Should Dying Patients Get Unproved Drugs? (page 92) Saving Nature That SCIENTIFIC -WORKS FOR pagePEOPLE50 AMERICAN October 2007 $4.99 www.SciAm .co m SPECIAL REPORT The Future of " A Preview of the Orion Spaceship " 5 Essential,Things to Do Up There Consciousness Scientists Debate How Neurons Make Us Aware Diamond Chips Sparkling Processors Spin Quantum Logic Diagnosis to Go New Portable Microlabs ESSENTIAL THINGS TO DO IN SPACE Planetary scientists have articulated goals for exploring the solar system TO A CHILD OF THE SPACE AGE, system, from Mercury to Pluto. But budget cuts, books about the solar system from cost overruns and inconsistency of purpose before 1957 are vaguely horrifying . have cast long shadows over NASA. At the very How little people knew. They had least the agency is going through its most unset- no idea of the great volcanoes and tled period of transition since Nixon shot down canyons of Mars, which make the Apollo moon missions 35 years ago. Mount Everest look like a worn hill- "NASA continues to wrestle with its own iden- ock and the Grand Canyon like a road- tity," says AnthonyJanetos of the Pacific North- side ditch. They speculated that Venus west National Laboratory, a member of a Na- beneath its clouds was a lush, misty jungle, or tional Research Council (NRC) panel that scru- maybe a dry, barren desert, or a seltzer water tinized NASA's Earth observation program. "Is ocean, or a giant tar pit-almost everything, it it about exploring space? Is it about human ex- seems, but what it really is: an epic volcanic ploration, is it about science, is it about explor- wasteland, the scene of a Noah's flood in molten ing the outer universe, is it about exploring the rock. Pictures of Saturn were just sad: two fuzzy solar system, is it about the space shuttle and rings where today we see hundreds ofthousands station, is it about understanding this planet?" of fine ringlets . The giant planet's moons were In principle, the upheaval should be a happy gnats, rather than gnarled landscapes of meth- occasion. Not only are robotic probes flying ane lakes and dusty geysers. hither and yon, the human space program is no All in all, the planets seemed like pretty small longer drifting like a spent rocket booster. Pres- places back then, little more than smudges of ident George W. Bush set out a clear and com- light. At the same time, Earth seemed a lot larg- pelling goal in 2004-namely, to plant boots in er than it does now. No one had ever seen our lunar and Martian soil. Though controversial, planet as a planet: a blue marble on black velvet, the vision gave NASA something to shoot for. coated with a fragile veneer ofwater and air. No The trouble is that it quickly turned into an un- one knew that the moon was born in an impact funded mandate, forcing the agency to breach or that the dinosaurs died in one. No one fully the "firewall" that had traditionally (if imper- appreciated that humanity was becoming a geo- fectly) shielded the science and human space- logic force in its own right, capable ofchanging flight programs from each other's cost overruns. the environment on a global scale. Whatever "I presume it is not news to you that NASA else the Space Age has done, it has enriched our doesn't have enough money to do all the things view of the natural world and given us a per- it's being asked to do," says Bill Claybaugh, di- spective that we now take for granted. rector of NASA's Studies and Analysis Division . Since Sputnik, planetary exploration has Cash doesn't exactly flow like liquid hydrogen gone through several waxing and waning phas- at space agencies in other countries, either . es. The 1980s, for instance, might as well have NRC panels periodically take a step back and been the dark side of the moon. The present ask whether the world's planetary exploration looks brighter : dozens of probes from the world's programs are on track. The list ofgoals that fol- space programs have fanned out across the solar lows synthesizes their priorities. www .SciAm .co m SCIENTIFIC AMERICAN 69 onito arth's lit Amid all the excitement of buggying around Mars and peeling back the veil ofTitan, people sometimes take the mundane yet urgent task of looking after our own planet for granted. NASA and the National Oceanic and Atmospheric Administration (NOAA) have really let it slide. In 2005 Janetos's NRC panel argued that the "sys- tem of environmental satellites is at risk of col- lapse." The situation then deteriorated further. NASA shifted $600 million over five years from Earth science to the shuttle and space station. Meanwhile the construction of the next-genera- tion National Polar-Orbiting Operational Envi- ronmental Satellite System ran seriously over budget and had to be downsized, stripping out instruments crucial to assessing global warming, such as those that measure incoming solar radia- " TWIN SATELLITES of the Gravity ment discovers that the sun is brighter than its tion and outgoing infrared radiation. Recovery and Climate Experiment predecessor found, is it because the sun really Consequently, the two dozen satellites of the (GRACE), which detect the brightened or because one of the instruments Earth Observation System are reaching the end of gravitational distortions caused was improperly calibrated? Unless satellites over- by the movement of water, are their expected lifetimes before their replacements lap in time, scientists may not be able to tell the already past their original are ready. Scientists and engineers think they difference . The venerable Landsat series, which planned lifetime. can keep the satellites going, but there is a limit. has monitored the surface since 1972, has been "We could hold out, but we need a plan now," on the fritz for years, and the U.S. Department " LANOSAT 7 IMAGE, taken at says Robert Cahalan, head of the Climate and ofAgriculture has already had to buy data from multiple wavelengths, shows Radiation Branch at the NASA Goddard Space fires in Alaska and the Yukon in Indian satellites to monitor crop productivity. For Flight Center. "You can't wait till it breaks." 2004. A failure in 2003 hobbled some types of data, no other nation can fill in. If a satellite dies before relief arrives, gaps the satellite, and the entire The NRC panel called for restoring the lost open up in the data record, making it difficult to program has been on budgetary funding, which would pay for 17 new missions establish trends. For instance, if a newer instru- drip-feed for more than a decade. over the coming decade, such as ones to keep tabs on ice sheets and carbon dioxide levels-es- sential for predicting climate change and its ef- fects. The root issue, though, is that climate ob- servations fall somewhere in between routine weather monitoring (NAAA's specialty) and cut- ting-edge science (NASA's) . "There's a fundamen- tal problem that no one is charged with climate monitoring," says climatologist Drew Shindell of the NASA Goddard Institute for Space Studies. He and others have suggested that the U.S. gov- ernment's scattered climate programs be consol- idated in a dedicated agency, which would own the problem and give it the focus it deserves. " Fund the 17 new satellites proposed by the National Research Council over the next decade (estimated cost: $500 million a year) 7O SCIENTIFIC AMERICAN October 2007 Prepare an Asteroid Defense Like climate monitoring, guarding the planet from asteroids always seems to fall between the cracks . Neither NASA nor the European Space Agency (ESA) has a mandate to stave off human extinction. The closest they come is NASA's Space- guard Survey, a $4-million-a-year telescope observing program to scan near-Earth space for kilometer-size bodies, the range that can cause global as opposed to merely regional destruction. But no one has done a systematic search for region destroyers, an estimated 20,000 ofwhich come within striking range of our planet . No Office of Big Space Rocks is standing by to eval- uate threats and pick up the red phone if need be. It would take 15 years or longer to mount a A NOT A SIGHT YOU WANT TO SEE : An asteroid of the dinosaur-killing sort would reach from sea level to the cruising altitude of commercial airliners . defense against an incoming body, assuming that the technology were ready to go, which it isn't. To plug these holes, the NASA team also con- "Right now the U.S . doesn't have a comprehen- sidered building a $500-million infrared space siveplan," says aerospace engineer Larry Lemke telescope and putting it in its own orbit around ofthe NASA Ames Research Center. THREATENING the sun. It could pick up essentially every threat This past March, at Congress's request, NASA ASTEROIDS to Earth and, by studying bodies at multiple published a report that could serve as the start- Dinosaur killers, 10 kilometers across, wavelengths, pin down their mass to within 20 ing point for such a plan. By its analysis, search- hit every 100 million years on aver- percent. "If you wantto do it right, you want to ing for 100- to 1,000-meter bodies could large- age . Globally devastating asteroids, go to the infrared in space," says planetary sci- one kilometer or larger, come every ly piggyback on the Large Synoptic Survey Tele- entist Donald Yeomans of the Jet Propulsion half a million years or so .
Details
-
File Typepdf
-
Upload Time-
-
Content LanguagesEnglish
-
Upload UserAnonymous/Not logged-in
-
File Pages8 Page
-
File Size-