To core Cassini-Huygens scientists, the partnership between Darmstadt and Pasadena is nearly as thrilling as the lander’s experience on Titan’s surface will be—and, they fear, as ephemeral. “We thought we would open a new era of international planetary enterprise,” says Toby Owen, a University of Hawaii astronomer who in 1980, with French colleague Daniel Gautier, championed what would eventually become Cassini-Huygens. “But it didn’t happen, and it’s a little sad that it didn’t. Now America and Europe are each planning their own missions to Mercury. Why do we need two?”
Though necessary for ambitious space missions like Cassini-Huygens, international collaborations are now jeopardized by the U.S. security climate—in particular, stepped-up enforcement of the International Technology and Arms Restrictions, or ITAR, regulations. Even as the Internet makes sharing research much simpler technically, planetary scientists fear that paranoia will squelch future global space coordination. “The fact that I had to take my clothes off and be searched on a U.S. domestic flight because of my British accent creates an unpleasant impression,” says David Southwood, the Imperial College of London physicist who is ESA’s chief scientist. “But when we’re securing a box of electronics for NASA on board the International Space Station without being allowed to know what’s in it, that really makes the working climate difficult.”
ESA depends on NASA’s cooperation for its broader ambitions. European planetary craft would be helpless, for instance, without the U.S. Deep Space Network of communication radar antennas. But the ITAR regulations are discouraging. “Cooperation with NASA is more and more difficult,” says Jean-Pierre Lebreton. “They don’t want Europe working on any subsystems which they see as on a critical path.”
The Planetary Society’s Louis Friedman believes that Cassini-Huygens could probably not have been done without international cooperation, and he worries about the new U.S. policy of going it alone. “The recently announced lunar mission and Mars sample return are all being planned domestically without international involvement,” he says, “which I think is a huge mistake.”
Space exploration has always been an odd blend of millennial vision and civil-service bureaucracy, and Cassini-Huygens has seen extremes of both during its quarter-century gestation. The visionaries who got it started were inspired, in their various countries, by Voyager, which opened the outer solar system in the early 1980s and convinced space aficionados that unmanned missions could be as much of a rush as Apollo. “I remember investigators fighting for a seat at the terminals at JPL so they could look at Voyager images on closed circuit,” recalls the University of Arizona’s Jonathan Lunine. Titan, obviously reachable yet still unseen, struck this throng of scientific imaginations as a natural focus followup.
The idea of Europe going to Saturn, David Southwood recalls, was at the time “seen as laughable” to anyone outside the visionary circle and many within. ESA had been formed only seven years before—in 1973, when John Glenn was already a U.S. senator and Yuri Gagarin was long dead—and its mission, beyond building a rocket with a French name, was unclear. Then Daniel Gautier found a resourceful ally in Wing Ip, an astronomer who lobbied for a Titan probe while at Germany’s Max Planck Institute in the early 1980s and now works at Taiwan’s National Central University. When in 1982 ESA put out an all-points-bulletin for mission proposals, Ip set to work on a Titan plan. “ESA was very flexible just then,” Ip notes. “It was a chance that didn’t happen often and might not happen again.”
Not that Ip—who was born in Macau, earned his doctorate at the University of California at San Diego, and then followed his thesis adviser to Max Planck—immediately found common language with Gautier, a Parisian who in the Voyager period was working at NASA’s Goddard center. “Daniel, being French, thought he owned Titan and no one should interfere with his plans,” Ip remembers. “But eventually he agreed to talk to me.”
Upstart ESA was raising the level of its game elsewhere too. In 1985, it showed up NASA by sending the Giotto probe to Halley’s Comet, cooperating with the Soviets and Japanese, who also sent spacecraft. The United States alone sat out the mission to Halley.
Besides the independent streak in U.S. space policy, NASA’s bureaucratic customs differ from those of ESA, most markedly in budgetary practices. The 15 nations that kick in funds to Europe’s space agency make up their collective mind slowly. The Huygens team worked for five years before its first presentation to the ESA board, and final project approval came only in 1988. But once a project is okayed, funding is locked in until the mission is finished, and that rigidity proved a lifesaver for Cassini-Huygens during decades of shifts in the U.S. Congress’ moods. ESA’s firm resolution stayed Congress’ hand in 1993-’94, when budget hawks had Cassini in their sights, Toby Owen recalls. “When we were hanging by a thread, the director general of ESA wrote to Newt Gingrich telling him Europe wouldn’t support the International Space Station if the U.S. didn’t back Cassini,” Owen relates. “Without ESA, we wouldn’t be here.”
“Here,” for the little disk of hope and dreams called Huygens, is two billion miles away and approaching Saturn, its computers to be awakened for one final diagnostic before Christmas, when it cuts its Cassini umbilical cord and hurtles into black space. For space veterans like Toby Owen and Daniel Gautier, “here” tends to be a restless orbit around the globe, anywhere there are ideas to be shared and plans to be laid for the next grand scheme—a lander for Jovian moons Europa and Ganymede, a Titan orbiter accompanied by balloons that could float and photograph just above the surface. Requests for interviews for this story found Huygens scientists perpetually somewhere else—the Arizonans in Grenoble or London, the Parisians at Goddard and JPL.