as anything ever launched on an Ariane rocket. And it will incorporate technology Europe has never had before.
Reacting in part to NASA's reluctance to share any hardware that might have military applications, ESA turned to Russia to purchase the docking mechanism, which allows the vehicle to hook up to the station. The Europeans were also drawn by Russia's work on autonomous docking. ESA engineers improved on the Russian design by adding a guidance system that allows the vehicle to dock without any human intervention at all. One of the biggest problems in docking is knowing the exact orientation of the ship relative to the station; if tab A is going to fit into slot B, the tab and the slot cannot be askew. The old Progress has an onboard radar system that can tell how far the ship is from the station and what its approach angle is, but it provides no information about the station's orientation. The Jules Verne has a more advanced system, built around a camera with image-recognition software that zeros in on the five reflective markers arranged in a pyramid shape on the space station. From the pattern of those reflectors, the Jules Verne's computers can figure out if it is approaching the station from the proper direction or if it needs to maneuver and try again.
Although the Jules Verne is far from being a manned space capsule, or "crew-transfer vehicle" in engineering terms, ESA officials are confident that they can and should transform it into one. "The automated transfer vehicle is for cargo, not astronauts, but it could be adapted," Sacotte says. "To be dependent on one technology—the space shuttle—is not safe." He says a European space capsule would not replace the space shuttle. But it could be useful to ferry crews to low Earth orbit or even to the moon. The ship's cargo hold is large enough to carry three astronauts easily, and it could transport as many as six people over short distances. Even in the current, cargo-only version, the hold is pressurized and insulated.
At a meeting of European ministers this month, Sacotte may propose expanding the automated transfer vehicle to carry crew. It is not clear, however, how the ministers will respond. There are no official estimates of how much the conversion will cost, but it will not be cheap. The potential consequences of safety problems on a manned ship are far greater than on an unmanned cargo
THE TEST CHAMBER
Photo by Ferit Kuyas
The 80,000-cubic-foot Large Space Simulator at the European Space Research and Technology Center is one of the world's most sophisticated spacecraft test chambers. It mimics the effects of vacuum as well as those of sunlight and radiation in space. The resulting data have helped the European Space Agency hone its recent successful robotic missions, including the Huygens lander on Titan and Mars Express.
ship. "We would have to think of any kind of malfunction," says Jean-François Clervoy, a former flight-test engineer and astronaut who works on the transfer-vehicle team, "and then figure that if it had any two at once, we must still be able to save the vehicle." The biggest safety limitation is that the Jules Verne has no reentry capability. It is designed simply to burn up. (A controlled landing seemed beside the point, since the vehicle will be filled to the brim with space-station garbage on the way back.) ESA could add a small reentry capsule onto the vehicle, but it would eat up space and limit the payload to three astronauts.
In their search for funds, ESA officials are talking about shaking loose money earmarked for the space station. They could justify that move because NASA, as part of its original obligation to its space station partners, was supposed to build an emergency escape vehicle to carry astronauts back to Earth. NASA came up with a concept called the X38—an escape pod with a lifting-body design, shaped like a fat wing, that was supposed to land using a steerable parachute—but it became clear that the design was too expensive. Director Sean O'Keefe killed it when he took the helm at NASA in 2001. ESA officials could propose participating with the Americans in the creation of a new escape vehicle to stand in for the canceled X38. NASA might then use a version of that vehicle to carry astronauts back to the moon.
If that gambit fails, or if ESA simply wants to hedge its bet, Europe might collaborate with Russia on the Clipper, a partially reusable vehicle that looks like a squatter, smaller space shuttle. Like Europe's proposed crew-transfer vehicle, the Clipper would sit atop a rocket (rather than strapped on like the space shuttle) and could carry astronauts to the International Space Station, the moon, and beyond. In principle it would replace both Russia's unmanned Progress capsule and the manned Soyuz—the one that caused André Kuipers such discomfort. At its December meeting, ESA is expected to request $60 million to begin development work on the Clipper. The final project would cost a total of $300 million, a pittance compared with the nearly $5 billion NASA spends annually on its shuttle program. Russian space officials say the Clipper could begin flights by 2011.
GETTING astronauts out of Earth orbit and onto the moon or Mars is only one element of a robust manned space program. For the much longer voyage to Mars, robotic craft are essential, both as scouts to find good landing sites and as cargo ships to ferry supplies and equipment. Europe has taken the lead in developing an innovative, extremely efficient propulsion technique for such unmanned missions.
The technology got a test run last year, when ESA's Smart-1 arrived at the moon and began snapping images of the surface. The launch of the lunar orbiter hardly made news in the United States. The event hardly made news in Europe either, probably because sending a small probe to a destination that the Apollo astronauts visited 35 years ago no longer seems like a big deal. But the significance of Smart-1 is how it got there.
Smart-1 set out conventionally, atop an Ariane 5 rocket launched from French Guiana. Once it reached its transfer orbit, peaking at 22,000 miles above Earth, the craft unfolded a small pair of solar panels, and its engine began producing a dim blue glow, gently lifting Smart-1 into higher and higher orbits around Earth. After 17 months of continuous acceleration, the probe reached an orbit so high that it overcame Earth's gravity and was captured by that of the moon. It then began peering with an infrared camera into lunar craters in search of signs of ice and measuring topography with radar and optical cameras. Meanwhile, the engines kept firing, sending Smart-1 into a set of ever-tighter orbits. One British tabloid's headline aptly declared, "Europe's First Lunar Voyage to Use Star Trek–Style Ion Power."
Much of the credit for Smart-1's success belongs to physicist Jose Antonio Gonzalez del Amo, who has spent the past 16 years developing ion propulsion at the Noordwijk laboratories. Gonzalez, a boyish man with a thick shock of unruly brown hair, picks up a version of the probe's engine to demonstrate the simplicity of the technology. It is nothing more than a flat, cylindrical chamber with a round metal grille on one side. The engine creates thrust by accelerating xenon ions—atoms stripped of one or more electrons, giving them a positive charge—through the negatively charged grid and spewing them out the back of the ship at 4,000 miles per hour.
Ion propulsion is a godsend for Europe's space program: cheap, reliable, and extremely efficient. Ion exhaust is much faster than the exhaust from a chemical rocket, so an ion engine can produce 10 times as much thrust from each pound of fuel. That drastically reduces the amount of propellant the ship needs to carry, the size of its fuel tanks, and its total weight. Smart-1's entire voyage required just 165 pounds of xenon gas and the electricity generated by the craft's 46-foot-wide span of solar panels.
The trade-off for efficiency is poor acceleration. Smart-1's engine generates a mere .07 newton of thrust, about the effort your hand has to exert to overcome the weight of a postcard. That is why Smart-1's voyage to the moon took 17 months. An ion-powered ship would need about five years to make a one-way trip to
Mars, compared with seven months for a ship powered by chemical rockets. The crew might travel to Mars by chemical thrust, and the cargo could be sent ahead of time by ion power. "I did the calculations years ago," Gonzalez says, pulling a notebook from his shelf. "With ion propulsion, you could afford to double the payload on a trip to Mars. Really, Mars is too close—you don't have time to get up enough speed. But ion propulsion would work well for Mercury and for the outer planets." NASA tried an ion engine once, on its experimental Deep Space 1 probe, but never followed up. The Europeans seem more committed to the technology: ESA's upcoming unmanned Mercury craft, BeppiColombo, will use ion engines too.
Gonzalez faces a challenge in upsizing ion propulsion so that it can work to supply human-scale missions to Mars. Getting an 11-ton cargo payload there in five years would require about 150 times as much thrust as sending Smart-1 to the moon. Supplying the necessary electricity would require a huge array of solar cells, roughly 10,000 square feet. A much tidier solution is a nuclear power source, which is far more compact and delivers a steady flow of electricity, regardless of its distance from the sun. At the mention of this possibility, however, Gonzalez's excitement drops, as though he had bitten into something sour. In Europe, the nuclear option is not acceptable. "It would be nice to have a nuclear reactor," says Gonzalez. "But we will have to make do without one."
EUROPE'S Aurora manned space program may have the giddy quality of a dream, but solving its twin challenges—building a vessel to carry a crew into deep space and designing the engines that can reach interesting destinations—pushes it toward mundane pocketbook realities. In its proposal to the ESA board, the Aurora planning commission weakly warned that "cost estimates are at this stage just guesses." The figure will most likely run into the tens of billions of euros, a huge stretch beyond Europe's modest space budget. Still, Aurora got a significant boost in July when Germany, which has the largest economy within the ESA, agreed to participate in the program.
Meanwhile, Europe is actively courting China, which sent its first astronaut, Yang Liwei, into space two years ago on a white-knuckle ride reminiscent of the first Mercury missions. Although China's technology is antiquated, the country is modernizing rapidly and can draw on breakneck economic growth to support plans for lunar colonies. "You'd be shocked to know how much money China is spending on its manned space program," says Manuel Valls Toimil, the head of program integration for ESA's manned missions. He is leading efforts to negotiate a partnership. The agency is also cultivating its ties with Russia and Japan and could act as an intermediary in combining the resources of the two nations—which, for historical reasons, refuse to collaborate directly with each other.
The real money in space travel is still with NASA, and its shuttle is still the only vehicle large enough to carry astronauts like André Kuipers into orbit in comfort. Michael McKay, head of ESA's advanced mission concepts and technologies office, argues that the most plausible way to get humans back to the moon and onto Mars is through international collaboration. But collaboration does not mean that ESA will accept a role as a junior partner. "We are very encouraged by NASA's declarations," McKay says, "but NASA has had difficulties meeting its commitments. This should be a partnership of equals, with respect on both sides." At least until ESA finds the means to travel on its own dime.
EUROPE'S STEPPING STONE TO MARS
The European Space Agency's Aurora program outlines a progression of missions to stretch the agency's capabilities. A preliminary timetable envisions a manned mission to the moon in 2024, an unmanned test spaceship to Mars in 2026, and a cargo ship there in 2030. European astronauts would finally set down on Mars in 2033. The plan assumes no major breakthroughs in materials or propulsion technologies.
>The vehicle that would take Europeans to Mars would be assembled in low Earth orbit over two to six years and would require 29 rocket launches lifting 1,700 tons of material and equipment. The current design concept has three building blocks:
>A propulsion module consisting of four stages, each with four Vulcain 2 rocket engines (now being readied for an upgrade of ESA's Ariane 5 rocket), to propel the spacecraft from low Earth orbit to Mars.
>A cylindrical transfer habitation module, 65 feet long and 20 feet in diameter, to house the crew on its journey to and from Mars. Facilities include crew quarters, exercise and work stations, a kitchen, a social gathering area, and the capsule for the reentry of Earth's atmosphere at the end of the mission. Four solar panels, 17 feet by 50 feet, provide electricity.
>A Mars excursion vehicle, 40 feet long and 20 feet wide, to provide transport to and from the planet. It has three parts. A descent module equipped with an inflatable heat shield, parachutes, and a propulsion system takes the astronauts and their hardware to the surface. A surface habitation module houses them while they are on the ground. A Mars ascent vehicle—a two-stage rocket and crew capsule—returns the astronauts to the transfer habitation module, which then breaks from Mars orbit and heads back to Earth.
>Launch is tentatively set for April 8, 2033, when Earth and Mars are closest together. New launch windows open every 26 months, but any delay means a longer trip to Mars, which increases the amount of fuel needed and exposes the crew to more radiation along the way. The spacecraft would carry six astronauts; three would land on the surface, while three would remain in orbit around Mars.
>The ideal mission timeline runs as follows: 200 days from Earth to Mars, 571 days in Mars orbit and on the surface, and 207 days from Mars back to Earth, for a total duration of just over 2 and a half years.
>Even with 3 and a half inches of shielding on the ship, male astronauts would be exposed to enough radiation to increase their risk of cancer by up to 20 percent; for women, the risk would be even higher. Exercise and therapeutic time in a centrifuge would help avoid the chronic bone loss that occurs in zero g.
>Once the astronauts are on Mars, their journeys outside the landing craft will be limited to six hours. They will always travel in pairs, leaving one person in the landing vehicle. Trips will be limited to about half a mile of walking from the landing vehicle or three miles of driving in a rover.
>ESA has not set a price tag on its Mars mission but recognizes the magnitude of the task. "Europe is determined to get to Mars, but we can't do it by ourselves. We need to go there as part of an international effort," says Piero Messina, head of external and institutional relations for the Aurora program. Interestingly, the final stages of ESA's timetable look very much like the equivalent plan taking shape within NASA. Barring the discovery of an ultra-low-cost energy source, a merger of the two programs will likely be necessary before any human sets foot on another planet. —Zach Zorich
The European Space Agency has posted a set of online resources about its Aurora program. See www.esa.int/SPECIALS/Aurora.
The ESA also offers access to its preliminary plans for a manned Mars mission. Go to ftp://ftp.estec.esa.nl/pub/aurora/Human_Missions_to_Mars.
Imagining Space: Achievements, Predictions, Possibilities, 1950–2050. Roger D. Launius and Howard E. McCurdy. Chronicle Books, 2001.
For current information about SMART-1, visit www.esa.int/SPECIALS/SMART-1.
NASA's next generation of ion propulsion is being developed by the Glenn Research Center: www.grc.nasa.gov/WWW/RT2002/5000/5430patterson.html.
The last 50 years of Russian and U.S. space exploration is examined in Space: A History of Space Exploration in Photographs, text by Andrew Chaikin, Firefly Books Limited, 2004.