MARSBUGS: The Electronic Astrobiology Newsletter Volume 10, Number 3, 20 January 2003. Editor/Publisher: David J. Thomas, Ph.D., Science Division, Lyon College, Batesville, AR 72503-2317, USA. dthomas@lyon.edu Contributing Editor: Julian A. Hiscox, Ph.D., 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 effectively 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/. ________________________________________________________________________ CONTENTS 1) SNOW ALGAE ABSORB GREENHOUSE GAS By Sarah Graham 2) EARTH LIKELY SPARED FROM ONE FORM OF COSMIC DOOM NASA/GSFC release 3) "THE END OF THE WORLD" HAS ALREADY BEGUN, UW SCIENTISTS SAY By Vince Stricherz 4) DINOSAURS EXPERIENCED CLIMATE CHANGES BEFORE K-T COLLISION Pennsylvania State University release 5) NASA AMES FLIGHT RESEARCH TO FOCUS ON FUNDAMENTAL BIOLOGY NASA/ARC release 03-05AR 6) "MOSS IN SPACE" PROJECT TO TEST HOW PLANTS GROW "UP" By Earle Holland 7) MARS AND THE FINAL FOUR NASA/JPL release 8) SCIENCE THAT CAN'T BE DONE ON EARTH By Tony Phillips 9) VITAL SIGNS OF LIFE ON DISTANT WORLDS ESA release 10) CHINA PLANS FIRST MANNED SPACE LAUNCH IN OCTOBER From Agence France-Presse and SpaceDaily 11) MARS DESERT RESEARCH STATION CREW 11 GIVES PARTING COMMENTS Mars Society release 12) PATIENT SIMULATOR WILL ENHANCE TRAINING FOR MEDICAL EMERGENCIES IN SPACE NSBRI release 13) COMPLEX LIFE, BY JOVE! By Leslie Mullen 14) NEW ADDITIONS TO THE ASTROBIOLOGY INDEX By David J. Thomas 15) CASSINI SIGNIFICANT EVENTS NASA/JPL release 16) INTERNATIONAL SPACE STATION SCIENCE OPERATIONS STATUS REPORT NASA/MSFC release 03-009 17) MARS ODYSSEY THEMIS IMAGES NASA/JPL/ASU release 18) STARDUST STATUS REPORT NASA/JPL release ________________________________________________________________________ SNOW ALGAE ABSORB GREENHOUSE GAS By Sarah Graham From Scientific American 7 January 2003 The unicellular alga Chlamydomonas nivalis leaves its mark on snowfields with a telltale pinkish hue. The red algae typically live at altitudes higher than 2,500 meters and temperatures below freezing. Despite such harsh conditions and correspondingly high radiation levels, C. nivalis can remove carbon dioxide from its surroundings through photosynthesis. Indeed, scientists report this week in the online edition of the Proceedings of the National Academy of Sciences that "gas-exchange from snow-algae-covered areas might represent a small but significant global carbon sink not previously noted, because summer snowfields cover significant areas of the Earth." Read the full article at http://www.scientificamerican.com/article.cfm?chanID=sa003&articleID=000 A3F82-EFAB-1E19-8B3B809EC588EEDF. ________________________________________________________________________ EARTH LIKELY SPARED FROM ONE FORM OF COSMIC DOOM NASA/GSFC release 8 January 2003 We have one less thing to worry about. While the cosmic debris from a nearby massive star explosion, called a supernova, could destroy the Earth's protective ozone layer and cause mass extinction, such an explosion would have to be much closer than previously thought, new calculations show. Scientists at NASA and Kansas University have determined that the supernova would need to be within 26 light years from Earth to significantly damage the ozone layer and allow cancer-causing ultraviolet radiation to saturate the Earth's surface. An encounter with a supernova that close only happens at a rate of about once in 670 million years, according to Dr. Neil Gehrels of NASA's Goddard Space Flight Center in Greenbelt, MD, who presents these findings today at the American Astronomical Society meeting in Seattle. "Perhaps a nearby supernova has bombarded Earth once during the history of multicellular life with its punishing gamma rays and cosmic rays," said Gehrels. "The possibility for mass extinction is indeed real, yet the risk seems much lower than we have thought." The new calculations are based largely on advances in atmospheric modeling, analysis of gamma rays produced by a supernova in 1987 called SN1987a, and a better understanding of galactic supernova locations and rates. A supernova is an explosion of a star at least twice as massive as our Sun. Previous estimates from the 1970s stated that supernovae as far as 55 light years from Earth could wipe out up to 90 percent of the atmosphere for hundreds of years. The damage would be from gamma rays and cosmic rays, both prodigiously emitted by supernovae. Gamma rays are the most energetic form of light. Cosmic rays are atomic particles, the fastest- moving matter in the Universe, produced when the expanding shell of gas from the exploded star runs into surrounding dust and gas in the region. Gamma rays, moving at light speed, would hit the Earth's atmosphere first, followed closely by the cosmic rays moving at close to light speed. Gamma-ray light particles (called photons) and the cosmic-ray particles can wreak havoc in the upper atmosphere, according to Dr. Charles Jackman of NASA Goddard, who provided the atmospheric analysis needed for the new calculation. The particles collide with nitrogen gas (N2) and break the molecule into highly-reactive nitrogen atoms (N). The nitrogen atoms then react fairly quickly with oxygen gas (O2) to form nitric oxide (NO) and, subsequently, other nitrogen oxides (NOx). The nitrogen oxide molecules can then destroy ozone (O3) through a catalytic process. This means that a single NOx molecule can destroy an ozone molecule and remain intact to destroy hundreds of more ozone molecules. The new calculations--based on the NASA Goddard two-dimensional photochemical transport model--show that a supernova within 26 light years from Earth could wipe out 47 percent of the ozone layer, allowing approximately twice the amount of cancer-causing ultraviolet radiation to reach the Earth's surface. Excessive UV radiation is harmful to both plants and animals, thus a doubling of UV levels would be a significant problem to life on Earth. The gamma-ray irradiation would last 300 to 500 days. The ozone layer would then repair itself, but only to endure cosmic-ray bombardment shortly after, lasting at least 10 years. (Cosmic rays are electrically charged particles whose paths are influenced by magnetic fields, and the extent of such fields in the interstellar medium is not well understood.) The calculations simultaneously point to the resilience of the ozone layer as well as its fragility in a violent Universe, said Dr. Claude Laird of the University of Kansas, who developed the gamma-ray and cosmic ray input code and performed the atmospheric model simulations. Although the ozone layer should recover relatively rapidly once the particle influx tapers off--within about one to two years, the Goddard models show--even this short period of time is sufficient to cause significant and lasting damage to the biosphere. "The atmosphere usually protects us from gamma rays, cosmic rays, and ultraviolet radiation, but there's only so much hammering it can take before Earth's biological defenses break down," he said. Dr. John Cannizzo of NASA Goddard and University of Maryland, Baltimore Country, initiated and coordinated the new calculations. "I've long been fascinated by the possibility of extinction from something as remote as a star explosion," he said. "With this updated calculation, we essentially worked backwards to determine what level of ozone damage would be needed to double the level of ultraviolet radiation reaching the Earth's surface and then determined how close a supernova would need to be to cause that kind of damage." These results will appear in the Astrophysical Journal, 10 March 2003, volume 585. Co-authors include Barbara Mattson of NASA Goddard (via L3 Com Analytics Corporation) and Wan Chen of Sprint IP Design in Reston, Virginia. The original press release, with images, is available at http://www.gsfc.nasa.gov/topstory/2003/0108supernova.html. An additional article on this subject is available at http://www.spacedaily.com/news/supernova-03b.html. ________________________________________________________________________ "THE END OF THE WORLD" HAS ALREADY BEGUN, UW SCIENTISTS SAY By Vince Stricherz University of Washington release 13 January 2003 In its 4.5 billion years, Earth has evolved from its hot, violent birth to the celebrated watery blue planet that stands out in pictures from space. But in a new book, two noted University of Washington astrobiologists say the planet already has begun the long process of devolving into a burned-out cinder, eventually to be swallowed by the sun. By their reckoning, Earth's "day in the sun" has reached 4:30 AM, corresponding to its 4.5 billion-year age. By 5:00 AM, the 1 billion- year reign of animals and plants will come to an end. At 8:00 AM the oceans will vaporize. At noon--after 12 billion years--the ever- expanding sun, transformed into a red giant, will engulf the planet, melting away any evidence it ever existed and sending molecules and atoms that once were Earth floating off into space. "The disappearance of our planet is still 7.5 billion years away, but people really should consider the fate of our world and have a realistic understanding of where we are going," said UW astrophysicist Donald Brownlee. "We live in a fabulous place at a fabulous time. It's a healthy thing for people to realize what a treasure this is in space and time, and fully appreciate and protect their environment as much as possible." In The Life and Death of Planet Earth, Brownlee and UW paleontologist Peter Ward use current scientific understanding of planets and stars, as well as the parameters of life, to provide a glimpse of the second half of life on Earth and what comes after. The book, a sort of biography of our planet, is being published today by Times Books, a division of Henry Holt and Co. It is a sequel to Ward and Brownlee's best-selling and much-discussed book, Rare Earth, in which they put forth the hypothesis that simple life is relatively common in the universe but complex, Earth-like life is exceedingly rare. The Life and Death of Planet Earth explains how the myriad life on Earth today was preceded by a long period of microbial dominance, and the authors contend that complex life eventually will disappear and be succeeded again by a period of only microbial life. They say that higher life will be removed much as it came into being, ecosystem by ecosystem. Aspects of the planet's past, such as numbingly cold ice ages, will be relived in the period of devolution. "If we do begin to slide into the next glacial cycle, there probably are grand, planetary-scale engineering projects that might stop or lessen the effects," Ward said. "The big unknowns are whether we can afford to do such projects and would we really know what to do. If the planet was cooling, we could, in principle, begin painting the surface black to collect more heat. Could we afford it? And what would be the many possible ramifications of a planet suddenly covered in black paint? Any planetary remediation project would always run the risk of making things worse." Eventually, though, scorching heat will drive land creatures to the sea for respite. Those that can adapt will survive for a time, but eventually the oceans will warm too much for the complex life forms to continue. "The last life may look much like the first life--a single-celled bacterium, survivor and descendant of all that came before," the authors write. Finally, even the surviving microbes "will be seared out of existence." The prospects of humans surviving by moving to some other habitable planet or moon aren't good, Brownlee and Ward contend, because even if such a place were found, getting there would be a huge obstacle. Various probes sent into space could survive Earth's demise, and just a few grams of material could arguably carry a DNA sample from every human, they say, but it's not likely the human species itself will survive. Long before the planet's final end, life will become quite challenging, and finally impossible, for humans. As the sun gets hotter and grows in size, it will envelop Mercury and Venus. It is possible it will stop just short of Earth, the authors say, but the conditions still would make this a most-inhospitable planet. More likely, though, the sun will consume Earth as well, severing all the chemical bonds between molecules and sending its individual atoms out into space, perhaps eventually to form new planets. That would leave Mars as the nearest planet to the sun, and on Mars the fading sun's glow would be like that of Earth's moon. That end is still some 7.5 billion years distant, but by then Earth will have faced a variety of "ends" along the way, the authors say. The last dinosaur perished long ago. Still to come are the last elephant, the last tree, the last flower, the last glacier, the last snowflake, the last ocean, the last life. The Life and Death of Planet Earth is like its predecessor, Rare Earth, in that the authors collected and distilled some of the latest scientific ideas about the Earth's place in the universe, Brownlee said. He hopes the new book, like Rare Earth, will spark widespread discussion, and give people a fundamental and realistic view of the past and future of their planet. "It's a healthy thing to think of the place of Earth among the other planets, and its place in the sun. The sun gave life and ultimately it will bring death." Contacts: Donald Brownlee Phone: 206-543-8575 E-mail: brownlee@bluemoon.astro.washington.edu Peter Ward Phone: 206-543-2962 E-mail: argo@u.washington.edu Vince Stricherz Phone: 206-543-2580 E-mail: vinces@u.washington.edu The original press release is available at http://www.washington.edu/newsroom/news/2003archive/01- 03archive/k011303a.html. Additional articles on this subject are available at: http://www.spacedaily.com/news/end-03a.html http://www.spacedaily.com/2003/030114174841.qeinalqe.html http://spaceflightnow.com/news/n0301/15earthclock/ The Life and Death of Planet Earth is available on The Astrobiology Index at http://www.lyon.edu/webdata/users/dthomas/astrobiology/astrobiology_book s.html#V-Z ________________________________________________________________________ DINOSAURS EXPERIENCED CLIMATE CHANGES BEFORE K-T COLLISION Pennsylvania State University release 14 January 2003 Climate change had little to do with the demise of the dinosaurs, but the last million years before their extinction had a complex pattern of warming and cooling events that are important to our understanding of the end of their reign, according to geologists. "The terrestrial paleoclimate record near the K-T is historically contradictory and poorly resolved," says Dr. Peter Wilf, assistant professor of geosciences at Penn State. "In contrast, the resolution of K-T marine climates that has emerged over the last 10 years is excellent. Our work brings the terrestrial record up to speed so that we can look for global climate events that occurred for both land and sea." Wilf worked with Kirk R. Johnson, curator of paleontology, Denver Museum of Nature & Science, who provided the data on land plant fossils and Brian T. Huber, curator of Foraminifera, National Museum of Natural History, Smithsonian Institution, who provided the marine data. An extraterrestrial object that impacted the Earth near the Yucatan in Mexico 65.51 million years ago doomed the dinosaurs and 70 percent of the Earth's other species, vaporizing itself and the surrounding rocks and throwing enough ash, soot and debris into the atmosphere to effectively stop photosynthesis worldwide. This impact radically altered the natural progression of evolution. The time of the impact is called the K-T boundary and marked the end of Cretaceous Period and the beginning of the Tertiary Period. "It could be argued that we are still recovering from that impact and the mass extinctions of dinosaurs, mammals, insects, plants and sea life that it caused," says Wilf, who worked on this project at the University of Michigan before coming to Penn State. "For example, not only the dinosaurs, but also 80 to 90 percent of the Cretaceous plant species, including all the dominant species, disappeared." According to Wilf, there is a lingering minority argument that the K-T extinction was caused by climate change, but the research team's results, published in a recent issue of the Proceedings of the National Academy of Sciences, both document the climate changes and show that they were not the principal cause. Wilf, Johnson and Huber first worked to create a finely resolved terrestrial temperature record, based on plant fossils, and then correlated that record with the existing marine records. Plant fossils from the one million-year period before the extinction that are abundant and well preserved in a fine time sequence are found only in New Mexico and North Dakota. Of the two, the North Dakota sites are comparably much more intensively collected and studied and enabled Johnson to collect 22,000 plant fossils of more than 300 fossil plant species. "Only in the last year, with the publication of an entire volume filled with new research results on the Hell Creek Formation in North Dakota, can we do this work and tie the plant fossil record there to actual dates in millions of years rather than relative dates," says Wilf. Johnson is a co-editor and contributor for the Hell Creek volume. Fossils can be dated relatively by their position in the stratigraphy or layers of sediment using a simple rule. In undisturbed layers, the oldest fossils are in the lowest layers and the most recent fossils are in higher levels. Tying relative dates to real dates is not easy, especially keeping within the 100,000 year sensitivity available in the marine record, which comes from the scientific results of the ocean drilling program. Luckily, the K-T extinction occurred during a short interval in the Earth's magnetic pole reversals. Periodically, the Earth's poles switch polarity making North negative and South positive. Eventually, another switch occurs making North positive and South negative. A record of the Earth's paleomagnetism is recorded in the rocks as they are laid down. "Three hundred and thirty-three thousand years before the extinction, a pole reversal occurred," says Wilf. "Two hundred and seventy thousand years after the extinction, another reversal occurred." Because the researchers have three datable points--the two reversals and the K-T impact--they could attach ages to the layers and the fossils within and correlate the terrestrial and marine data at much finer resolution than ever before. Simply equating the layers, however, was not enough. The researchers needed to estimate the temperature of the environment in which each fossil grew. For the plants, this turned out to be simple, using a method first developed in 1915 that is still widely used today. Modern forests have two types of trees, those with toothed leaves and those with smooth leaves. The cooler the climate, the higher the percentage of species with toothed leaves. "The presence of palm species also suggests a warm climate as these plants cannot survive the ground freezing," says Wilf. The researchers found from the plants that the long, slow cooling that occurred for millions of years of the Late Cretaceous was broken by a warming event that began about 66 million years ago and peaked 300,000 to 100,000 years before the K-T collision. The temperatures then returned to baseline just before the collision and stayed nearly constant before and after the collision. The plant record agreed strongly with the marine data, which comes from ocean coring projects in the South Atlantic, Antarctica and off the shores of New Jersey and Florida, and is based on the oxygen isotope ratios in the skeletons of marine-shelled micropredators called Foraminifera. The colder the water, the more of the heavier oxygen isotope is incorporated in the calcium carbonate of the shells. The sediments that entomb the forams also record the paleomagnetic reversals around the K-T. Because the marine data come from four different locations and the terrestrial data from a fifth, the warming and cooling trends seem global, according to Wilf. The marine data also show that warm water forams migrated from the tropics as far as New Jersey and Antarctica. While the mean annual temperature in North Dakota today is 43 to 45 degrees Fahrenheit, during the warmest part of the warming episode, the mean annual temperature was from 65 to 68 degrees Fahrenheit. The North Dakota site was then at the same latitude as Quebec City, Canada, and not only palm trees, but alligators and turtles thrived too. "The K-T impact affected the Earth's living things severely and dramatically, but the climate changes right before the impact, by comparison, did not," says Wilf. "Understanding the climate and vegetation before the impact gives us insight into what kind of world the meteorite struck, and shows us that it was warming, cooling, lushly forested and otherwise functioning the way it always has done. The dinosaurs were well adapted to global warming and cooling, but not to giant speeding rocks from space." The American Chemical Society, National Science Foundation and Smithsonian Institution funded this research. Contacts: A'ndrea Elyse Messer Phone: 814-865-9481 E-mail: aem1@psu.edu Vicki Fong Phone: 814-865-9481 E-mail: vfong@psu.edu Peter Wilf Phone: 814-865-6721 E-mail: pwilf@geosc.psu.edu by e-mail. Kirk Johnson Phone: 303-370-6448 E-mail: Kjohnson@dmns.org Brian Huber Phone: 202-786-2658 E-mail: Huber.Brian@nmnh.si.edu Read the original press release at http://www.psu.edu/ur/2003/cretaciousclimatechange.html. An additional article on this subject is available at http://www.spacedaily.com/news/early-earth-03a.html. ________________________________________________________________________ NASA AMES FLIGHT RESEARCH TO FOCUS ON FUNDAMENTAL BIOLOGY NASA/ARC release 03-05AR 14 January 2002 Understanding how the body adapts to space flight is the goal of four fundamental biology experiments set to fly on this month's space shuttle mission. The 16-day flight is dedicated to investigating human physiology and other areas of research beneficial to people on Earth. The flight payload will contain three Fundamental Rodent Experiments Supporting Health (FRESH) designed to examine the body's adaptation to microgravity. This includes cerebral spinal fluid and body fluid imbalance, central nervous system adaptation, and changes in blood vessels that affect the regulation of blood pressure. A fourth experiment will investigate how a common soil and water bacterium grows in microgravity. The STS-107 mission is scheduled to launch from NASA's Kennedy Space Center, FL, on January 16 on the space shuttle Columbia. "Gravity has been present throughout evolution and influences all biological and physiological systems," said Marilyn Vasques, STS-107 project scientist at NASA Ames Research Center, in California's Silicon Valley. "The opportunity to study these systems in the absence of gravity provides novel and fundamental insight into how these systems work." Dr. Michael Delp of Texas A&M University, College Station, will examine the physiological responses of individual blood vessels involved in blood flow and blood pressure regulation. In space, fluids shift from the lower to the upper parts of the body, which triggers changes within the cardiovascular system. Although appropriate in microgravity, these adaptations can cause problems such as dizziness or fainting when astronauts return to Earth. The study of the resulting vascular adaptations will yield essential information about the basic physiological responses of individual blood vessels. This information also will support development of treatments or countermeasures to improve the health and performance of astronauts when they return to Earth. Dr. Jacqueline Gabrion of the Universite Pierre et Marie Curie, Paris, will study the production of choroidal cerebral spinal fluid in rats after exposure to microgravity. The distribution of fluids in the body changes as the body adapts to microgravity. Previous spaceflight experiments suggest that choroidal cerebral spinal fluid production is reduced in rats exposed to microgravity. This experiment will contribute to a better understanding of basic mechanisms that regulate body fluid balance. It also will provide an opportunity to investigate the mechanisms of adaptation that involve fluid balance in the brain, kidneys and lungs. Dr. Gay Holstein of New York's Mount Sinai School of Medicine will investigate changes in the brain's cerebellar cortex that accompany adaptation to altered gravity. Changes in astronaut sensory and motor function, including space adaptation syndrome and sensations of rotation, dizziness and vertigo, occur during and following exposure to microgravity. Adaptation to the microgravity environment usually occurs within one week, and a re-adaptation period of several days often is required upon return to Earth. The results of this experiment will help identify the cellular causes of changes in the balance system that occur during adaptation and re-adaptation to different gravitational forces. Dr. Barry Pyle of Montana State University, Bozeman, will investigate a common soil and water bacterium, Pseudomonas aeruginosa. His study will provide insight into the growth, physiology and toxin production of this diverse group of microorganisms that is widely distributed in the environment and part of the normal intestinal flora of healthy humans. Previous research has shown that bacteria grow faster in space than on Earth and that the ability of certain antibiotics to control bacterial infections may differ greatly in space. A better understanding of these bacteria may lead to improved treatment and prevention of infections. The European Space Agency provided the hardware for this experiment. "NASA Ames is providing three Animal Enclosure Modules (AEMs), which will house the rats in the FRESH experiments," said Rudy Aquilina, NASA Ames' STS-107 project manager. Although 41 AEMs have flown on 21 previous space shuttle missions, this is the first AEM flight in the Spacehab module. "The team has worked hard preparing for this flight and is excited about the science that will be returned from this fundamental biology life sciences mission," Aquilina said. Understanding the many physiological adaptations that occur in microgravity is essential for developing treatments and countermeasures to improve crew health and performance in space and following return to Earth. Blood vessel changes seen in microgravity may resemble cardiovascular changes associated with aging, and the short- and long- term changes in neural structure that occur during adaptation to microgravity resemble those found in certain neurological disorders. Sponsored and funded by NASA's Office of Biological and Physical Research, the studies are part of NASA's effort to use the microgravity environment of space to advance knowledge in ways that cannot be achieved on Earth. Details about STS-107 research are available at http://spaceresearch.nasa.gov/. Further information about NASA's fundamental biology program is available at http://fundamentalbiology.arc.nasa.gov. Details about the STS-107 mission are available at www.spaceflight.nasa.gov. Contact: Victoria Steiner NASA Ames Research Center, Moffett Field, CA Phone: 650-604-0176 or 650-604-9000 E-mail: Victoria.L.Steiner@nasa.gov An additional article on this subject is available at http://www.spacedaily.com/news/spacemedicine-03a.html. ________________________________________________________________________ "MOSS IN SPACE" PROJECT TO TEST HOW PLANTS GROW "UP" By Earle Holland Ohio State University release 14 January 2003 An experiment scheduled for today's Space Shuttle Columbia mission may provide clues about just how plant growth is guided by gravity. The study, an extension of work from a previous shuttle mission in 1997, should test whether the absence of gravity changes how simple plants grow. The experiment will use common roof moss (Ceratodon purpureus), a plant that uses gravity to determine the direction that single cells grow. These tip cells will respond to both light and gravity, explained Fred Sack, professor of plant biology at Ohio State University. Light is the stronger of the two factors, but in the dark, the cells grow in the direction opposite the attraction of gravity. These are exceptional cells. It is rare for gravity to control the direction that single cells grow instead of an entire plant, Sack says. We wanted to know if they were placed in a near gravity-free environment, would the plants grow in a random fashion. The space shuttle offers us a laboratory to test that hypothesis. Sacks team got a partial answer from their 1997 shuttle experiments. Surprisingly, the cells growth was not random once gravity was removed. Moss cultures grown in orbit for two weeks in the dark during that flight produced elaborate clockwise spirals. We suspect that those spirals resulted from a residual spacing mechanism intended to control colony growth and the distribution of branches, Sack says, a mechanism that is normally suppressed by the stronger influence of gravity on earth. The current shuttle experiments are aimed at answering some of these questions. Forty-seven moss-containing Petri dishes will be grown in a self-contained, mid-deck locker. In one treatment, the moss will grow first in red light and then in the darkness to see how quickly spirals develop. At the center of the project is the question of how the cells sense gravity and how that event controls individual cell growth. Researchers have shown that it is likely that heavy organelles in the tip cells fall and somehow signal growth in the opposite direction. On earth, these organelles never completely settle to the bottom of the tip cells. They remain trapped in certain zones within the cells, apparently supported and contained by an intricate scaffold-like structure of microtubules and actin microfilaments within the cell. The earlier Shuttle experiment showed a surprising result that the organelles aggregated in clusters instead of being randomly located within the cell. One goal of this missions experiment is to determine if that microscopic scaffolding controls the clustering. The researchers will test this by injecting drugs that selectively break down the different types of protein fibers in the cells scaffolding. The researchers hope to determine whether the organelles still cluster together once the microscopic scaffolding is removed. "In space where there is minimal gravity, you'd expect a more random distribution of organelles within the cells," Sack said. "The presence of clusters in them while in space suggests that internal forces exist within the cell that gravity ordinarily overwhelms". Sack said, "This fiber-organelle relationship may be a specialization that the moss cells developed over time for gravity sensing. But it may also relate to understanding how most cells cope with internal mechanical forces." After the experiments are completed, the astronauts will chemically preserve the moss containers before returning to Earth. Upon landing, the Ohio State research team will take thousands of microscope pictures for later study. This research was supported by Fundamental Biology Program of the National Aeronautics and Space Administration. Along with Sack, Volker Kern, a postdoctoral fellow in plant biology at Ohio State, is a co- principle investigator on the project. Contacts: Fred Sack Phone: 614-292-0896 E-mail: sack.1@osu.edu Earle Holland Phone: 614-292-8384 E-mail: Holland.8@osu.edu Read the original release at http://www.osu.edu/researchnews/archive/mossinspace.htm. An additional article on this subject is available at http://www.spacedaily.com/news/food-03a.html. ________________________________________________________________________ MARS AND THE FINAL FOUR NASA/JPL release 14 January 2003 The launch dates for the two Mars Exploration Rovers are getting closer and so is the need to pick a place for them to land. Adventurous travelers might spin a globe and pick a vacation based on whichever spot their finger finds. But scientists and engineers working on NASA's newest rover mission cannot be as casual about landing site choices for the twin rovers that will launch in May and June of this year. Last week, team members and others from the scientific community met for a final chance to discuss and fine-tune the pros and cons of each of the four landing site contenders. Images and data from two other NASA spacecraft currently orbiting the red planet--Mars Global Surveyor and Mars Odyssey--have provided invaluable information on possible landing sites. "This is a unique period where we have orbital missions that can help us make the selection," said Dr. Matt Golombek, JPL landing site scientist. "We want to go to sites with terrains that will challenge our minds but not the safety of the rovers." Since the rovers do not have the luxury of landing on a well-paved runway, JPL geologists and engineers must carefully choose an area without large rocks that could damage the rovers' airbag landing system. Also, an area that is too densely populated with rocks of any size could prevent the rover from moving freely. Winds in the lower atmosphere are also an important consideration, as are the slopes the airbag-clad lander impact against. Adequate exposure to the sun is vital for the solar-powered rovers. Geologists have chosen sites near the equator where there is sufficient sunlight. The sites are also relatively free of accumulations of iron-oxide dust particles that can coat solar panels and interfere with the rovers' mobility. Like the final four in any competition, each of the four Mars candidates is a potential winner. "Three of the sites, Terra Meridiani, known as the Hematite site, Gusev, and Isidis show evidence for surface processes involving water. These sites appear capable of addressing the science objectives of the rover missions: to determine if water was present on Mars and whether there are conditions favorable to the preservation of evidence for ancient life," said Golombek. The fourth site, Elysium, appears to contain ancient terrain, which may hold clues to Mars' early climate when conditions may have been wetter. Over the next several months, geologists and engineers will continue to analyze the viability of each site. The final decision will be made by NASA in April, shortly before the rovers begin their journey to Mars. Read the original article at http://www.jpl.nasa.gov/solar_system/features/landingsites.cfm. Additional articles on this subject are available at: http://www.space.com/missionlaunches/mars_rovers_030110.html http://www.spacedaily.com/news/mars2003-03a.html ________________________________________________________________________ SCIENCE THAT CAN'T BE DONE ON EARTH By Tony Phillips From NASA Science News 16 January 2003 The year was 1643. Evangelista Torricelli, an assistant of Galileo, poured some mercury into a glass tube and put his thumb over one end. Then he tried to pour the mercury out, but it wouldn't come. A little void had formed between his thumb and the mercury; somehow it held the heavy liquid in place. He had discovered vacuum. Nowadays, kids in restaurants routinely do the same thing using straws and water or milk, but in Torricelli's day the notion of a vacuum was radical. Artistotle himself had declared that nature abhorred vacuums. Scientists, however, soon learned to love them. A laboratory vacuum chamber is like a piece of outer space on Earth. It's a wonderful place to do experiments that would be impossible in our planet's thick atmosphere. Research involving vacuums and air pressure has led to light bulbs, integrated circuits, freeze-dried foods, particle accelerators, electron microscopes--even weather forecasting and human flight. Torricelli would be amazed. It might be said that Torricelli's work marked the beginning of space research. "But there are many aspects of space we can't mimic on Earth," says Dr. John Charles of NASA's Johnson Space Center in Houston. "We can turn down air pressure in laboratory vacuum chambers and bombard samples with space-like radiation. We can't turn off gravity, though, or look down on Earth from above." Some experiments simply can't be done on Earth. That's why NASA is building the International Space Station, a full-time low-gravity research lab. It's also why NASA schedules space shuttle missions dedicated to scientific research. One such mission began this morning when the space shuttle Columbia (STS-107) blasted off carrying 80+ scientific experiments. About half are commercial, sponsored by businesses who hope to make the next big profit-making discovery. The rest are pure science. "We'll be doing experiments in fundamental physics, biology, firefighting, medicine, climate... the variety is impressive," says Charles, who is the STS-107 mission scientist. "Space is a truly alien environment. Many things behave differently up there." Flames are a good example. On Earth, flames have a teardrop shape caused by hot air rising in a gravitational field. On board a spaceship, however, flames break apart into little balls that move around like UFOs. They burn using almost no fuel--something researchers would like to replicate in gas-saving auto engines. One of the experiments on STS-107, called SOFBALL-2, will ignite some flame balls and measure their properties. Scientists hope to learn how they burn and what keeps them lit. Human brains are another example. An astronaut just arriving in orbit has some big adjustments to make. There is no "up" or "down." If you drop something it doesn't fall. And just try catching a ball tossed by a crewmate! The brain adapts to weightlessness by building "a model" or mental subroutine that tells the body how to interpret these very unusual experiences. Before long, sleeping upside down is no problem. No one knows how the brain constructs such models, but neuroscientists want to find out because many believe model-building is a key to everyday human learning. NASA researchers will study this process among STS-107 crewmembers. How different is space? Not even flowers smell the same. Perfume industry giant International Flavors and Fragrances (IFF) found that out in 1998 when they sent a miniature rose called "Overnight Scentsation" into orbit onboard the space shuttle Discovery (STS-95). The flower developed a "floral rose aroma" quite distinct from its normal odor on Earth. The new fragrance has since been incorporated into "Zen", a perfume produced by the Japanese company Shiseido. This time on STS-107 IFF scientists will send two flowers into orbit--a rose and an Asian rice flower. They hope the pair together will produce scents even more exotic than before. "Those are just three examples," says Charles. "There are about 77 more experiments onboard Columbia--all just as exciting." Managing so many experiments is a big job. To get it done, Columbia's crew of seven will be split into two teams, Blue and Red, which will work 12 hour shifts. This will allow research to take place 24 hours-a- day during the entire 16-day mission. All of the investigations onboard Columbia have some specific goal such as improving auto engines or discovering new aromas. But the big prizes, says Charles, are unknown. "No one in the 17th century could have predicted where Torricelli's simple experiment would lead. Similarly, no one can predict where low-gravity research will take us now." "It's almost certain, though, that anything we do predict from our rudimentary experience so far will be only a small fraction of the ultimate benefits." Read the original article at http://science.nasa.gov/headlines/y2003/16jan_sts107.htm?list52260. Additional articles on this subject are available at: http://spaceflightnow.com/shuttle/sts107/030116launch/ http://www.spacedaily.com/2003/030118041657.keigytvb.html ________________________________________________________________________ VITAL SIGNS OF LIFE ON DISTANT WORLDS ESA release 16 January 2003 Detecting Earth-sized planets is hard enough but how does an astrobiologist decide which of them are inhabited? Scientists are now working to understand what signals life might give off into space, so that when they do detect Earth-like planets they know what to look for. Our radio and television broadcasts have been leaking into space since the 1930s, when the first powerful emitters were constructed. However, you can do things the other way around as well. The Search for Extraterrestrial Intelligence (SETI) has used radio telescopes to listen to the cosmos for similar signals. Nowadays, astrobiologists are pinpointing more subtle signs that all life, not just intelligent life, might radiate into space. They call these telltale signatures "biomarkers". When ESA's Darwin mission begins sending back data in the next decade, biomarkers will help indicate whether neighboring planets are inhabited. If we only used radio waves as markers of life, this would exclude all forms of life that have not yet developed the means to emit radio waves. Life has been around for thousands of millions of years, but human beings have used radio waves for less than a century. Malcolm Fridlund, Project Scientist for ESA's Darwin mission says, "If other planets follow the Earth's pattern, it is much more likely that they will be inhabited by dinosaurs or even bacteria than by something that can count." In the 1970s, the British scientist James Lovelock pointed out that, just by breathing, life affects the composition of the Earth's atmosphere. He suggested looking for similar effects as a way to search with telescopes for life on other planets. You can study the composition of an atmosphere by splitting a planet's light into a rainbow of colours. This "spectrum" will contain dark lines made by various chemicals in the planet's atmosphere. Darwin's strategy is to look for oxygen because oxygen is used by some life forms and produced as waste by others. Scientists believe that without life, all free oxygen in a planet's atmosphere would disappear within just four million years, because it reacts so easily with other chemicals. "The best estimates suggest that Darwin will be able to detect the build-up of oxygen caused within a few hundred million years of life's origin," says Fridlund. Although Darwin will not detect oxygen directly, it will "see" ozone, a form of oxygen. It will also see carbon dioxide, water, and, in certain cases, methane. Fridlund says, "The general consensus is that if we find ozone, liquid water, and carbon dioxide simultaneously, it will be a very strong indicator of life's presence." The work will not stop once Darwin completes its survey of the nearest several thousand star-planet systems. Once it finds a living planet, the race will be on to understand the nature of its life forms. That means searching for more specific biomarkers. In future space missions, for example, scientists may use chlorophyll as a biomarker. This molecule allows plants and certain bacteria to use light as an energy source. "Finding the next generation of biomarkers is a very active field of research at the moment," says Fridlund. He can see a future in which space telescopes look for intelligent civilizations by searching for industrial pollution in a planet's atmosphere. This may sound like science fiction but for now, oxygen, carbon dioxide, and water will be good enough as indicators of life. Contact: Malcolm Fridlund ESA - Darwin Project Scientist ESTEC, The Netherlands Phone: +31 (0)71 565 4768 E-mail: malcolm.fridlund@esa.int ESA - Science Programme Communication Service Phone: +31 (0)71 565 3273 E-mail: irina.bruckner@esa.int Read the original release at http://sci.esa.int/content/news/index.cfm?aid=28&cid=1902&oid=31301. An additional article on this subject is available at http://spaceflightnow.com/news/n0301/16life/. ________________________________________________________________________ CHINA PLANS FIRST MANNED SPACE LAUNCH IN OCTOBER From Agence France-Presse and SpaceDaily 17 January 2003 China plans to launch its first manned space mission in October in the quest to become only the third country to send a human into orbit, an official at the country's space program told AFP Friday. "There are plans to launch Shenzhou V in October this year," said a research official at China Aerospace Science and Technology Corp., which develops the rocket carriers and the spacecraft. The official, who would only give his surname, Lee, said an exact date had yet to be decided. "This depends on a lot of things," he said. "But one thing's for sure, a manned Shenzhou V will be launched this year, around October." ...Chinese space officials have said they are working towards a permanently manned space station and a possible landing on the moon. While officials have stressed China's space industry is being developed "for the purpose of peaceful use of space," there are underlying military connotations. Read the full story at http://www.spacedaily.com/news/china-03e.html. An additional article on this subject is available at http://www.spacedaily.com/2003/030116045401.ur3sffbd.html. ________________________________________________________________________ MARS DESERT RESEARCH STATION CREW 11 GIVES PARTING COMMENTS Mars Society release 17 January 2003 The eleventh Crew of the Mars Desert Research Station will complete its rotation January 19. Prior to departure, the crew embers decided to give their parting observations, which are reproduced below. To find out more about the activities of this highly successful crew, visit the MDRS link on the Mars Society web site at www.marssociety.org, where complete daily reports and photos are available. Roger Thompson, Mission Commander, Crew 11 On any given hour we might discuss genetics, stellar evolution, paleontology, bio-morphology, bio-remediation, meteorological principles, ethics, or worldviews, but in the airlock, preparing for an EVA, we still tell elephant jokes. A remarkable journey comes to an end. Tiffany Vora, Executive Officer I have been blessed, not once, but twice, with fulfilling rotations with unbelievable crews. We know for a certainty that we leave the hab in an improved condition--one of the prerequisites for any MDRS crew. Katie and I rigorously documented the sampling of putative biological specimens, and we look forward to beginning our molecular analyses of these samples back on Earth. Most importantly, I have a group of colleagues--surely not just colleagues, but friends--with whom I will be in touch, on a deep level, for as long as men remain earthbound. Once we make the leap into space, who knows? Perhaps we'll be reunited. Eleven is a very lucky number. Gernot Groemer, HSO and Crew Astronomer Finishing the setup of the MDRS observatory was certainly the major workload for this rotation, building on the impressive work of Peter Detterline. However, changing the computer system once more forced us to do a lot of astronomical-engineering. Additionally, bad weather prevented us from making full use of the system, and a lack of equipment receiving the first wave from the radio telescope. The Medical Simulations were another first the MDRS and--in cooperation with MedOps- -brought us a wealth of new insights not discussed in the medical literature yet. All together, especially these experiments were both fun and created new insights into Space suit design and emergency medical procedures. Katie Harris, Biology Team Two weeks on Mars have come to an end. Spacesuits have been hung up with finality, samples have been packed away for analysis back on Earth, and we've taken the ATVs for one last spin. In a matter of days we'll be back in the real world and the Hab will truly seem as distant as an alien planet. I'm going to miss this place. I'll miss the satisfaction that only comes from trekking many martian miles in a spacesuit to return to the Hab tired, exhilarated, hungry, and with pockets full of samples. I'll miss the martian scenery--the golden glow of a setting sun on red rock, vast rolling expanses of dunes stretching to the horizon where sky meets sand, the hint of snow-capped mountains in the distance, the sculpted buttes and arches and canyons that surpass in beauty all human-created art. But above all, I'll miss being around such an extraordinary, inspiring, amazing group of people. With individuals like these folks working toward a human mission to Mars, I have no doubt that we will make it happen, and sooner rather than later. I look forward to a crew 11 reunion on Mars. Shahar Lazar, Crew Geologist What can I say? These two weeks on "Mars" will be remembered as a mind- boggling experience, I was exposed during those two weeks to many different and new situations. The crew is assembled from persons gathered across the entire globe, the main thing that connect them all is their ability to do something extraordinary--leave their work or studies and do something completely different just for the joy of the discovery of new things: new people, new environment, and a new way of life. I feel that these two weeks have changed me. I know that before this simulation I was not sure if scientific research was the right path for me. Now I know after spending two wonderful weeks with people who speak the same language (and by that I do not mean English) that I chose the right path. I am very happy that I didn't refuse to this precious opportunity and that I met this amazing crew 11! Allan Morrison, Crew Engineer My time at the Hab has been spent working on the living machine in the Greenhab, performing general repairs and going on EVA to the exotic places surrounding the Hab. The living machine has presented quite a challenge getting it into a state where water could be reliably recycled with minimal maintenance. I am proud to say that with the help of several Crew 11 personnel the system is now performing well and the water quality appears to be improving. The major challenge affecting future crews will be returning the plant life in the living machine to health. Improved water quality will greatly assist this endeavor. EVAs were a highlight of my rotation and I learned a great deal about the geology of the area and the biology of extremophiles. Additionally I gained an appreciation for the beauty that typifies the American Southwest. I have been greatly honored to serve with a diverse crew of dedicated and talented people. Crew 12 will be commanded by Tony Muscatello, starts January 19, 2003, and run for 2 weeks. To find out more about the Mars Society, visit our web site at www.marssociety.org or contact info@marssociety.org. ________________________________________________________________________ PATIENT SIMULATOR WILL ENHANCE TRAINING FOR MEDICAL EMERGENCIES IN SPACE NSBRI release 17 January 2003 A lifelike mannequin will be teaching astronauts, flight surgeons and other mission personnel how to effectively manage medical emergencies in space. "This patient simulator is no dummy. It breathes, has a heartbeat, pupils that react to light and medications, a pulse that can be felt at five locations, and lung sounds," said Dr. Hal Doerr, head of the Medical Operational Support Team, a joint project of the National Space Biomedical Research Institute (NSBRI), NASA Johnson Space Center and its support contractor, Wyle Laboratories. "About 200 parameters can be changed, so we can create any type of patient and then simulate medical events that could happen." As mission lengths grow, the possibilities for medical problems in space increase. To expand the training of crew medical officers, NASA tasked the NSBRI with designing realistic training scenarios for astronauts and ground personnel involved in mission operations. "This simulator will give us an extremely realistic setting to validate and integrate medical procedures and medical equipment," said Dr. Jim Logan, MOST project administrator from NASA's Medical Informatics and Health Care Systems Office. "The project also links the medical and operations sides of a mission. In the event of a medical emergency, all parts of the mission team--crew, flight surgeons, biomedical engineers and flight operations--need to be ready to react at a moment's notice." The patient simulator is linked to a sophisticated computer, designed along the lines of a flight simulator, that controls the "patient's" reactions and can be programmed to mimic various situations that could occur. For a session on allergic reactions to medications, participants will face a wheezing simulator with a rapid pulse and swollen tongue. In some scenarios, the simulator will be programmed to talk. Doerr's group is ensuring that the simulated patient represents a potential astronaut by gathering data on the current astronaut pool. Physiologic changes that occur in space as a mission progresses also are programmed into the computer, so that realistic space scenarios can be created. "We're developing programmed scenarios for possible emergencies, such as crush trauma, inhalation burn, allergic reactions, decompression sickness, eye injury, respiratory distress, or myocardial infarction," said Doerr, director of the Houston Center for Advanced Patient Simulation at Baylor College of Medicine. "Each scenario looks at how the injury or illness can be treated with the equipment on board and for how long." NSBRI researchers, who study the health problems associated with long- term space flight, will participate in planning for the different medical contingencies. Once the scenarios are complete, Doerr says training will be most effective if it occurs in a room that mimics the size, look and sounds of areas available for medical care on the International Space Station. "When teaching, you must be able to make the participants suspend disbelief. It is hard to think clearly in a medical emergency. We're trying to create enough stress to make it realistic, so that they will fail," he said. "Once they see how difficult it can be, we explain why they failed, work through the problems and do it until they succeed." Doerr, who trains anesthesiology residents and firefighters on simulators, says this type of training will give astronauts the tools to work through an emergency medical situation more effectively. "The practice sessions teach critical thinking and critical communications. They learn how to communicate clearly to ground crews and each other during medical emergencies," Doerr said. "Crews will be prepared to provide the best in-flight medical care possible." The NSBRI, funded by NASA, is a consortium of institutions studying the health risks related to long-duration space flight. The Institute's 97 research and education projects take place at 75 institutions in 22 states involving 269 investigators. Contact: Kathy Major Phone: 713-798-5893 E-mail: major@bcm.tmc.edu Read the original release at http://www.nsbri.org/NewsPublicOut/Release.epl?r=40. An additional article on this subject is available at http://www.spacedaily.com/news/spacemedicine-03d.html. ________________________________________________________________________ COMPLEX LIFE, BY JOVE! By Leslie Mullen From Astrobiology Magazine 20 January 2003 One of the tenets of astrology is that the positions of the planets affect us. For instance, the position of the planet Jupiter in your chart is supposed to indicate good luck for a certain aspect of your life. In an eerie echo of astrology, some scientists are now saying that the position of Jupiter in our solar system was very good luck for life on Earth. Jupiter is about 5 astronomical units (AU) away from the Sun--far enough away from Earth to not have interfered with the development of our planet, and yet close enough to gravitationally deflect asteroids and comets, limiting the number of dangerous impacts. Impacts by asteroids and comets can create cataclysmic events that destroy life--witness the demise of the dinosaurs 65 million years ago, widely believed to have been brought about by a "killer" asteroid impact. Without Jupiter, instead of being hit with a killer asteroid every hundred million years or so, we'd get one every 10,000 years. This reduction in impacts enabled the Earth to develop both simple and complex forms of life. But gas giant planets like Jupiter don't always help in the development of complex life. Consider, for instance, that while Jupiter deflects many asteroids away from Earth, it also is responsible for most of the asteroids in the first place. When planetesimals were clumping together to form the terrestrial planets, the gravitational influence of Jupiter prevented a fifth planet from forming. Instead, today there is the asteroid belt that lies between Mars and Jupiter--a sad echo of the planet-that-never-was. "Only a small fraction of the original material was left behind to become the asteroid belt," says Alan Boss of the Carnegie Institution of Washington. He says that Jupiter excited this material to high orbital eccentricities, causing much of it to collide with the Sun and the growing terrestrial planets. "Jupiter does not prevent asteroid impacts on the Earth--it causes them," says Boss. "Asteroids can still be kicked out of their orbits and sent on paths that intersect the terrestrial planets." Mars also was affected by Jupiter's gravity during the early formative years. Mars is only half the size and one-tenth the mass of Earth, prevented by Jupiter from accumulating enough mass to become an Earth- like world capable of sustaining complex life. The lower mass of Mars, in combination with its low magnetism, prevented the planet from retaining an atmosphere--a vital necessity for life to exist and thrive. If Jupiter were a little more massive, or if it was closer to the Sun, the Earth might have suffered the same fate as Mars. If Jupiter were close enough to the Sun to reside in the habitable zone--0.8 AU to 1.7 AU for our solar system, or roughly from the orbit of Venus to the orbit of Mars--then the Earth and the other terrestrial planets would never have formed at all. Jupiter's gravitational influence would have prevented rocky debris from coalescing into planets. The inner solar system instead would have become a barren asteroid belt. "Habitable zones tend to be only a few AU in width, so if there is a Jupiter-mass planet inside the habitable zone, it is highly unlikely that another planet of any mass could form or exist so close by," says Boss. "Instead, the only hope for habitability in such systems would be on moons orbiting the Jupiter-mass planet." Could it be that a solar system devoid of gas giants might have the best chance for developing life? If gas giants like Jupiter and Saturn had never formed in our solar system, three Earth-like planets might have developed instead of just one. Lacking the gas giants, Uranus and Neptune-like icy planets likely would have formed in the Jupiter-Saturn region. This system would have been relatively asteroid-free, since most of the rocky debris in the early solar system would've coalesced into planets. But a Jupiter-free solar system would still have to contend with comets- -small bodies of water ice that, in our solar system, come from places like the Kuiper Belt and the Oort cloud. Comet impacts can be as disastrous to life as asteroid impacts. "In systems without asteroid belts, impactors come from the comet belts," says Donald Brownlee, an astronomer at the University of Washington in Seattle. "There is evidence that most stars form distant comet belts around them." George Wetherill of the Carnegie Institution of Washington has suggested that without Jupiter and Saturn, there would be many more comets in the Kuiper Belt. These comets would wander into the inner solar system so frequently that the Earth would be struck by a major comet impact every 100,000 years. Despite the devastation caused by asteroid and comet impacts, a solar system free of these bodies may not be the best thing for the evolution of life. For one thing, comets may be necessary for life to emerge on terrestrial planets. It is thought that comets act as delivery systems for organic material and water, elements that were necessary for the origin and development of life on Earth. According to Brownlee, Jupiter's scattering of cometary debris probably delivered most of our oceans. Although asteroid and comet impacts can destroy life, they also set the stage for new evolutionary life forms to emerge. By clearing a planet of the more dominant organisms, other life forms can move to fill in the recently vacated ecological niches. "If Jupiter was not there, or if it was smaller or further away, then there might not be an asteroid belt and thus no asteroid impacts," says Brownlee, "This can be good or bad depending on the situation. The dinosaurs were certainly not fans of the asteroids, but then they might not ever have evolved without the asteroids." The evolution of complex life on Earth owes a lot to happenstance situations like asteroid or comet impacts. Not only did dinosaurs probably owe their very existence to such impacts, but so too do humans. If the asteroid impact that killed the dinosaurs had never occurred, perhaps our ancestors would not have been able to evolve beyond the small rodents that constituted the mammalian branch 65 million years ago. Jupiter planets--rare or commonplace? How often do gas giants appear in other solar systems? In our search for planets outside our solar system, all the planets discovered to date are gas giants like Jupiter and Saturn. This does not mean that all the planets to be found are gas giants, however. An inherent bias in the search method is that it can only detect very massive planets. Almost all the extrasolar planets found so far were detected with the radial velocity, or "Doppler" technique. This technique looks at how stars are affected by the gravity of an orbiting planet. Over the course of an orbit, the planet will pull at the star from different sides. Scientists measure the Doppler shift of the starlight to tell when the star is moving slightly away from us or toward us, and from this they can roughly determine the mass and orbit of the planet that causes the shift. Over 100 Jupiter-mass planets have been found to date, from a survey of over 1,000 stars--nearly all the solar-type stars within 30 parsecs. However, Jupiters that are further away from their stars take longer to complete an orbit, and therefore require longer periods of astronomical observation. These stars might harbor many more Jupiters that have not yet been detected. Several extrasolar giants are extremely close to their stars, and many scientists believe, due to the conditions necessary for gaseous planet formation, that they must have formed further away from their stars and then migrated inward. Such behavior would be a death warrant for life on inner terrestrial planets like Earth, causing the planets to be flung outside of the solar system, away from the heat and light of their star. The highly elliptical orbits of many extrasolar Jupiters are thought to be caused by such orbital turf battles. Estimating the number of Jupiter-mass planets in the galaxy greatly relies on our understanding of planet formation. For a long time, it was thought that gas giants formed the same way terrestrial planets did - by the slow accretion of matter over many millions of years. However, the accretion model has a fundamental problem - how do gas giants accumulate enough gas before the gaseous disk around a young star dissipates? "(Jupiter-mass planets) are made of gas, and gas is lost very early in some solar systems due to intense ultraviolet irradiation from nearby stars," says Brownlee. "The success of Jupiter formation may vary with location and time due to the build up of heavy elements in the galaxy." Boss's disk instability model suggests a different manner of gas giant formation. In his model, the disk of gas and dust that swirl around a young star develop points of instability. These disturbed areas become gravitational wells, accumulating more and more matter until they form the gas giant planets. A recent computer model by Lucio Mayer and Thomas Quinn of the University of Washington, which was based on Boss's disk instability model, found that gas giants like Jupiter can form in only 1,000 years. Their computer simulation produced planets 2 to 12 Jupiter masses, with elongated orbits rather than the more circular orbits of the planets in our own solar system. "If the disk instability mechanism can work, then most planetary systems should have gas giant planets," says Boss. "However, if core accretion is the mechanism that forms gas giants, then most planetary systems may only have failed cores that grew too slowly to accrete enough gas to become gas giants. In other words, they would be full of ice giants like Neptune instead. Only observations will prove which is right." What's next? Understanding the role that Jupiter plays in our own solar system can help astronomers narrow their search for habitable planets around other stars. While current planet search techniques are limited to the detection of very massive planets, finding a planet similar to Jupiter in mass and orbital distance might indicate places where Earth-like planets could be found. After 15 years of observations, an extrasolar planet with an orbital distance similar to Jupiter's was detected in 2002. This planet, orbiting the star 55 Cancri in the constellation Cancer, orbits at approximately 5 AU. However, the planet has a mass about 4 times that of Jupiter, and this larger mass may affect the inner solar system in ways our own Jupiter does not. In addition, this solar system contains two other Jupiter-mass planets in tight orbits around their star: one at 0.115 AU, the other at 0.241 AU. These inner gas giants suggest there probably aren't any terrestrial planets within the star's habitable zone. Still, scientists are optimistic about finding other Jupiter-mass planets at similar orbital distances in the near feature. Such solar systems will be prime candidates for NASA's Terrestrial Planet Finder, a space-born telescope designed to take visual images of Earth-mass planets. The Terrestrial Planet Finder is due to be launched sometime between 2012 and 2015. Read the original article at http://www.astrobio.net/news/article359.html. ________________________________________________________________________ NEW ADDITIONS TO THE ASTROBIOLOGY INDEX By David J. Thomas http://www.lyon.edu/webdata/users/dthomas/astrobiology/astrobiology.html 20 January 2003 Astrobiology, exobiology and terraformation articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_articles1. html L. David, 2003. Mars rover planners in time crunch to prepare spacecraft, select landing sites. Space.com. ESA, 2003. Vital signs of life on distant worlds. Spaceflight Now. NASA Jet Propulsion Laboratory, 2003. Mars and the final four. SpaceDaily. Terrestrial extreme environments articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_articles2. html S. Graham, 2003. Snow algae absorb greenhouse gas. Scientific American. Human space exploration and microgravity effects articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_articles3. html Agence France-Presse, 2003. China plans first manned space launch in October. SpaceDaily. Agence France-Presse, 2003. China reaches for the stars with ambitious space plans. SpaceDaily. Earle Holland, 2003. Moss in space project to test how plants grow up. SpaceDaily. NASA Ames Research Center, 2003. Shuttle mission will focus on fundamental biology research. SpaceDaily. National Space Biomedical Research Institute, 2003. Patient simulator will enhance training for medical emergencies. SpaceDaily. T. Phillips, 2003. Science that can't be done on Earth. NASA Science News. Evolutionary biology and chemistry articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_articles5. html Agence France-Presse, 2003. Warning: man will disappear... in 500 million years. SpaceDaily. L. Mullen, 2003. Complex life, by Jove! Astrobiology Magazine. Pennsylvania State University, 2003. Dinosaurs experienced climate changes before K-T collision. SpaceDaily. University of Washington, 2003. End of the world has already begun. SpaceDaily. Planetary protection articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_articles6. html NASA Goddard Spaceflight Center, 2003. Earth likely spared from one form of cosmic doom. SpaceDaily. ________________________________________________________________________ CASSINI SIGNIFICANT EVENTS NASA/JPL release 9-15 January 2003 The most recent spacecraft telemetry was acquired from the Madrid tracking station on Tuesday, January 14. 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/operations/present-position.cfm. On-board activities this week included clearing of the ACS high water marks, Radio and Plasma Wave (RPWS) High Frequency Receiver calibrations, conclusion of Gravitational Wave Experiment #2 (GWE), return to normal cruise science, start of Cosmic Dust Analyzer Saturn dust stream observations, and uplink of Visual and Infrared Mapping Spectrometer (VIMS) flight software version 6.1. VIMS team members have prepared a mini-sequence to load and exercise the new FSW during its Fomalhaut observation activity on DOY 022. A set of Solid State Recorder (SSR) pointer reset commands caused the playback and record pointers to occupy the same location. This caused the SSR to stop recording and playing back science data, and the Command and Data Subsystem to mark SSR-B as "sick". A command file was built to reconfigure the SSR and sent to the spacecraft, which restored normal SSR operations and status. The six-week GWE #2 ended Tuesday morning, January 14. Most activities at the DSN stations were normal during the last week, although there were short periods of antenna pointing problems or lost lock, with the resultant minor gaps in uplink and downlink data. During the final pass of GWE #2, commands executed on board the spacecraft to turn off the Ka- band Exciter and Ka-band Traveling Wave Tube Amplifier. The Ka-band Translator remains on. The Radio Science Team and the Instrument Operations-Radio Science Subsystem operations team have expressed appreciation for the assistance they received from those on the Cassini Project, JPL Divisions, and the Deep Space Network who contributed to the success of GWE. The Command and Data Subsystem (CDS) Team began an end-to-end system mode test of their procedures for the uplink and checkout of the Version 9 flight software. The test will complete next week. The Spacecraft Operations Office successfully completed the first of a series of Probe Relay Operational Verification Tests to test a portion of ground operations during the probe mission. The preliminary input products for tour sequences S15/S16 were delivered last week and error reports were created and delivered to the teams. The official port 1 delivery occurs next week. A Project Briefing for the C37 cruise sequence was held this week. The Project approved this integrated plan for implementation. 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. ________________________________________________________________________ INTERNATIONAL SPACE STATION SCIENCE OPERATIONS STATUS REPORT NASA/MSFC release 03-009 16 January 2003 With the International Space Station crew's attention on its spacewalk on Wednesday, the focus of research activity was on human lung function in space and in the low-pressure environment of the spacesuits. Spacewalks are key data collection opportunities for the Pulmonary Function in Flight experiment (PuFF) science team. The principal investigator for this research is Dr. John West, of the University of California, San Diego. The crewmembers last week performed the PuFF lung function tests, which served as both their regular monthly test and as a pre-spacewalk test for astronauts Ken Bowersox and Don Pettit. They were scheduled to repeat the PuFF tests today (Thursday) for comparison to the pre-spacewalk data. The PuFF experiment consists of five lung function tests. Although numerous safety measures are in place to prevent this, spacewalkers face the risk of nitrogen bubble formation in their blood similar to the threat of decompression sickness faced by scuba divers. Symptoms in more serious cases include headaches, memory loss and blurred vision. The human body normally is exposed to 14.7 pounds per square inch (1.034 kilograms per square centimeter) of pressure at sea level. A spacesuit provides only 4.3 pounds per square inch (0.302 kilograms per square centimeter) to make movement in the pressurized suit less difficult. Additionally, little is known about how the lungs can be affected by long-term exposure to microgravity--the near- weightlessness of space. PuFF measures changes in the evenness of gas exchange in the lungs and monitors changes in respiratory muscle strength. Unevenness of gas exchange is a hallmark of virtually every pulmonary disease, and gas exchange can be temporarily disrupted by the filtration by the lungs of nitrogen bubbles in the bloodstream. Changes in respiratory muscle strength may result from long periods in the absence of gravity. Also during the spacewalk, Pettit was asked to photograph the Materials International Space Station Experiment (MISSE), located on the outside of the Station. Deployed in August 2001, it is exposing hundreds of samples--ranging from lubricants to solar cell materials - to the punishing effects of the Sun, temperature extremes, radiation, and hard vacuum of space. By examining how the specimens fare in the harsh environment of space, researchers seek new insight into developing materials for future spacecraft, as well as making materials last longer on Earth. Looking ahead to Saturday, Commander Ken Bowersox is scheduled to deactivate the Zeolite Crystal Growth (ZCG) experiment, to end this experiment's 15 day processing period--the second experiment run of Expedition Six. The Zeolite experiment has been following an automated processing routine. The goal of this experiment, sponsored by the Center for Advanced Microgravity Materials Processing at Northeastern University, Boston, MA, is to grow larger, more perfect zeolites for study on Earth. Zeolites are used in many manufacturing processes, including petroleum refining. Improving zeolites could make gasoline production more efficient or lead to ways of storing clean-burning hydrogen for fuel. Crew Earth Observation crew photography targets for today include the coastline of Lake Victoria in Kenya; Nairobi, Kenya; Dar es Salaam, Tanzania's capital city; air quality over industrialized Southeast Africa; Caracas, Venezuela; Brasilia, Brazil, the Sabancaya landslide in Peru; Patagonian Glaciers in South America; and the Pearl, Hermes, Lisianski, Laysan, and Howland Island reefs in the Pacific for a global mapping projects. On January 28, the crew and ground controllers are scheduled to begin operations with the Earth Knowledge Acquired by Middle School Students (EarthKAM) experiment for Expedition Six. EarthKAM is a NASA education program that enables thousands of students to photograph and examine Earth from a space crew's perspective. Using the Internet, the students control a special digital camera mounted onboard the International Space Station. This enables them to photograph the Earth's coastlines, mountain ranges and other geographic items of interest from the unique vantage point of space. The team at EarthKAM then posts these photographs on the Internet for the public and participating classrooms around the world to view. As part of an effort to make payload operations smoother and trouble- free, the Payload Operations Center will be uplinking some software upgrades to the Destiny laboratory's EXPRESS Racks over the next week. EXPRESS racks supply power, cooling, fluids and other utilities to science experiments housed inside. Rack 5 will be upgraded on the January 17. Rack 1 will be upgraded on January 20. Rack 4 will be upgraded on January 24. Rack 3 will be upgraded on January 27. Rack 2 will be upgraded on January 30. 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 NASA/MSFC, Huntsville, AL Phone: 256-544-0034 ________________________________________________________________________ MARS ODYSSEY THEMIS IMAGES NASA/JPL/ASU release 13-17 January 2003 IR view of lava flows (Released 13 January 2003 http://themis.la.asu.edu/zoom-20030113A.html Impact Crater (Released 14 January 2003) http://themis.la.asu.edu/zoom-20030114a.html Southern Sand Dunes (Released 15 January 2003) http://themis.la.asu.edu/zoom-20030115a.html Ridges swimming in a sea of dust (Released 16 January 2003) http://themis.la.asu.edu/zoom-20030116a.html Evidence of flow? (Released 17 January 2003) http://themis.la.asu.edu/zoom-20030117a.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, DC. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen 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 17 January 2003 This past week, the Stardust flight team had two periods of communication with the spacecraft courtesy of the antennas of JPL's Deep Space Network. The telemetry relayed during this interval indicated the spacecraft is healthy and all subsystems were running normally. During the second period of communications the Stardust team successfully powered up the spacecraft's Comet and Interstellar Dust Analyzer. This instrument is a mass spectrometer that will be used to study the chemical composition of individual particulates in the comet's coma during Stardust's encounter with Comet Wild-2 next year. 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 10, Number 3.