MARSBUGS: The Electronic Astrobiology Newsletter Volume 9, Number 27, 29 July 2002. Editor/Publisher: Dr. David J. Thomas, Science Division, Lyon College, Batesville, AR 72503-2317, USA. dthomas@lyon.edu Contributing Editor: Dr. Julian A. Hiscox, School of Animal and Microbial Sciences, University of Reading, Reading, RG6 6AJ, United Kingdom. J.A.Hiscox@reading.ac.uk Marsbugs is published on a weekly to monthly basis as warranted by the number of articles and announcements. Copyright of this compilation exists with the editors, except for specific articles, in which instance copyright exists with the author/authors. While we cannot copyright our mailing list, our readers would appreciate it if others would not send unsolicited e-mail using the Marsbugs mailing list. The editors do not condone "spamming" of our subscribers. Persons who have information that may be of interest to subscribers of Marsbugs should send that information to the editors. E-mail subscriptions are free, and may be obtained by contacting either of the editors. Information concerning the scope of this newsletter, subscription formats and availability of back-issues is available from the Marsbugs web page at http://welcome.to/marsbugs or http://www.lyon.edu/webdata/users/dthomas/marsbugs/marsbugs.html. _____________________________________________________________________ CONTENTS 1) STEALTH DEEP-WATER CAMERA SYSTEM MAY FIND NEW DEEP-SEA CREATURES Harbor Branch Oceanographic Institution release 2) DUST IN "EARTH'S ATTIC" COULD HOLD EVIDENCE OF PLANET'S EARLIEST LIFE By Vince Stricherz 3) OBSERVING "ALIEN" LIFE ON EARTH By Tariq Malik 4) LIFETIME OF COMPLEX LIFE: GREAT DEBATES PART IV From Astrobiology Magazine 5) FIRST EVIDENCE FOR EARLY METEORITE BOMBARDMENT OF EARTH University of Queensland release 6) IS E.T.'S WORLD A PLANET? By Seth Shostak 7) SAILING TO MARS By Julian Hiscox 8) CAVEAT IMPACTOR--AN ASTEROID WITH ALMOST NO CHANCE OF HITTING EARTH MADE BIG HEADLINES THIS WEEK By Tony Phillips 9) ASTEROID 2002 NT7: POTENTIAL EARTH IMPACT IN 2019 RULED OUT By Don Yeomans 10) RELENTLESS EVOLUTION: GREAT DEBATES PART V From Astrobiology Magazine 11) BOOK REVIEW: COSMIC DRAGONS (LIFE AND DEATH ON OUR PLANET) By Julian Hiscox 12) BOOK REVIEW: EARTH, LIFE AND THE UNIVERSE... EXPLORING OUR COSMIC ANCESTRY By Julian Hiscox 13) BOOK REVIEW: X15--THE NASA MISSION REPORTS By Julian Hiscox 14) NEW ADDITIONS TO THE ASTROBIOLOGY INDEX By David J. Thomas 15) CASSINI SIGNIFICANT EVENTS NASA/JPL release 16) CONTOUR STATUS REPORT NASA/JHUAPL release 17) CONTOUR CHANGING ITS ATTITUDE NASA/JHUAPL release 18) INTERNATIONAL SPACE STATION SCIENCE OPERATIONS STATUS REPORT NASA/MSFC release 19) MARS ODYSSEY THEMIS IMAGES NASA/JPL/ASU release 20) STARDUST STATUS REPORT NASA/JPL release _____________________________________________________________________ STEALTH DEEP-WATER CAMERA SYSTEM MAY FIND NEW DEEP-SEA CREATURES Harbor Branch Oceanographic Institution release 18 July 2002 A Harbor Branch Oceanographic Institution scientist will soon combine stealth and ingenuity with a deep-sea self-contained underwater camera of her own design in a quest to capture images of creatures that live in the darkest depths of the world's oceans. You might say Dr. Edie Widder, a world-renowned expert in marine bioluminescence, is literally taking a scientific "shot in the dark" that may result in images of creatures that have never been seen before. The "Eye In The Sea" camera system Dr. Widder designed will be used for the first time on July 23 in the deep Monterey Canyon area off Monterey Bay, California, at depths of between 700 meters and 1,000 meters. What makes the camera so unique is its ability to sit alone on its tripod on the deep ocean bottom, waiting quietly for a flash of bioluminescence to bring it to life. The instant any creature in the inky depths flashes its chemical signal, the camera will record the bioluminescent flash, and then send out a beam of red light, invisible to the animal, while simultaneously taking a digital image. Dr. Widder explains why she hopes to capture images of creatures that may have remained undiscovered until now. For one thing, only a tiny percentage of the ocean depths have been explored and scientists believe there could be creatures living in those depths that humans have never seen. The second reason is simple--stealth. "A big noisy submersible with its bright lights can be seen or heard or otherwise sensed by deep-sea creatures from a long way away, and that has no doubt scared away a lot of animals," Dr. Widder said. Dr. Widder has been trying since 1994 to make her "Eye in the Sea" project a reality. She finally succeeded in launching the effort last year with a $35,000 check from Harbor Branch Oceanographic Institution to the Harvey Mudd College of Engineering for initial development. The National Oceanic and Atmospheric Administration (NOAA) provided $15,000 to help develop the deep-sea housing that has to protect the camera system from the crushing pressure at depth, and Dr. Widder has financed the rest of the project from her own Harbor Branch budget and from the sale of video and still images. Monterey Bay Aquarium Research Institute (MBARI) is providing ship and ROV (remotely operated vehicle) time as well as an extra set of the special batteries required by the system. Dr. Widder plans to deploy "Eye in the Sea" for the first time on July 23rd, and the system will be retrieved and any images it has taken will be downloaded the next day. It will then be dropped right back into the ocean depths for another 24 hours, and retrieved for the second time July 25th. Dr. Widder plans to deploy the camera for longer periods of time in other parts of the ocean after the system and any images it takes are evaluated. For more information, or to arrange for interviews or to request images, please contact Geoff Oldfather, Harbor Branch Director of Public Relations, at 561-465-2400 x206, or on his cell phone at 561- 216-1458. You can learn more about Dr. Widder and marine bioluminescence at www.biolum.org and to view an animated sequence of the "Eye in the Sea" system, please visit www.at-sea.org in August for "Fathoming the Gulf Stream--Natures Pharmacy and Eyes in the Sea"--Harbor Branch's online mission coverage which will include daily dispatches from our team aboard the R/V Seward Johnson, science and technology articles, video streams, animations, and more. Harbor Branch Oceanographic Institution is one of the world's leading nonprofit oceanographic research organizations dedicated to exploration of the earth's oceans, estuaries and coastal regions for the benefit of mankind. An additional article on this subject is available at http://www.spacedaily.com/news/life-02zk.html. _____________________________________________________________________ DUST IN "EARTH'S ATTIC" COULD HOLD EVIDENCE OF PLANET'S EARLIEST LIFE By Vince Stricherz University of Washington release 22 July 2002 The dust has been piling up in Earth's attic for billions of years, and now some scientists want to sift through the accumulation to see if they can find evidence of the planet's earliest life. "It is up there. I don't know how common it is, but somewhere up there is at least one fist-sized chunk of rock with Earth's name on it," said John Armstrong, a University of Washington doctoral student in astronomy and astrobiology. "It would probably take hundreds of years of human habitation to find it and recognize it, but it's there." "Up there" is the moon, what Armstrong and his colleagues refer to as Earth's attic. And while he doesn't expect to actually find a large chunk of Earth rock, he believes there is likely a wealth of planetary debris in the form of fine particles on the moon's surface. In an upcoming edition of Icarus, an international journal of solar system science, Armstrong and colleagues Llyd Wells, a UW graduate student in oceanography, and Guillermo Gonzalez, an assistant physics and astronomy professor at Iowa State University, argue that humans should seriously consider returning to lunar exploration. Any mission, they say, should include a search for fossils of some of Earth's earliest microbial life. In its very early history, 3.8 billion to 3.9 billion years ago, comets and asteroids constantly bombarded the Earth. Some of those bodies hit with such force that chunks of the planet's surface were ejected beyond the pull of its gravity. The three astrobiologists believe some of that ejected material went directly to the lunar surface, while other material went into orbit and some gradually fell to the moon. Finding rocks, or even particles, from that period could be invaluable in understanding how life on Earth came to be as it is today, since any fossils found likely would be from a time long before life on Earth developed great complexity and diversity. Because of the moon's position in the inner solar system, in theory it has collected material from all the planets. Earth matter probably is most abundant, since it is closest to the moon, but Armstrong, Wells and Gonzalez expect that fallout from Mars and Venus also is abundant enough that it could be recovered. They have calculated that, on average, perhaps 22 tons of Earth material is spread over every 38 square miles of the moon. If they are right, Armstrong said, that means about 10 parts per million of lunar material originated on Earth. However, it would not necessarily be identifiable as Earth material. And while material blasted directly to the moon probably came down on the side facing Earth, any material that ended up in orbit could have been deposited anywhere on the lunar surface. "One thing we're still debating is where would be the best place to look," Armstrong said. The scientists believe Earth material from that long ago probably became buried over time, so one strategy they have devised is to look for recent craters in which old rocks have been excavated. They also are searching through lunar samples already returned to Earth, on the off chance those samples might contain rocks that originated on the planet. They would be able to tell by isotope ratios or by determining whether materials in the rocks were formed in water-- something that cannot occur on the moon. At the very least, Armstrong hopes to find dust from pulverized Earth rocks, material that can be dated and can give clues about the history of bombardment by asteroids and meteors and how that affected evolution. If materials are more intact, they might contain interesting elements that would shed light on the early Earth's environment and how life existed at that time. Less likely, he said, would be the discovery of rare, volatile elements that would tell about the early atmosphere. The least likely find--and the one most prized--would be microbiological fossils from 3.9 billion years ago. "The part I like about this is that it makes the moon a window on the early Earth," Armstrong said. "It also would give us access to samples you can't get anywhere else at the moment." Currently there are no plans for a U.S. mission to the moon, though other nations are considering the possibility. It has been 30 years since the National Aeronautics and Space Administration's last manned mission, and three years since the controlled crash of the robotic Lunar Prospector spacecraft in a search for water on the moon. Armstrong believes a new lunar mission would benefit science on several levels and could help prepare and test systems for eventual martian exploration. To search for material of Earth origin, he suggests the inclusion of a rover that could systematically pass over a specific area, conduct tests and prepare samples to be launched back to Earth. The only way to find the Earth rocks, he said, is to find a way to look specifically for them. "If you find one of these things, it's going to be hard to convince someone that it's of Earth origin," he said. "But if you find more than one, then you can begin to classify them as a group of materials and begin to make a more convincing case." Contacts: Vince Stricherz Office of News and Information University of Washington Seattle, Washington Phone: 206-543-2580 E-mail: vinces@u.washington.edu John Armstrong Phone: 206-543-9039 E-mail: jca@astro.washington.edu Llyd Wells Phone: 206-543-0147 E-mail: chimera1@ocean.washington.edu Guillermo Gonzalez Phone: 515-294-5630 E-mail: gonzog@iastate.edu [http://www.washington.edu/newsroom/news/images/lunar.jpg] The moon as seen from the Stardust spacecraft during a flyby of Earth in 2001. Image credit: NASA/JPL. An additional article on this subject is available at http://www.space.com/scienceastronomy/moon_earth_020723.html. _____________________________________________________________________ OBSERVING "ALIEN" LIFE ON EARTH By Tariq Malik From Space.com 24 July 2002 The best place to learn how to identify extra-terrestrial organisms may not be in space, but beneath the Earth's oceans. Scientific expeditions to deep volcanic vents along the mid-Atlantic Ocean floor could serve as a primer to the types of microorganisms that could lurk beneath the surface of the Jovian moon Europa--long thought to harbor its own ocean beneath an icy crust. The Arlington, VA-based company, Space Adventures, has begun offering trips to such vents near the Azores island chain in a joint effort with the Russian research vessel Akademik Keldysh. The Akademik holds a pair of submersibles capable of reaching depths of 20,000 feet (6,090 meters) to make the dives. "It's no doubt that the things we're going to learn here are applicable for the search for microbial life on other planets," said recent diver and former astronaut Owen Garriot, an alumnus of NASA's Skylab and Space Shuttle missions. "The people at NASA are very interested in looking for life on the other planets of the Solar System." Get the full story at http://www.space.com/scienceastronomy/planetearth/vents_europa_020724 .html. _____________________________________________________________________ LIFETIME OF COMPLEX LIFE: GREAT DEBATES PART IV From Astrobiology Magazine 24 July 2002 Today's debate asks whether life on Earth is doomed to extinction due to the changing nature of the sun. If the Earth's habitable zone does have a time limit, does the same necessarily hold true for other worlds? The participants in today's debate are: Debate moderator Michael Meyer, the Senior Scientist for astrobiology at NASA Headquarters and Program Scientist for the Mars 2001 Odyssey Mission. Donald Brownlee, co-author of Rare Earth, and Professor of Astronomy of the University of Washington in Seattle. Frank Drake, Chairman of the Board of Trustees of the SETI Institute, and Professor of Astronomy and Astrophysics at the University of California at Santa Cruz. David Grinspoon, Principal Scientist in the Department of Space Studies, Southwest Research Institute in Boulder, Colorado, and author of the forthcoming book, Lonely Planets: The Natural Philosophy of Alien Life. Christopher McKay, planetary scientist with the Space Science Division of NASA Ames Research Center. Peter Ward, co-author of Rare Earth, and Professor of Geological Sciences at the University of Washington in Seattle. Michael Meyer: As our sun grows ever brighter, the Earth's habitability will be reduced. How long can life last on Earth? Do you think all life in the universe shares a similar fate? Peter Ward: Our sun has about another 7 billion years before it enters the red giant phase. Surely, then, we could expect a long period of habitability. But the reality is that it takes more than the correct amount of solar energy to make a planet habitable. This is especially true for complex organisms such as animals, which have a very narrow range of temperatures and nutrient requirements compared to microbes. The presence of complex life on the Earth will end in no more than a billion years (and perhaps much sooner), due to a sequentially predictable breakdown of habitable systems on our planet. The systems in question are those that serve to regulate the Earth's temperature and atmospheric carbon dioxide content. New models suggest that over the next billion years, we can expect atmospheric carbon dioxide to drop to levels that can no longer support photosynthesis. This will be followed by a temperature rise on the planet to above 50 degrees Celsius. Both of these factors will spell the end of complex life on Earth. When the global temperature rises to about 70°C, the oceans will be lost to space, and this might spell the end of all life on Earth. David Grinspoon: Above a certain level of solar input, an oceanic planet must lose its water. This is a robust conclusion of fairly simple physics, so unless the sun is a very weird star it will keep heating up and, unless someone intervenes, Earth will lose its oceans. Long before that the carbon dioxide needed by plant life will be drawn down into the rocks in a futile attempt by Earth's natural thermostat to maintain homeostasis. Clouds can help, by reflecting sunlight back to space, but can only delay the inevitable. If you don't believe me, just ask Venus. The specific details and timing of how this heat death will come about are much less certain, as they depend on climate modeling. Climate modeling for our own atmosphere is an imprecise art (if you don't believe me just read the newspapers), and becomes more uncertain when we apply it to the atmospheres of far-future Earth, or other planets. So, there is a lot of slop in these dates. Peter Ward: The period of time that one can expect complex life to exist will vary from world to world. Our "Rare Earth" hypothesis is that on most planets, this will be too short a time to allow complexity to arise at all. Perhaps the fates of Earth and the other planets in our solar system are not typical at all. But still it is certain that all planets as abodes for life age through time, and as they change they eventually lose the ability to sustain life. Sometimes they do so over immense periods of time, sometimes it might be fast. Some die of old age and some are killed off by cosmic catastrophe. But all end eventually. This salient fact must be considered in any reflection about the frequency of life in the cosmos. For our own star, the flaring into a red giant will be followed by a stellar retreat into a dwarf stage that will last untold billions of years. As astronomers gaze out into the heavens with their powerful telescopes, they see billions of such stellar tombstones. The galaxy is littered with dead stars, the markers of how many dead planets, and of how many dead civilizations that for a time circled these stars when they were young and vigorous? The presence of these stellar graveyards are thought-provoking reminders that any estimate about the frequency of life in the universe must take into account the fact that once evolved, life has a finite life span on any world. And, like the varieties of ages of individuals, the life span of life-covered planets depends in large part on a whole slew of characteristics. David Grinspoon: If complex life sometimes leads to sentient life with powers slightly greater than our own at present, then it need not accept "natural" climate evolution as inevitable. Right now we are in the stage of inadvertently altering our global climate, but it is not inconceivable that we, or someone else, could advance to the stage of purposefully altering climate for the benefit of the biosphere. If that happens, then reports of the death of the habitable zone are greatly exaggerated. We should at least ponder the possibility that sentient life, once it arises, will not let its planet become uninhabitable quite so easily. Assume for a second that humans, or our sentient descendants, do not wipe themselves out any time soon, and solve the problems of asteroid impacts and other threats to long term survival. How hard would it be, with the technology of even 100 years from now, to say nothing of 10,000 or several million years from now, to put up a sunshade and keep the Earth cool from our warming star? Or move to Mars for a while? Once complex life gets just slightly more advanced than we are now, then it becomes quite possible that sentient creatures can alter the habitability of worlds and planetary systems. Christopher McKay: Based on our own experience, we know that civilization and technology radically change the rules. Even extrapolating 1,000 years into the future (a brief instant on the scale of the age of the planet) we can imagine the transforming effect of intelligence on the distribution of life in our own solar system and possibly even our region of the galaxy. Frank Drake: Once a species has developed high technology, there are many strategies for dealing with the changing brightness of the home star. It has even been suggested by Gregory Benford that the main sequence lifetime of stars can be greatly extended by developing a technology which stirs the star, bringing fresh hydrogen to the core- -after all, about 90% of a star's mass is intact when the giant stage is approached. A far out idea to be sure, but it reminds us that clever technologies may be as yet unrecognized by us. The luminosity of the sun-like stars changes very gradually, over millions of years. This is enough time to mount a massive technological program to move outwards in the planetary system. Perhaps to terraform Mars, or the satellites of Jupiter; perhaps to utilize material from asteroids to build a constellation of space colonies. There is plenty of time, and the motivation will be there. As the sun collapses from the super giant phase, the creatures can move inward, eventually to huddle close to the white dwarf sun. There they will finally be at peace with the cosmos, with a supporting star whose lifetime will be many billions of years. Donald Brownlee: There is a common belief that life will always find a way and that the universe itself is bio-friendly. An extension of this line of thinking is that life will usually solve its problems, travel the universe, and perhaps even evolve to something far beyond our "wet life" based on cells, genetic codes, and complex chemical processes. On Earth, life so far has indeed "found the way" and after 4 billion years it has evolved to what we now consider to be normal. But was Earth lucky to get this far? Will its diverse biological communities be able to survive long into the future? Unless the universe actually is bio-friendly, our planet will have barely reached its present state before the ever-warming sun begins to degrade Earth's ability to support plants and vegetarians. Like it or not, this is probably nature's way. Even on the best of planets, advanced life only flourishes for a relatively short period of time. If advanced life only rarely evolves and doesn't last long when it does, it will be rare in the universe at large. The only way that I see that animals are likely to be common in the universe is if interstellar travel actually is so easy that the Noahs and Johnny Appleseeds of the cosmos just spread things around. I personally doubt that this happens. I believe that it is most likely that organisms as complex as animals only occur in transient cosmic oases widely separated by space and time. Planets form, they may develop life, but eventually the planet and its life perish. This cycle repeats endlessly in the cosmos. Likewise, civilizations form, they may send SETI transmissions or even launch time capsules, but they will never make direct physical contact. Additional information on this article is available at http://www.astrobio.net/news/article240.html. _____________________________________________________________________ FIRST EVIDENCE FOR EARLY METEORITE BOMBARDMENT OF EARTH University of Queensland release 25 July 2002 University of Queensland researchers have for the first time discovered terrestrial evidence of a meteorite bombardment nearly 4 billion years ago. It is widely accepted that the moon was heavily bombarded at this time, creating huge craters and basins. But although the effect of these impacts is still clearly visible on the moon today, movement of Earth's dynamic plates over geological time has reshaped the terrestrial surface dramatically, leaving little evidence of these catastrophic events. In a paper published in the international journal Nature, UQ researchers report evidence of the oldest impact events so far discovered on Earth. The research team of Dr. Ronny Schoenberg, Dr. Balz Kamber and Professor Ken Collerson of UQ's new Advanced Centre for Isotope Research Excellence (ACQUIRE) made the discovery by analyzing 3.8 billion year old rocks from West Greenland collected by Oxford University collaborator Professor Stephen Moorbath and from Northern Labrador in Canada collected by Professor Collerson. The researchers found these very old metamorphosed sedimentary rocks- -derived from the Earth's early crust--contain anomalies in the isotope composition of the element tungsten. "Such anomalies are usually found in meteorites. To our knowledge, this is the first time these anomalies have been shown to exist in terrestrial samples" Professor Collerson said. "There is no plausible mechanism by which tungsten isotope anomalies could have been preserved in the Earth's dynamic crust-mantle environment. Therefore, we conclude these rocks must contain a compound derived from meteorites." "We have in effect found a chemical fingerprint in the Earth's oldest terrestrial rocks of a heavy meteorite bombardment 3.8 to 4 billion years ago," he said. "This finding has implications for the origin of life on Earth as these giant impacts would have annihilated any possible existing life forms but also delivered complex molecules from carbonaceous chondrites--a type of meteorite--to the earth's surface," Dr.. Kamber added. "Further research on this unique collection of rocks will yield insight into the evolution of life on Earth provided provision of adequate research funding," Professor Collerson said. Contacts: Professor Collerson Phone: 07 3365 8505 E-mail: k.collerson@mailbox.uq.edu.au Dr. Kamber Phone: 07 3365 8580 Peter McCutcheon at UQ Communications Phone: 07 3365 1088 Additional articles on this subject are available at: http://www.space.com/scienceastronomy/planetearth/earth_bombarded_020 724.html http://www.spacedaily.com/news/deepimpact-02m.html _____________________________________________________________________ IS E.T.'S WORLD A PLANET? By Seth Shostak From Space.com 25 July 2002 Freeman Dyson is betting that alien life doesn't live on a world like yours. More specifically, if you check out the tentative wager this celebrated physicist has logged at the web site www.longbets.org, you'll see that Dyson's hunch is that the first discovery of extraterrestrial life will be made someplace other than on a planet or on a satellite of a planet. In other words, if we succeed in finding some biology beyond Earth, it won't be camped out on a large ball of rock. I have great admiration for Freeman Dyson's breathtaking ideas. But I suspect he's taking a long shot here. He hasn't qualified the bet to say "intelligent extraterrestrial life." So if an upcoming mission to Mars, Titan, or Europa discovers microbes busy eking out a living deep underground or afloat in hidden oceans of water or natural gas, then Dyson will have to pay up, assuming we haven't found some other biology first. Get the full story at http://www.space.com/searchforlife/dyson_seti_020725.html. _____________________________________________________________________ SAILING TO MARS By Julian Hiscox 25 July 2002 One of the current mission scenarios to Mars that is in vogue at the moment is based on the "Mars Direct" direct template [originally conceived by Robert Zubrin], which offers significant savings and benefits for the short term aim of getting humans to Mars before 2019, and includes some dual function hardware. Part of the idea is to generate the rocket fuel for the return journey to Earth on Mars using carbon dioxide from the atmosphere and hydrogen that has been brought from the Earth. However, the strategy still retains a large measure of the "use-once- only-and-throwaway" habits. These were at first an essential part of the early years of the development of space technology. However one alternative that should be considered for future martian exploration and transport of materials to Mars orbit is solar sailing. How do solar sails propel a spacecraft? In essence the idea is disarmingly simple, it is to make use of a small part of the vast flood of energy released by the nuclear reactions within the Sun and which radiates away into space, in the form of electromagnetic radiation, in all directions. Solar radiation is made up of a stream of photons, each of which carries momentum, and which exert a small but measurable pressure on any surface they hit. If the surface on which they impinge is a perfect mirror the pressure generated on that reflector is the maximum attainable for a given intensity of incident radiation. The radiation pressure generated is quite small. For a mirror directly facing the Sun it is proportional to the intensity of the incident radiation and inversely proportional to the square of the distance from the Sun. Because the pressure exerted by light is small the mirror that makes up a solar sail has to have a very large surface area and be of very low mass if it is successfully to propel a spacecraft. These requirements call for the use of the thinnest possible 'sailcloth' no thicker than 2.0 microns and perhaps as much as an order of magnitude thinner for high performance space sails. What are the advantages of using solar sailing craft for the exploration of Mars? The principal factors are economic. These include the elimination of propellant cost for flight between Earth/Mars and Mars/Earth. Complete reusability and long operating life of space sailing ships allows their capital cost to be amortised over a period of years or decades--that is over many flights. The virtual elimination of non-reusable hardware components also reduces greatly general operating costs. Together these and other factors contribute to a high capacity, low capital and low operating costs, space transportation system. Aerobreaking entry in to the martian atmosphere for a sailing ship delivered module would require only a small mass of onboard propellant. Fuel for the return to Mars orbit could manufactured on Mars, either in the same manner, but on a smaller scale, as proposed in the "Mars Direct" scenario, of from the electrolysis of martian water. For the long term exploration of Mars, perhaps leading eventually to the permanent settlement of the planet space, sailing ships win hands-down by offering potential operating cost reductions of approximately 80%. _____________________________________________________________________ CAVEAT IMPACTOR--AN ASTEROID WITH ALMOST NO CHANCE OF HITTING EARTH MADE BIG HEADLINES THIS WEEK By Tony Phillips From NASA Science News 26 July 2002 I slid a dollar bill across the counter, and the cashier handed back a lottery ticket. The odds for winning: 1-in-250,000. A long shot, but you never know. Walking out of the store, ticket in hand, I glance at a newspaper. "Tony Phillips wins the lottery!" the headline declared. Gosh, I thought, that seems premature... not to mention weird. Indeed, it's fiction. For one thing, I never buy lottery tickets. But mainly, no one would write such a headline based on such slender odds. Yet that's what happened this week, in real life, to an asteroid. On July 9, 2002, MIT astronomers discovered 2002 NT7, a 2 km-wide space rock in a curious orbit. Unlike most asteroids, which circle the Sun in the plane of the planets, 2002 NT7 follows a path that is tilted 42 degrees. It spends most of its time far above or below the rest of the solar system. Every 2.29 years, however, the asteroid plunges through the inner solar system not far from Earth's orbit. After a week of follow-up observations, researchers did some calculations. There was a chance, they concluded, that 2002 NT7 might hit our planet on February 1, 2019. The odds of impact: 1-in- 250,000. "Space Rock 'on Collision Course'," a headline declared days later. "Asteroid Could Wipe Out a Continent in 2019," another one warned. Really. "In fact," says Don Yeomans, the manager of NASA's Near-Earth Object Program at JPL, "the threat is minimal. One-in-250,000 is a very small number." The odds are not only low, but also uncertain. Yeomans explains: "We've been tracking 2002 NT7 for a very short time--only 17 days so far," Meanwhile, the asteroid takes 2.29 years to orbit the Sun. Predictions based on such a small fraction of an orbit are seldom trustworthy. It's becoming a familiar routine. Astronomers discover a near-Earth asteroid. With only meager data at hand, they can't rule out a collision in the distant future. Headlines trumpet the danger. Finally, the alarm subsides when more data lead to a better orbit-- one that rules out an impact. "As far as the public is concerned," says Jon Giorgini of JPL's Solar System Dynamics Group, "it just isn't worth getting worked up about an object with a couple weeks of data showing a possible Earth encounter many years from now. Additional measurements will shrink the uncertainty by a large amount--and Earth will (almost certainly) fall out of the risk zone." Already this is happening for 2002 NT7. The calculated probability of a collision with Earth is shrinking as astronomers add new data each day. "I suspect it will take only a few more weeks (or maybe months) to completely rule out an impact in 2019," says Yeomans. Giorgini explains further: "When we calculate an asteroid's position (based on measurements made at a telescope), the result isn't a single point in space. Instead, it's a volume of space where the asteroid could be with some probability. We deal with probabilities, not absolute answers, because the measurements contain errors." For example, optical data can be corrupted by twinkling and refraction in Earth's atmosphere. (Radar is better, notes Giorgini, but no radar data have yet been obtained for 2002 NT7.) "When you project this initial probability region years into the future, it naturally expands. For a newly discovered object with only a few days tracking, the uncertainty region can easily grow to cover a big part of the inner solar system. Because Earth is in the inner solar system, and can potentially cut through this volume of smeared out probability, we end up with finite impact probabilities." "A finite probability, however, is not really a prediction of impact," he cautions, "but a statement that one is possible." Of course, many things are possible. Like the newspaper headline "Tony Phillips wins the Lottery!" But most of them do not happen. JPL lists asteroids like 2002 NT7 on their Internet "risk page" not to raise an alarm, says Yeomans, but to alert astronomers when new discoveries merit attention. "It's important that we continue tracking these asteroids to refine their orbits," he says--the more observers, the better. What's an ordinary person to do? The next time you see a headline "Killer asteroid threatens Earth!" ask yourself two questions. Have we known about this space rock for more than a week or so? (If not, check again in a month. It probably won't be considered a killer then.) And what are the odds of impact? If you're more likely to win the lottery, there's probably nothing to worry about. Additional information on this article is available at http://science.nasa.gov/headlines/y2002/26jul_nt7.htm?list52260. Additional articles on this subject are available at: http://www.cnn.com/2002/TECH/space/07/24/asteroid.encounter.ap/index. html http://spacedaily.com/news/020725120601.mgn9y1gk.html _____________________________________________________________________ ASTEROID 2002 NT7: POTENTIAL EARTH IMPACT IN 2019 RULED OUT By Don Yeomans NASA/JPL release 28 July 2002 With the processing of a few more observations through July 28, we can now rule out any Earth impact possibilities for February 1, 2019. While we cannot yet completely rule out an impact possibility on February 1, 2060, it seems very likely that this possibility will be soon ruled out as well as additional positional observations are processed. Because the SENTRY system tracks a multitude of test particles in an effort to map the uncertainties of the asteroid's future positions, some of these test particles can take slightly different dynamical paths. Hence there are currently two entries for 2060 in our IMPACT RISK table. The entry with the higher risk (larger Palermo Technical Scale) would be the value that would then take precedence. _____________________________________________________________________ RELENTLESS EVOLUTION: GREAT DEBATES PART V From Astrobiology Magazine 29 July 2002 Otherwise known as Fermi's Paradox: if there is intelligent life out there, why haven't we found them yet? Where are they? The final part of our debate asks why we haven't found complex intelligent life, if indeed it does exist elsewhere in the universe. A thread of this debate also picks up on a comment made by Donald Brownlee (Debate IV)--that interstellar space travel may be impossible. Debate moderator, Michael Meyer, the Senior Scientist for astrobiology at NASA Headquarters and Program Scientist for the Mars 2001 Odyssey Mission. Frank Drake, Chairman of the Board of Trustees of the SETI Institute, and Professor of Astronomy and Astrophysics at the University of California at Santa Cruz. Christopher McKay, planetary scientist with the Space Science Division of NASA Ames Research Center. Donald Brownlee, co-author of Rare Earth, and Professor of Astronomy of the University of Washington in Seattle. David Grinspoon, Principal Scientist in the Department of Space Studies, Southwest Research Institute in Boulder, Colorado, and author of the forthcoming book, Lonely Planets: The Natural Philosophy of Alien Life. Michael Meyer: If there is intelligent life out there, why haven't we found them yet? Chris McKay: This is Fermi's paradox. Where are they? Or phrased differently: why aren't signs of galactic-scale intelligent life obvious in our telescopes? The simplest explanation for this is that we are the only, or at least the first, intelligent species in the galaxy. Can anyone give a good argument for why our type of civilization would not be obvious over much of the galaxy after a million years? David Grinspoon: If civilizations like ours were all over the galaxy, it would not be obvious. We are only listening, not broadcasting. We are not doing astroengineering. True, we are leaking sitcoms and beer commercials, but these are not easily detectable over most of the galaxy and certainly would not be interpreted as signs of true intelligence. So, in order to have an obvious presence, "our type of civilization" must become something quite different. Perhaps this is very rare or difficult. However, being a constitutional optimist, and considering the unimaginably vast reaches of time and space, I tend to think that sentient, long-lived civilizations should be out there somewhere. So, where are they? The reasoning behind Chris's (and Fermi's) question implicitly assumes certain things about the behavior of advanced civilizations. It assumes they will keep expanding their populations and increasing the size of their civil engineering projects. Looking at the history of our civilization and extrapolating to our future, I understand why you could draw such a conclusion. But it may be that truly sentient societies realize there is no future in unlimited expansion. We cannot keep expanding our population at our current rate. Even if we were somehow able to move out into space at the speed of light and colonize all available planets, we would still run out of space and resources and experience mass starvation within a thousand years. True minds will realize that such expansion is a dead end. Of course, the problem with this kind of explanation for "the great silence" (Fermi's paradox) is that it must apply to every single civilization out there. It is hard to believe that every society that ever forms will transform themselves into sustainably living, granola munching, navel staring, contemplative Buddhists before creating some observable signs of their presence. So, we must search for another answer. Frank Drake: A parallel question to this is: how long will the Earth's technology be detectable? A few decades ago we thought the visibility would last a long time--ever more powerful TV stations and radar installations were being built, and these are the strongest signs of our existence. But there is only so much bandwidth in the useful electromagnetic spectrum. To transmit ever-increasing amounts of information, portions of the spectrum must be shared. This is only possible if signal strengths are reduced so that transmissions on the same frequency do not interfere with one another. The textbook example of this paradigm is the cellular phone system. This signal reduction means we are well on our way to becoming invisible. So if the transmission of a rich cornucopia of information is what advanced civilizations do, they may become invisible. This is a rather counter-intuitive result, but a real one. This means that the detectable lifetimes of civilizations may be shorter than we have estimated, and hoped, alas. David Grinspoon: Another possibility is that they may not want us to know they are there. It's hard for us to fathom the possible motivations and behaviors of societies millions of years older than ours. It seems reasonable, however, to suppose that the differences between their capabilities and ours will be so great that it will be up to them, not us, how and when some kind of detection or contact is made. It is possible that they have decided it should be against the law to let us know they are there (The "Zoo Hypothesis" or the "Prime Directive"). This might be because they are protecting us, studying us, protecting themselves from us or what we might someday become, or waiting until the time is right to initiate us into the Galactic Club. The simplest explanation--that we are the only, or the at least first, intelligent species in the galaxy--requires an extreme violation of the Copernican Principle (which says the Earth is typical and common). This is especially true when you consider the generations of stars--with possible habitable planets--that lived for billions of years before our star and planet were even a twinkle in the eye in our parent molecular cloud. There has been so much time for someone to come along and achieve intelligence. Why should our present time be so special? It comes down to which unjustified pillar of scientific reasoning you prefer to violate: Occam's Razor (things are simple) or the Copernican Principle (our place is not special). Take your pick. Frank Drake: Every discussion of alien intelligence assumes that they will come visit us. But the expense and danger of space travel are formidable. A strong reason why such enterprises are not carried out may be that radio communication works so much better, is far cheaper, and you get your answers at the speed of light. Any reasonable transport of creatures across space calls for travel speeds that are a substantial fraction of the speed of light, otherwise it takes too long to go even to the nearest stars. But this exposes the spacecraft to serious hazards. Probably the most serious is the potential for collision with debris--and we are learning that space is full of debris. At relativistic speeds, even a collision with a particle of a few grams results in something close in energy to a nuclear bomb blast. Not good news for the space travelers. Also the energy requirements are ridiculous, at least to us. To send a spacecraft the size of a small airliner at one-tenth the speed of light requires as much energy as the U.S. now produces in more than a hundred years. And that just gets you someplace--it doesn't provide for a landing or a return home. To put it another way, it takes 10 million times as much energy to move a small space colony to another star as it takes to establish the same colony in the home system. And there is plenty of room at home. It is easily calculated that the energy of the sun is enough to sustain more than ten thousand billion billion humans. That seems like enough. Why go to the great expense and danger of going to other stars? Truly intelligent life would laugh at the idea. The only ones who might try are the dumb ones, and they don't know how. David Grinspoon: I agree that, given the time and energy constraints, any intelligent creatures would have to be nuts to attempt interstellar travel. But you would also have to be nuts to attempt to cross the ocean in a rowboat, and people have done that. Why do we need to go one-tenth the speed of light? What's the hurry? So what if travel times are thousands of years? From the perspective of an individual human life at this stage in our evolution, this seems like a long time. But will the galaxy never, ever, anywhere, produce a creature or cultural entity that doesn't find this span of time daunting? Even at these slow speeds, if someone decided to start spreading across the galaxy they would be able to spread across the whole Milky Way in a few hundred million years, tops, which is still short compared to the life of the galaxy. I also agree that radio communication makes much more sense than any form of interstellar travel for almost any purpose. Except [that] it's still more fun to go to the game than watch it on TV. I doubt we'll ever achieve warp drive or anything that makes interstellar travel so much faster, better, and cheaper that we can visit a new star system with shapely natives every week like Captain Kirk. Still, isn't it extreme to declare that no one will ever travel the interstellar distances? Donald Brownlee: I have always loved space travel in science fiction, but I take a very dim view of the likelihood that we will be able to send people more than just a short distance away. I know that a future without interstellar travel is a minority view, but it is not at all clear that technology could be developed to transport living humans to habitable places beyond our solar system. I think that it is odd that so many people are sure that we will inevitably evolve to a Star Trek society, able to zip across the Galaxy like we drive to the next state. Beaming up and all that stuff seems so easy on TV. Our best bet with foreseeable technology is to use antimatter fuel, but even if we could build the hardware it would take all of our planet's energy production for over a century just to make the fuel. Besides, there are additional problems in technology, funding, and human organization. New discoveries involving navigation and maneuvering are required to get to other earthly oases in space on a comfortable and timely basis. Can all the UFOers really be wrong? Time will surely tell. David Grinspoon: As many brilliant thinkers have pointed out, if a civilization survives to a certain point they could easily become immortal. That is, if they learn how to avoid asteroids and other natural disasters, tame any self-destructive instincts and learn to live sustainably, their lifetime effectively becomes the lifetime of the universe. Yes, I know there are nasty things like gamma ray bursts and other hazards we haven't even discovered yet, but we are talking about technology and an understanding of nature, and of self- understanding, that are many millions of years beyond our own. Migrating between stars to stay alive will not be a hurdle for these "old ones." Comparing this idea to Star Trek or UFOs is a cheap shot that ignores the serious literature on this topic. If you don't insist on making the trip within the current human life span, there are no huge technical hurdles. Donald Brownlee: I am sorry that David considered my previous comments about Star Trek and UFOs to be a cheap shot, but I really do believe that the difficulty of practical interstellar travel is horrendously underestimated. In my opinion, the public is being bilked by wishful thinkers that like to write books and muse about futures that we would like to believe are our logical destinies. Perhaps I take too much of a hard-nosed and practical view of this, but doing even simple things in space is difficult, unforgiving, and exceedingly expensive. I am aware of the studies of anti-matter rockets, beamed energy, interstellar ram jets, etc., but all of these ideas have severe problems. As I see it, known physics will never deposit living people on Earth-like planets around other stars. Doing so would require "warp speed" and/or harnessing exotic phenomena such as wormholes or zero-point energy. Unless such radical developments occur, mundane ideas such as anti-matter rockets will not do the job. We have gone to the moon, we can go to Mars, but that is likely to be the limit that our resources and foreseeable technology will allow. At our current rate of progress, humans may not even make it beyond the International Space Station. Our bounds in space may be as limited as they are on Earth. We have covered the Earth but it seems highly unlikely that we will ever live more than a kilometer above or a few kilometers beneath its surface. The suggestion that organisms could easily become immortal if they live long enough is intriguing. There are a number of issues here, including whether "immortal" means "relatively immortal" or "actually immortal." Forever is a very long time--I suggest that nothing physical can ever be immortal. Infinite time is something that the universe cannot keep up with unless things like child universes pop up from time to time to refresh the landscape. If things aren't miraculously refreshed, the universe just runs down over long time scales. According to new information, the expansion of the universe has accelerated. Lawrence Krauss of Case Western University says that an accelerating universe "would be the worst possible universe, both for the quality and quantity of life. All our knowledge, civilization, and culture are destined to be forgotten. There's no long-term future." A most bleak forecast and at the totally opposite end of the spectrum from predictions of immortal beings. David Grinspoon: I define "immortal" as lasting for the rest of the life of the universe, which may not be "really immortal" but may have to do. If we accept the idea that some civilizations can solve the problems which threaten their survival, attain peace, stability, control their populations, learn to intelligently engineer their solar systems, etc., then "immortality" happens. By definition it is an irreversible transition, so the immortals must slowly be accumulating. None of us know, but my sense is that the universe is bio-friendly. I doubt there are any other planets with a peculiar history and biosphere closely resembling Earth's, but I predict many, many inhabited worlds, and a large number with intelligence far in advance of anything we can even conceive of. Don't you love predictions like this? It cannot be proven wrong! Additional information on this article is available at http://www.astrobio.net/news/article242.html. _____________________________________________________________________ BOOK REVIEW: COSMIC DRAGONS (LIFE AND DEATH ON OUR PLANET) By Julian Hiscox 29 July 2002 Title: Cosmic Dragons (Life and Death on Our Planet) Author: Chandra Wickramasinghe Publication Date: 2001 Publisher: Souvenir Press ISBN: 0-285-63606-5 This is yet another laughable load of old nonsense from the pen of Professor Wickramasinghe, who judging by the references, must be living in his own scientific universe. The tenant of the book is that life has been transported to the Earth from other solar systems, which, however improbable is still remotely possible. Of course the more likely alternative is that life originated on the Earth. Even more fanciful is the development of his and Sir Fred Hoyle's theory that pretty much every microbial disease know to man is transported from space to the Earth, ready to infect unsuspecting populations. Wickramasinghe regales us with many examples of so called diseases that may have come from space, including the E. coli O157 outbreak in Scotland a few years ago. No mention is made in the book that the source of outbreak was traced to contamination from a butchers shop. This is the theme throughout the book; biological truth is cleverly interweaved with complete fiction. It is very difficult to write a review of the book without launching into a personal attack of the author. Wickramasinghe may genuinely believe his theories, fair enough, but to those who practice molecular biology and microbiology, he sounds like a charlatan of old. This book will appeal to the pseudoscientists, who treat astrology as a science, but to the rest of us it will be a waste of money--or a good April fools day present. _____________________________________________________________________ BOOK REVIEW: EARTH, LIFE AND THE UNIVERSE... EXPLORING OUR COSMIC ANCESTRY By Julian Hiscox 29 July 2002 Title: Earth, Life and the Universe... Exploring Our Cosmic Ancestry Author: Keith Tritton Publication Date: 2001 Publisher: Curved Air Publications ISBN: 0-9540991-0-9 Since the furore over ALH84001 and the formation of NASA's astrobiology program, the study of the origin of life and its associated subjects has become the subject of a large number of books, some are worth reading, but a number should be consigned to the bin. Many of the books have been written by biologists and others by scientists new to biology but eager to stamp their ideas on the subject. Indeed, the study of astrobiology should not, and is not, confined to the discipline of biology. Keith Tritton, an astronomer, has now pitched into the fray. His book is like a blast of fresh air. The contents are logically set out and clearly explained. He starts with the chapter "Cosmic Cycle" and explains why the sun is fundamental to life on the Earth; he then follows the development of that life and expands his analysis to possible life on Mars and beyond the habitable zone (the region surrounding the Sun in which liquid water is theoretically stable). This book does not cover all aspects of astrobiology but provides one of the most reader friendly overviews of the subject area. There are a number of topics in which I would like to debate with the author, including his views on where life originated (he subscribes to the panspermia school), and his ideas on the speed of evolution. The only real niggle I had with book were the very narrow page margins next to the spine-- something I hope the publishers will correct if there is a second edition. _____________________________________________________________________ BOOK REVIEW: X15--THE NASA MISSION REPORTS By Julian Hiscox Title: X15--The NASA Mission Reports Author: Robert Godwin Publication date: 2000 Publisher: Apogee Books ISBN: 1-896522-65-3 It was Tom Cruise's character, Maverick, in the film Top Gun, who famously remarked, "I feel the need, the need for speed." In fact, the top speed of any present day fighter or commercial aircraft pales into insignificance when compared to the X-15, which was a hybrid aircraft/rocket developed and flown in the nineteen fifties and early 'sixties. Back when the space race was young, there were two competing programs in the USA, NASA's (Project Mercury) and the United States Air Force's, which would have culminated in the launch of the X-20, or Dyna-Saur. The Air force's rationale was to have a reusable multipurpose space plane that could be used for reconnaissance, as an orbital bomber and so on. One of the stepping- stones to the X-20 was the X-15, and Robert Godwin has yet again compiled an excellent account of this most fascinating spaceplane. Launched from a B52, the X-15 pilot lit the rocket motor and enjoyed a roller coaster sub-orbital ride into the outer fringes of the atmosphere. In fact some X-15 pilots flew so high--up to 354,000 feet--that they were awarded USAF astronaut wings. Such lobs were comparable to Alan Shepard's first Mercury flight. Much of the research conducted using the X-15 was directly relevant to the shuttle: how to steer using reaction control rockets rather than ailerons, hypersonic re-entry into the atmosphere and so on. The book provides pilot biographies, and when the X-15 project wound down and the X-20 was cancelled, many of the pilots transferred over to the space program (e.g. Neil Armstrong and Joe Engle). Although Godwin's book may initially appear not for the faint hearted, and contains detailed engineering data, it also contains many "oh wow" facts, and is well worth buying. _____________________________________________________________________ NEW ADDITIONS TO THE ASTROBIOLOGY INDEX By David J. Thomas http://www.lyon.edu/webdata/users/dthomas/astrobiology/astrobiology.h tml 29 July 2002 Astrobiology, exobiology and terraformation articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_article s1.html Astrobiology Magazine Staff, 2002. Lifetime of complex life. Great debates part IV. Astrobiology Magazine. Astrobiology Magazine Staff, 2002. Relentless evolution. Great debates part V. Astrobiology Magazine. Terrestrial extreme environments articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_article s2.html Harbor Branch Oceanographic Institution, 2002. Stealthy new deep-sea camera system may find new life-forms. SpaceDaily. T. Malik, 2002. Observing "alien" life on Earth. Space.com. Human space exploration and microgravity effects articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_article s3.html P. Scott, 1999. This old space station. Scientific American, 281(3). Search for extraterrestrial intelligence (SETI) articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_article s4.html S. Shostak, 2002. Is E.T.'s world a planet? Space.com. Evolutionary biology and chemistry articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_article s5.html R. R. Britt, 2002. Evidence for ancient bombardment of Earth. Space.com. R. R. Britt, 2002. Moon holds Earth's ancient secrets. Space.com. University of Queensland, 2002. First evidence for early meteorite bombardment of Earth. SpaceDaily. _____________________________________________________________________ CASSINI SIGNIFICANT EVENTS NASA/JPL release 18-24 July 2002 The most recent spacecraft telemetry was acquired from the Goldstone tracking station on Wednesday, July 24. The Cassini spacecraft is in an excellent state of health and is operating normally. Information on the present position and speed of the Cassini spacecraft may be found on the "Present Position" web page located at http://saturn.jpl.nasa.gov/cassini/english/where/. This week the spacecraft transitioned to the Reaction Control Subsystem and the use of thrusters for attitude control, and powered off the Reaction Wheel Assembly. In addition, an autonomous Solid State Recorder memory load partition repair was performed along with a clearing of the ACS high water marks. Instrument activities included a Visual and Infrared Mapping Spectrometer star characterization, an Ultraviolet Imaging Spectrograph Hydrogen Deuterium Absorption Cell conditioning activity, a Composite InfraRed Spectrometer thermal calibration, and calibrations of the Radio and Plasma Wave Science high frequency receiver. The Cassini Program released a media report on the Imaging Science Subsystem haze anomaly in the Narrow Angle Camera (NAC). Analysis of data obtained over the last few weeks confirms image quality has returned to virtually the same as prior to when the haze appeared. The haze was first observed when the NAC cooled back to its usual operating temperature after a routine maintenance heating to 30 C in mid-2001. Lens hazing from engine exhaust or other sources is always a possibility on interplanetary spacecraft and instrument designers incorporate heaters into the camera assembly to cope with just such a situation. Four decontamination treatments over varying lengths of time removed most of the haze. In the latest activity, the camera was warmed to 4 degrees C for four weeks ending July 9. Images were then taken at the normal operating temperature of minus 90 C, confirming the removal of the haze. Comparison images are available for viewing at http://www.jpl.nasa.gov/images/cassinicamera_caption.html. Uplink Operations offered a course in the use of Cassini's Pointing Design Tool to Composite InfraRed Spectrometer instrument team personnel at the Goddard Spaceflight Center. A Development tour planning retreat was held to ensure that all development schedules for achieving tour readiness were consistent and realistic, dependencies understood and agreed-to, risks identified, and work prioritized. Cassini is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, CA, manages the Cassini mission for NASA's Office of Space Science, Washington, DC. _____________________________________________________________________ CONTOUR STATUS REPORT NASA/JHUAPL release http://www.contour2002.org/ 19 July 2002 This week was a relatively quiet one for the mission operations team. There were no propulsive attitude maneuvers or orbit maneuvers planned. The team monitored the spacecraft daily and has been assessing its spacecraft's performance by analyzing the telemetry beamed down from orbit. The spacecraft transmits hundreds of telemetry parameters every second such as: report voltages, currents, temperatures, sun angles, spin rates, pressures, etc. All of these parameters are checked for proper values and also for trends that may signal something going wrong in the future. So far, the data shows that everything is working wonderfully. When the team is not assessing the health of the spacecraft, it is busy planning and testing upcoming activities. In preparation for the upcoming solid rocket motor burn, the team must have the spacecraft execute a series of propulsive maneuvers that place the spacecraft in the correct position in orbit and also pointed precisely in the right direction. Before any of these burns are executed on the spacecraft, they are tested on simulators in the mission operations center to show that the spacecraft will perform them correctly and also that the outcome produces the desired results. The spacecraft is currently spinning at 20.0 rpm with a mast Sun angle of 63 degrees. The Sun is favoring the spacecraft's top end, which is covered with solar cells. _____________________________________________________________________ CONTOUR CHANGING ITS ATTITUDE NASA/JHUAPL release http://www.contour2002.org/news.php?id=14 26 July 2002 CONTOUR's latest move was a flop--and spacecraft operators couldn't be happier. On July 24, CONTOUR pulled off the first two installments of a six-part "flop" maneuver designed to gradually aim its onboard rocket for the critical firing that will boost the spacecraft out of Earth orbit on August 15. Mission operators had "flipped" CONTOUR shortly after its July 3 launch for a maneuver that set the timing of its current orbit around Earth. "Now we're going back the other way so the solid rocket motor is pointed in the right direction," says Mark Holdridge, CONTOUR mission operations manager at the Johns Hopkins Applied Physics Laboratory. Each two-hour stage of the flop required more than 1,100 short bursts from CONTOUR's thrusters. Mission planners have spread the four remaining steps over the next 10 days, including them among several maneuvers to adjust the size and shape of CONTOUR's orbit. With each 42-hour loop around Earth - and a lot of help from the mission team members who design and execute the maneuvers--CONTOUR slowly moves into the exact position for the "second launch" that starts it on its path around the Sun and, eventually, toward its target comets. "The maneuvers are all set up so that you have the right orbit and you can get to the right point at the right time," Holdridge says. _____________________________________________________________________ INTERNATIONAL SPACE STATION SCIENCE OPERATIONS STATUS REPORT NASA/MSFC release 24 July 2002 The Expedition Five crew has successfully completed a manufacturing experiment that could lead to an improved method of drug delivery in the body. A total of eight samples were processed last Thursday and Friday in the Microencapsulation Electrostatic Processing (MEPS) experiment, said MEPS Principal Investigator Dr. Dennis Morrison, with the Medical Sciences Division at NASA's Johnson Space Center in Houston. "All data and the microcapsules produced during the experiment runs will be returned on the STS-112 Space Shuttle mission," Morrison said. "The experiment appeared to run without any anomalies. We are very anxious to get back our samples and start analyzing them." The first four experiment runs last Thursday studied the encapsulation process, using different modes of mixing dissimilar fluids to create microcapsules for two different formulations of a light-activated anticancer drug derived from a porphyrin molecule isolated from blood, Morrison said. To treat cancers, this drug is injected into blood vessels leading to the tumor where it is preferentially absorbed by tumor cells and later activated by applying near-infrared light that penetrates deep into tissues. Superoxides released by the light then kill the tumor cells. The fifth experiment Thursday encapsulated DNA from genetically engineered E. coli bacteria. Two experiment runs on Friday encapsulated a mix of two anti-cancer drugs and tiny ferromagnetic particles that would allow doctors to trigger them with a magnetic field to release their drugs into tumor tissues. The third experiment Friday encapsulated the same drug mixture without trigger particles and then a high voltage electrostatic field was used to deposit a thin polymer coating onto the microcapsule outer membrane. The automated MEPS experiment cures, filters, washes and harvests the microcapsules for analysis on the ground. Experiments such as this could eventually lead to the development of anti-tumor drugs that allow the delivery of higher doses of chemotherapeutic drugs to specific treatment sites, reducing the unwanted side effects experienced by cancer patients. "The MEPS experiments in microgravity are conducted to better understand the manufacturing process on Earth, where the gravity- induced sedimentation of the different density components greatly confuses the understanding of what conditions, fluid flow, temperature, etc. produce the most uniform microcapsules with the maximum drug loading," Morrison said. "Thus, we are not just checking out hardware, but making microcapsules for further study and to develop large scale production techniques so that companies can make these for various types of drug deliveries into human and veterinary patients." The Protein Crystal Growth Single Thermal Enclosure System (PCG-STES) experiment completed processing one sample on Friday. Four other sample processing cylinders remain active in this experiment to grow biological materials for study on the ground and possible applications in medicine and agriculture. On Tuesday, the Station science team initiated the second of 10 planned tests with the Solidification Using a Baffle in Sealed Ampoules (SUBSA) experiment. The furnace failed to heat properly during the run, possibly due to a software error that can be resolved by ground commanding. The science team and controllers are troubleshooting today. Additional troubleshooting may replace another experiment run planned for Thursday. SUBSA is the first of two Expedition Five materials science experiments that will study basic physical processes similar to those used to make semiconductors for electronic devices and components used in jet engines. A total of 10 samples will be processed during the Expedition. The experiment also was monitored by a portable vibration sensor located in the Microgravity Science Glovebox and connected to the Space Acceleration Measurement System (SAMS), located in EXPRESS Rack 1. Flight Engineer Peggy Whitson changed out the SAMS hard drive and battery last week to ensure that the portable sensor operated correctly during the run. SAMS supports many of the experiments onboard by characterizing the microgravity environment. Also on Tuesday, Commander Valery Korzun and Whitson set up and conducted the Pulmonary Function in Flight (PuFF) lung function test. Each PuFF session includes five lung function tests. The focus is on measuring changes in the evenness of gas exchange in the lungs, and on detecting changes in respiratory muscle strength. A decrease in the evenness of gas exchange is a hallmark of virtually every acute condition and disease of the pulmonary system. Changes in respiratory muscle strength may result from long periods in the absence of gravity. The results will help in maintaining crew health during long space missions. The crew today (Wednesday) was scheduled to conduct their weekly Crew Interactions survey on the Human Research Facility laptop computer. The Interactions experiment will identify and characterize important interpersonal and cultural factors that may impact the performance of the crew and ground support personnel during International Space Station missions. On Thursday, the crew is scheduled to collect background radiation readings for the EVA Radiation Monitoring (EVARM) experiment and then transfer the measurements to a laptop computer to be downlinked later that day. On Friday, the crew is scheduled to participate in and videotape a session with the Education Payload Operations experiment. For this activity, they will use a variety of simple toys to illustrate basic principles of physics. Crew Earth Observations photography subjects this week included: fires in Zimbabwe, air quality in industrialized southeastern Africa, and vegetation in the Parana River basin. The number of photo targets is expected to be reduced for several weeks as the Station's orbital path carries it over the shadow-darkened winter of the Southern Hemisphere. Other experiments under way in the Destiny laboratory module continue to function normally. The Payload Operations Center at NASA's Marshall Space Flight Center in Huntsville, AL, manages all science research experiment operations aboard the International Space Station. The center is also home for coordination of the mission-planning work of a variety of international sources, all science payload deliveries and retrieval, and payload training and payload safety programs for the Station crew and all ground personnel. Contact: Steve Roy Media Relations Department Phone: 256-544-0034 E-mail: Steve.Roy@msfc.nasa.gov _____________________________________________________________________ MARS ODYSSEY THEMIS IMAGES NASA/JPL/ASU release 22-26 July 2002 Frosted Sand Dunes (Released 22 July 2002) http://themis.la.asu.edu/zoom-20020722a.html Nepenthes Mensae (Released 23 July 2002) http://themis.la.asu.edu/zoom-20020723a.html The So-Called "Face on Mars" in Infrared (Released 24 July 2002) http://themis.la.asu.edu/zoom-20020724A.html Acidalia Planitia (Released 25 July 2002) http://themis.la.asu.edu/zoom-20020725a.html Pandora Fretum Crater (Released 26 July 2002) http://themis.la.asu.edu/zoom-20020726a.html All of the THEMIS images are archived at http://themis.la.asu.edu/latest.html. NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. Dr. Philip Christensen leads the THEMIS investigation at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena. _____________________________________________________________________ STARDUST STATUS REPORT NASA/JPL release 26 July 2002 There were two Deep Space Network passes this past week and all subsystems are normal. Thursday's early morning communications track was an NSP (Network Simplication Project) radio metric engineering test at Goldstone, California. The Navigation team had to condition their data first, but the "best efforts" telemetry data appears to be good. The internal Comet Wild 2 Fault Tree Review identified and analyzed over 230 potential events. The review also showed areas where additional analysis will be required but no showstoppers were identified. Work on the analysis continues. For more information on the Stardust mission--the first ever comet sample return mission--please visit the Stardust home page at http://stardust.jpl.nasa.gov. _____________________________________________________________________ End Marsbugs, Volume 9, Number 29.