They have a problem

By Charles Seife in Pasadena ITS missions have got faster and cheaper—but they don’t seem to be getting any better. After losing two spacecraft since September, NASA’s policy of exploring the Solar System on a shoestring is in disarray, and the critics are closing in. But many space analysts warn that the agency’s problems run much deeper than the loss of a few probes. In the post-Cold War world, they argue, NASA is in danger of losing its raison d’être. And by trying to reinvent itself as the torchbearer for the search for extraterrestrial life, the agency is building its future on shaky ground. “It’s not something you can hang a $13 billion-a-year agency on,” says John Pike, a space analyst with the Federation of American Scientists in Washington DC. When NASA administrator Dan Goldin made “faster, cheaper, better” his mantra in 1992, he had little choice. Billion-dollar probes such as Galileo, now finishing its mission to Jupiter and its moons, were soaking up so much of NASA’s funds that the agency could only launch one science mission every 18 months or so. And spending $1 billion on a mission is no guarantee of success. In 1993, NASA lost contact with the Mars Observer satellite, presumed to have been disabled by an explosion in a fuel line as the craft tried to slip into orbit around the Red Planet. At first, Goldin’s attempt to do more with less appeared to be paying off. The Mars Pathfinder mission, which landed on the Red Planet in July 1997, was a resounding success. And the Mars Global Surveyor, which entered orbit two months later, achieved many of the Mars Observer’s goals for a fifth of the cost. But even then, the warning signs were beginning to show. Mars Global Observer flirted with disaster when one of its solar panels was used for an “aerobraking” man oeuvre, exploiting the friction of the Martian upper atmosphere. The panel looked likely to break, forcing a rethink of the manoeuvre that saw the craft enter its mapping orbit a year behind schedule. This year, the problems have come thick and fast. The loss of the Mars Climate Orbiter and the Mars Polar Lander are just the highest profile disappointments. The Wide-Field Infrared Explorer, an orbiting observatory, was unable to fulfil its primary scientific mission after the hydrogen needed to cool its sensors leaked away into space in March. Two months earlier, the Near Earth Asteroid Rendezvous mission had failed to make its date with asteroid 433 Eros. And while the Deep Space 1 experimental probe did make its flyby of asteroid Braille in July, its camera was pointing the wrong way. There’s now a widespread feeling that the “faster, cheaper, better” policy means cutting corners, while mission controllers are being worked too hard without adequate training. Even NASA staff are speaking out. “If we had 10 per cent more in the integration and test phase, we could have done so much more,” sighs David Crisp, project scientist for NASA’s New Millennium space science program, reflecting on the Mars Polar Lander. “We were living on vapours.” Crisp thinks that Goldin will have to “tune up” the budgets for the cheapest missions, giving them a bit more money so that scientists don’t have to make fatal compromises to get them aloft. Boosting mission budgets by 10 or 20 per cent would seem to be an easy way to solve the problem. But that’s where Goldin’s real headaches begin. In the late 1960s, at the height of the Cold War space race, the Apollo programme alone received as much as 0.8 per cent of the US’s gross domestic product—equivalent to more than $60 billion today. But as the Soviet Union dissolved, so did Congress’s enthusiasm for space. NASA’s entire annual budget is now just $13 billion, and this year the agency only narrowly avoided losing a further $1 billion in 2000. Winning money from Congress depends on two things: showing that the spending will bring investment and jobs to the districts and states represented by influential members of Congress, or exciting the interest of ordinary voters. The lure of lucrative aerospace contracts has so far kept the International Space Station alive. And in 1996, NASA found a sexy new justification for space science: life. Nestled within an ancient chunk of Martian meteorite lay tiny structures that resembled fossilised bacteria. No longer was NASA confined to planetary physics and atmospheric science, neither of which are likely to set the public’s pulse racing. The science of “astrobiology” was born. Since then, NASA has increasingly played up the search for life when justifying its planetary missions. The failed Mars Polar Lander was designed to solve one the biggest mysteries in planetary science: why the surface of Earth’s sister planet is bone dry. The lander was armed with a robot arm to burrow into the soil, a laser to analyse the atmosphere and oodles of other high-tech gadgets to analyse the past and present Martian climate and help unravel the planet’s ancient history. Yet as exciting as this mission might be to planetary physicists, astrobiology seized the public relations agenda. Newsweek’s cover shouted about “The New Search for Life on Mars”. Likewise, when astronomers announced that they had found six new planets orbiting distant suns earlier this month, the real value of the discoveries lay in the possibility of understanding the mechanics of planet formation in ways that would have been impossible a mere five years ago. Yet when the researchers talked to the press, they stressed how five of the six planets spent most of their time in the “habitable zone” around their stars, where the temperature is just right to keep water in its liquid form. This public relations strategy may be understandable, but some scientists fear that it could backfire. The evidence for life in the Martian meteorite has since been dismissed by many experts, and even if there are signs of life somewhere on Mars, the chances of a craft like the Polar Lander finding it are slim. As for the possibility of extrasolar planets harbouring life, there’s simply no way at the moment that we can tell. The lure of alien life may secure funding for some high profile missions. After Mars, the icy ocean on the Jovian moon Europa is likely to be the next target. But a scientifically interesting mission to barren Pluto is already effectively dead. The danger is that by pinning its hopes on astrobiology, NASA is gambling with its future. The public could soon lose interest if the search for life fails to yield rapid results. Goldin denies that he is placing too much emphasis on biology, pointing put that it consumes a tiny portion of NASA’s budget. “Almost all NASA missions focus on chemistry and physics.” But he adds: “If NASA isn’t investing in biology, we’re not going to be able to do the things we want to do.” Nevertheless, some scientists feel NASA should make more of its undoubted strengths. Missions such as the Hubble Space Telescope, the Chandra X-ray Observatory and the Cosmic Background Explorer are all answering some of the fundamental questions in astrophysics, cosmology and planetary science: how did the Solar System form? What is the nature of matter in the cosmos? How will the Universe end? Whatever the answer, analysts such as John Logsdon of George Washington University in Washington DC think that NASA must start arguing a more coherent case now if it is to secure its future. “I think it’s in danger,
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