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EAVESDROPPING ON OLYMPUS—LET THE GAMES BEGIN
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- SPINNING BRAINS
- DOUBLE WHAMMY: ASTEROIDS DELIVERED ONE-TWO PUNCH
- ANALYSIS: BUSH STANDS BY HIS SPACE PLAN
- SPACE SCIENCE PIONEER VAN ALLEN QUESTIONS HUMAN SPACEFLIGHT
- CHINA TO LAUNCH SECOND MANNED SPACE MISSION IN 2005
- THE SPILLPROOF EARTH—ELECTRONS TO PASS THE "WHITE GLOVE" OVER A SPACEPROBE
EAVESDROPPING ON OLYMPUS—LET THE GAMES BEGIN From Astrobiology Magazine 22 July 2004 As the world prepares for the 2004 Olympics in Athens, one can ask the question: "Are we on Earth the only ones who will watch the games?" Recall that a key story point in the Carl Sagan novel, Contact, relies on the unique premise that we are not the only onlookers. Sagan's scenario depends on the 1936 Olympic Games in Berlin as symbolically transmitting our existence beyond the solar system. Earth inhabitants showed their interest in contests for national pride and athletic skills to a listening audience on the nearby star Vega. In the novel and screenplay based on the book, our own message in a bottle then boomerangs back to us, as a greeting from another world that they have heard us. The plot device that the Earth leaks intelligent signals has appeared in many science fiction stories of first contact. Broadcasting early radio shows or even reruns of I Love Lucy to another culture on the home world, much less another planet, has long been a source of potential bemusement. How would such a randomly selected reflection of our culture be interpreted?  
Left: the first TV transmission from Earth, the 1936 Berlin games, and now the farthest strong signal from an electromagnetically-leaking planet. Because of the Second World War these were to be the last Olympics until 1948. Right: Arecibo, the world's largest dish, radio telescope (in Puerto Rico). Perhaps Sagan chose to single out first transmission as the 1936 Berlin Games because the content is so antithetical to what we might have hoped for. Or in an ideal case, a warlike contest of brawn and nationalism seems less than what one might have planned as a friendly greeting. What as a species could show us as less prepared for greeting another civilization than the way we greet each other? After all the '36 Games advertised the politics of a nationalistic Germany, on the precipice of the bloodiest war in human history, when virtually no part of our globe could remain untouched by battle and conflict. Even the notion of competitive games or a contest to rank national and individual power, while oftentimes used historically to trigger truces or peace talks, also represents a metaphor for unabashed cultural ambitions and seemingly arbitrary or artificial borders that simply disappear when viewed from space. In that context, what maturity can humans portray to species even more unlike ourselves, not just athletically but intellectually, culturally or morally? As David Grinspoon noted on this dilemma in his book, Lonely Planets: The Natural Philosophy of Alien Life, an advanced civilization observing happenings on Earth might easily reply to our first signal: "Humans of the planet Earth, you want to encounter other beings? First you have to learn to live with your different people?" Was this challenge encapsulated by the 1936 Berlin Olympics? From his years in designing SETI strategies, University of Washington Professor, Woody Sullivan thinks what Hollywood did with Carl Sagan's book, Contact, particularly the first half, is about as close as a popular film can get to what it's like to do real SETI research. Much of the opening sequence owes a debt to Sullivan, since he spearheaded the scientific understanding that the Earth is leaking electromagnetic signals all the time, mainly from TV and some military radars. Twenty-five years ago, "most SETI was set up mainly to look at beacons from another civilization. But we don't have a devoted beacon broadcasting from Earth even. A priori, we don't know that a civilization would set up a beacon. But we Earthlings are leaking all the time, just from our daily activities." Just as the film, Contact, begins, the viewer is taken on a voyage, as if riding such a signal from the depths of the universe until it zooms back towards Earth. Before Sullivan's work, previous SETI strategists more often thought of broadcast sources from another civilization as likely to be directed beacons, or singularly devoted transmitters. Instead Sullivan supposed a viewpoint about the more constant background noise, one that unavoidably might date back to the film's key plot-point when the advanced civilization finds the first terrestrial TV broadcast—the carrier signal when Adolf Hitler hauntingly introduced the 1936 Olympic Games in Berlin. "These are not great examples of our civilization," said Sullivan. "I call this eavesdropping," continues Sullivan. "Sometimes when you eavesdrop, you get a better idea of what is really going on, say at a party. So when another civilization is eavesdropping on us, they may actually get a better idea about what is going on with Earth. There is more to Earth, as a planet, than what we could send on the gold record that traveled on the Voyager spacecraft. We, as a planet, are not just about listening to Chuck Berry." It is, according to Sullivan, easy to miss whether TV coverage of the Olympics can serve as an effective SETI message. Particularly when the picture itself, the moving color image, is the least of what an advanced civilization might want to watch, the physics of TV is more important than the actual content carried. Sullivan notes "the input is not actual TV programs in the broadcast signal. But I was talking first about the video carrier, which is a single frequency carrier. Your TV locks onto it. You can't get the whole program information. From another planet, you could get a lot or dozens of those carriers, about a rotating planet with Doppler shifts. That communicates a lot of information to a receiver." Whether the 1936 or 2004 Olympics represents a global signal that we leak apparently has less to do with the event itself and more to do with the electromagnetic spectrum. Sullivan considers "what signals we Earthlings are optimally leaking to our neighbors... should be broadly spread, strong, and possibly discernable as an intelligent signal... So for a good signal for reception, you want to balance a trade-off between both powerful and broad-area beaming." Sitting down to watch the Olympics from 10 to 100 light-years away may not reveal much of interest about a race of carbon-based bipeds. We will leak the 2004 Games to travel into deep space, just like we did with the 1936 Games. Most of what qualifies as signals of sufficient persistence and strength have a small probability of reaching just the right antenna. But chances are better that another civilization will not be caught watching our TV. Sullivan concludes TV is only one way we declare ourselves outside our solar system: "Military radar, called the Ballistic Military Early Warning System or BMEWS, is a very powerful broadcast, but carries no real information. There are a couple other strong radars on the planet. The strongest radar is Arecibo, but it covers a very tiny bit of sky. The odds that you were in that patch, or broadcast path, is unlikely." Whatever the source of our leaked signals, there is a timeliness to considering how we decorate our own local solar neighborhood. As the SETI Institute's Jill Tarter, often cited as the inspiration for the lead scientist in the movie, Contact, describes: "When you realize that you live in the first generation of humans with access to a technology that might answer the age-old question, 'Are we alone?' all other scientific questions fade in importance." Read the original article at http://www.astrobio.net/news/article1093.html. SPINNING BRAINS By Patrick L. Barry and Tony Phillips From NASA Science News 23 July 2004 One day, astronauts might travel through the solar system onboard spinning spaceships. Can human brains adapt? Next time you go to a playground, try this. Bring along a ball and a friend, and get on the merry-go-round. Try throwing the ball to your friend across the ride from you, or even just a few feet beside you, and see if they can catch it on the first attempt. They won't be able to, guaranteed. In fact, your throw will be way off. You'll feel your arm pulled strangely to one side as you make the throw, and once in flight, the ball will veer wildly. Physicists call this the "Coriolis effect," and it happens on any spinning platform. Hurricanes swirl because of the Coriolis effect, the spinning platform being Earth itself. Contrary to popular belief, Coriolis forces do not control your bathroom drains—Earth doesn't spin that fast. But playing ball on a merry-go-round is definitely a Coriolis experience. Space travel could be a Coriolis experience, too. Researchers have long known that spinning spaceships like a merry-go-round could solve a lot of problems. In weightlessness, astronaut's bones and muscles weaken. It's tricky to eat and drink, and even use the bathroom. Inside a spinning spaceship, on the other hand, there would be an artificial gravity (due to centrifugal forces) that keeps bodies strong and makes everyday living easier.  An artist's concept of a spinning spaceship. Image credit: John Frassanito & Associates, Inc.
The problem is, spinning spaceships also come with a strong Coriolis effect. Tossed objects veer. Reach out to touch a button ... and your finger lands in the wrong spot. Could astronauts adapt to this? And if so, could they adapt well enough to perform dependably in the life-threatening environment of space? That's what researchers James Lackner and Paul DiZio are trying to figure out. With support from NASA's Office of Biological and Physical Research, these two scientists are performing a series of experiments with people in rotating chambers to learn how well astronauts might adjust to life onboard spinning spaceships. They also hope to find training techniques that could help ease the transition from non-spinning to spinning, and back again. 
A rotating room used by Lackner and DiZio in their experiments at the Ashton Graybiel Spatial Orientation Laboratory, Brandeis University. "Experiments done in the 1960s seemed to show that people did not adapt well to rotation," says Lackner, the Meshulam and Judith Riklis Professor of Physiology at Brandeis University in Waltham, Massachusetts. "But in those experiments, the subjects didn't have well-defined goals for their movements. We've found that when a specific goal is given for the motion, people adapt rather quickly." Given specific motion goals (such as reaching out to touch a target), people in their study learned to move accurately after only 10 to 20 attempts. Such a rapid adjustment surprised the researchers. Says DiZio, an associate professor of psychology at Brandeis, "we speculate that when a goal is present, the brain dictates the desired motion to the muscles more precisely. Deviations from that motion are detected more readily by sensory feedback to the brain." Why should people have this natural ability to adapt to rotation? Our bodies and brains might have evolved, to a degree, to deal with the Coriolis effect. Every time you turn and reach for something simultaneously, you have a brief Coriolis experience: turning atop an office chair; playing basketball; spinning to see what made that strange noise behind you! In each case, your brain makes on-the-fly Coriolis adjustments. Other discoveries surprised the researchers, too. For example, after rotating for a while, people in their study no longer perceived the Coriolis effect. The veering pull on their arms and legs seemed to vanish. Their brains had compensated for it, so their minds no longer took notice of it. Even stranger, when test-subjects first return to a non-rotating environment, they report feeling a Coriolis-pull in the opposite direction. It's just a trick of the mind, notes DiZio. After another 10 to 20 attempts at a goal-oriented motion, their brains readjust to the non-rotating world, and the phantom effect goes away. DiZio and Lackner have found that people can adapt to rotational speeds as fast as a carnival-ride-like 25 rpm. That's about as fast as people turn their bodies during day-to-day life. For comparison, a spinning spaceship would likely rotate more slowly, perhaps 10 rpm, depending on the size and design of the craft. To exert more control over the conditions of their experiment, the researchers have tried something innovative: simulating the Coriolis effect with a robotic arm. Seated subjects would try to make certain motions with their arm while the robotic arm gently pulls on their wrist in a way that mimics the Coriolis effect. The advantage of this approach is that the robotic arm can be reprogrammed to pull in a variety of ways, thus testing how subjects respond to different conditions. Using the arm, DiZio and Lackner have discovered that people can adapt to a small, variable force even when it's masked by a larger, constant force. So, for example, astronauts should be able to adapt to a variable Coriolis effect in spite of some constant background force, such as the steady push of a spacecraft's ion-propulsion thrusters. Many questions remain un-answered. Do results based on arm motions apply to the whole body? Does carrying heavy tools make a difference? After adapting once, can a person re-adapt more easily later? What's the best way to train astronauts for life in a rotating home? Lackner and DiZio plan to tackle these questions and more as their research continues in the months to come. Read the original article at http://science.nasa.gov/headlines/y2004/23jul_spin.htm. DOUBLE WHAMMY: ASTEROIDS DELIVERED ONE-TWO PUNCH By Robert Roy Britt From Space.com
By Frank Sietzen From UPI and SpaceDaily
By Leonard David From Space.com
From Agence France-Press and SpaceDaily 27 July 2004 China is expected to launch its second manned spacecraft, Shenzhou VI, on a five-day mission in the second half of next year, state media quoted a Chinese space expert as saying Tuesday. Huang Chunping, chief of the China Manned Space Program's rocket carrier system, added China would realize its dream of space walk with the launch of Shenzhou VII, although he did not specify a date, Xinhua news agency reported. Read the full article at http://www.spacedaily.com/2004/040727185643.og7higl6.html. THE SPILLPROOF EARTH—ELECTRONS TO PASS THE "WHITE GLOVE" OVER A SPACEPROBE From Astrobiology Magazine 27 July 2004 Texas A&M nuclear researchers are working with the NASA Jet Propulsion Laboratory to examine how electron beam technology can sterilize spacecraft components. Dr. Suresh Pillai, director of the National Center for Electron Beam Food Research, and Dr. Lee Braby, a research professor in the department of nuclear engineering, received a grant from NASA to investigate how electron-beam irradiation can contribute to keeping future spacecrafts from seeding other planets and moons inadvertently. "Deep space missions must be properly sterilized to distinguish between organisms brought from Earth and those that may be indigenous to other planetary bodies, such as Mars," Pillai said in a Texas A&M report. This concern culminated in the wording of the 1967 Outer Space Treaty, which said that nations should pursue studies of solar system bodies "so as to avoid their harmful contamination and also adverse changes in the environment of the Earth." "Electron-beam irradiation is potentially a better solution than dry-heat sterilization, the key NASA-approved technique," said Pillai. When this method of sterilization is used, electrons are accelerated between two charged anodes and cathodes until they are sufficiently fast to damage the biology of whatever microbes might be tyring to hitch-hike an unwanted extraterrestrial voyage. The technique is already widely used in the plastics and food preservation industries. 
A thin section of Strain 121, the so-called "unboilable bug" which survives high-pressure autoclave heating to a record breaking 121 degrees Celsius, or about 250 degrees Fahrenheit. "Growth at 121 C is remarkable," reported discoverers of Strain 121, Lovley and Kashefi, "because sterilization at 121°C, typically in pressurized autoclaves to maintain water in a liquid state, is a standard procedure, shown to kill all previously described microorganisms and heat-resistant spores." (The white bar equals one micron.) Image credit: Derek Lovley, U. Mass., Amherst. NASA's Planetary Protection Program aims to preserve pristine conditions both going outwards and when returning future samples to Earth. John Rummel of the Office of Planetary Protection and Michael Meyer of NASA's Astrobiology Program wrote that Earth is surprisingly hard to wipe off what otherwise might appear to retain its pristine mint conditions. "On Earth," noted Meyer and Rummel, "living organisms are distributed throughout our planet: in rock at depths of over 1,000 meters (about 3,000 feet), in soil frozen for more than 3 million years, in 110-degree Celsius (230-degree Fahrenheit) seawater and so on. Life can reach high abundances in the right environments (a human body contains about 50 percent nonhuman cells, by number, and sheds about 50,000 living cells per day). It is impossible, under normal conditions, to visit Earth and not encounter life." By a similar token, outgoing spacecraft have to be wiped clean using a combination of heat, low-humidity and gamma irradiation in those cases where the electronics are suited for such exposures. Pillai said dry-heat sterilization involves heating components at 110°C for at least 40 hours. Unlike dry heat, electron beams sterilize at relatively lower temperatures and involve radiation-damage to microbial DNA for the techniques success at preserving spacecraft cleanliness. "Unfortunately, many components are heat sensitive and undergo deterioration making them incompatible with heat sterilization," Pillai said. The research will revolve around heat-sensitive materials such as low-temperature adhesives, polymers used in making lander balloons and printed circuit board materials. The focus will be on developing electron-beam technology for spacecraft materials and components. "The proposed work will advance electron-beam sterilization technology to an operational level," Pillai said. "This will be a major advance towards adding a new and highly capable sterilization technique to the current limited NASA planetary protection tool set." NASA's instruction on planetary protection expresses this careful approach to protecting from cross contamination: "The conduct of scientific investigations of possible extraterrestrial life forms, precursors, and remnants must not be jeopardized. In addition, the Earth must be protected from the potential hazard posed by extraterrestrial matter carried by a spacecraft returning from another planet. Therefore, for certain space-mission/target-planet combinations, controls on organic and biological contamination carried by spacecraft shall be imposed in accordance with directives implementing this policy." Requirements for forward decontamination vary from Category I, for missions to bodies of no biological interest (for example, the Sun), to Category IV, where a spacecraft will land on a planet of potential biological interest. Category V is reserved for missions that visit another solar system body (other than the Moon) and return to Earth. Directory: projects -> marsbugs -> 2004 projects -> Rajinder Sachar Committee projects -> Cape Lookout National Seashore Historic Resource Study By projects -> Cape Lookout National Seashore Historic Resource Study By projects -> Revolutionizing Climate Modeling – Project Athena: a multi-Institutional, International Collaboration projects -> What is a Hurricane? projects -> General Information projects -> Press Information projects -> 1 Introduction 3 2 Designing an Embedded System 4 2004 -> Editor/Publisher 2004 -> Editor/Publisher Download 1.87 Mb. Share with your friends:
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