MARSBUGS: The Electronic Astrobiology Newsletter Volume 10, Number 7, 17 February 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) SATELLITE PHOTOGRAPHS REVEAL ANCIENT ROAD SYSTEM University of Chicago release 2) RE-THINKING NASA'S MANNED SPACE PROGRAM By Norman H. Sleep 3) CARNEGIE MELLON SCIENTIST RECEIVES NASA AWARD TO DEVELOP PROBES TO DETECT LIFE ON MARS Carnegie Mellon press release 4) NASA'S ASTROBIOLOGY INSTITUTE GENERAL MEETING BEGINS By Leonard David 5) LIFE ZONE ON VENUS POSSIBLE By Leonard David 6) ASTROBIOLOGISTS SAY PROMETHEUS JUPITER MISSION SHOULD HAVE LANDING CRAFT By Leonard David 7) PLANETARY DEFENSE CONFERENCE: PROTECTING EARTH FROM ASTEROIDS AIAA conference announcement 8) NASA STUDY SHOWS HOW WATER MAY HAVE FLOWED ON ANCIENT MARS NASA/ARC release 03-12AR 9) MURCHISON'S AMINO ACIDS: TAINTED EVIDENCE? By Anne M. Rosenthal 10) A CHALLENGE TO SPACE LEADERSHIP By John Carter McKnight 11) THE MARTIAN POLAR CAPS ARE ALMOST ENTIRELY WATER ICE, CALTECH RESEARCH SHOWS Caltech news release 12) CHINA'S MANNED SPACE MISSION STAYS ON COURSE FOR OCTOBER LAUNCH From China Daily and SpaceDaily 13) STUDIES EXAMINE EVOLUTION OF TWO WORLD-ALTERING CHEMICAL PROCESSES IN BIOSPHERE, POINT TO POSSIBLE ORIGIN Arizona State University release 14) COMMON DESERT ORGANISMS MAY HELP IN SEARCH FOR LIFE IN SPACE Arizona State University release 15) EARLY MARS: WARM ENOUGH TO MELT WATER? Pennsylvania State University release 16) NASA PRESENTS LATEST MARS ODYSSEY OBSERVATIONS NASA note n03-017 17) BUGS FROM THE DEEP MAY BE WINDOW INTO THE ORIGINS OF LIFE--ON EARTH AND BEYOND AAAS release 18) EUROPA SURFACE MISSIONS NECESSARY STEP IN EXTRATERRESTRIAL SEARCH Arizona State University release 19) ROLL WITH THE ROVERS AND "EXPLORE MARS" FEBRUARY 19 NASA/KSC release 19-03 20) LOS ALAMOS MAKES FIRST MAP OF ICE ON MARS Los Alamos National Laboratory release 21) CHINA TO SEND MAN INTO SPACE THIS FALL, WITH SIGHTS ON MOON From Agence France-Presse and SpaceDaily 22) GREAT IMPACT DEBATE, PART II: MUCH ADO ABOUT NOTHING? Moderated by Don Yeomans 23) BEFORE COLUMBIA: A PERSONAL VIEW By Bruce Moomaw 24) ASTEROID COVER-UP PROPOSAL CAUSES NEO COMMUNITY A CREDIBILITY CRISIS By Benny Peiser 25) NEW ADDITIONS TO THE ASTROBIOLOGY INDEX By David J. Thomas 26) CONTINUING COVERAGE OF THE COLUMBIA DISASTER By David J. Thomas 27) CASSINI SIGNIFICANT EVENTS NASA/JPL release 28) INTERNATIONAL SPACE STATION SCIENCE UPDATE NASA release 03-066 29) MARS ODYSSEY THEMIS IMAGES NASA/JPL/ASU release 30) STARDUST STATUS REPORT NASA/JPL release ________________________________________________________________________ SATELLITE PHOTOGRAPHS REVEAL ANCIENT ROAD SYSTEM University of Chicago release 28 January 2003 Archaeologists at the University of Chicago's Oriental Institute have used recently declassified satellite surveillance images to show that subtle land depressions--which had gone largely unnoticed by scholars-- are actually the remnants of ancient roadways that knitted together the fabric of emerging civilizations in the ancient Near East. These 5,000- year-old roadways were important thoroughfares for agricultural exchange and other commerce in an area of Syria and Iraq. It was here that expanding local settlements were coming into contact with cultures from southern Mesopotamia as urban civilization developed in the third millennium BC, according to Tony Wilkinson, Research Associate at the institute, and Jason Ur, a researcher at the institute. The ancient roads went out of service when better routes emerged late in the first millennium BC. Because the old roads were in slight depressions, they became locations where local people gathered moist clay for mud bricks. Over the years, the roadways faded and they largely escaped the attention of archaeologists. Although research by the Oriental Institute team focuses on the northern reaches of Mesopotamia, the roads probably were common throughout the region, the scholars said. The roadways were 200 to 400 feet wide and 20 to 24 inches deep. They were made by early people who herded their livestock to fields for pasture and between towns as part of the emerging economic system. Continual traffic by people, animals and vehicles hardened the surface and caused the roadway to sink into the landscape. These inter-site routes are more than connections between towns and nearby settlements, the scholars said. "When considered at a regional level, these routes emerge as segments of larger 'highways' that run from site to site on a generally east-west axis," wrote Ur in his paper, "CORONA Satellite Photography and Ancient Road Networks: A Northern Mesopotamian Case Study," to be published in the spring issue of the journal Antiquity. Previously, archaeologists had drawn straight lines between major settlements, supposing a road system connected them, but not knowing its exact location. Now, rather than connecting the dots in an abstract way, they are able to see where the roads were and how they meandered between settlements. The information also shows that the most important towns were those with the most roadways leading to them. The recent Oriental Institute work in northeastern Syria is based on two sites, Tell Brak and Tell Hamoukar, both of which emerge as communities of some importance in the third millennium BC. The satellite images show that Tell Hamoukar--the site of a continuing Oriental Institute expedition--was a more important site than scholars had previously thought. Wilkinson and Ur agree it probably was on a road system that stretched from Nineveh, in what is now northern Iraq, to possibly Aleppo in western Syria near the Mediterranean. "For the Early Bronze Age, new conclusions can be drawn about the underlying economy, which had a large role in producing this pattern of settlements and roads," Ur said. "The agricultural backbone of these towns is vividly illustrated by the abundant radial system of roads, although the interconnectedness of these systems suggests a far more integrated agricultural economy than originally recognized." High-value luxury goods, such as textiles and metals, also traveled on these routes. Now with a better picture of how communities were connected, scholars will be able to further document trade using ancient texts. [Image 1] http://www-news.uchicago.edu/releases/03/oi-corona/oi-corona-01.jpg Ancient roads, clearly visible in a CORONA satellite surveillance photograph, extends from the ancient city of Tell Hamoukar, site of Oriental Institute excavations in Syria. One road goes to the southwest and forms a fork. The road connected the ancient settlement with another several miles away. Image credit: USGS. [Image 2] http://www-news.uchicago.edu/releases/03/oi-corona/oi-corona-02.jpg Roads radiate from Tell Brak, an ancient site in Syria. The ancient roads, which are clearly seen in CORONA satellite surveillance photographs, indicate that the settlement was an important city. Image credit: USGS. [Image 3] http://www-news.uchicago.edu/releases/03/oi-corona/oi-corona-03.jpg A road, visible on CORONA satellite photography, leaves the ancient settlement of Tell Beydar in Syria, and goes through a plowed field into nearby hills. Image credit: USGS. [Image 4] http://www-news.uchicago.edu/releases/03/oi-corona/oi-corona-04.jpg CORONA satellite imagery permits archaeologists to measure the size of ancient sites with great precision because it enables measurement of uneven, irregular walls such as the site of ancient Nineveh in Iraq, across the Tigris River from modern day Mosul. Image credit: USGS. Contact: William Harms University of Chicago News Office Chicago, Illinois Phone: 773-702-8356 E-mail: w-harms@uchicago.edu ________________________________________________________________________ RE-THINKING NASA'S MANNED SPACE PROGRAM By Norman H. Sleep Stanford University release 4 February 2003 It is time to rethink the manned space program. Despite the Columbia shuttle disaster on Saturday, which took the lives of seven astronauts, NASA officials have called for the shuttle program to continue. The cry, "Let's go on to Mars," has even been heard from some quarters in NASA. What has post-Apollo manned space flight provided beyond adventure? There have been some scientific spin-offs, to be sure, but any large technical program--even a more ill thought out one, such as trying to live at the bottom of the sea--would have done that. The science contributions have been mostly targets of opportunity. For example, scientists have skillfully studied organisms in weightlessness. Extensive space sickness studies are necessary to keep the crew healthy. Yet no benefit to the 5 billion-plus people on the ground has come out of this work. No engineering application, such as making crystals or chemicals in space, has panned out. After 40 years, it is not too soon to ask for some practical results. In contrast, unmanned satellites benefit everyone on Earth. One cannot turn on a television, make a long-distance phone call or turn on the Internet without having signals go through space. Weather satellites provide minute-to-minute worldwide coverage and timely warnings, and satellites image the ground motion around earthquake faults and volcanoes. Satellites also have revolutionized astronomy. No one would think of sending up people to get in the way of these applications. It would be like having a cloak-and-dagger guy aboard a spy satellite. Yet NASA has designed numerous robotic satellites to be launched from the shuttle--including the much-vaunted Hubble Space Telescope, which was placed into orbit by astronauts aboard the shuttle Discovery in 1990. Manned space flight in Earth orbit is inefficient, somewhat dangerous but not overwhelmingly expensive. Mars space flight is another story. The cost of getting people there and back is more than a trillion dollars--yes, "trillion" with a "t." The popular and scientific interest in Mars is biology. Can we find evidence of living or fossil microbes? If not, can we catch the origin of life, frozen billions of years ago, in the act? A speck of organic dust or a live microbe would be a monumental discovery. A manned spacecraft with its life supports would risk contaminating Mars, which would likely defeat the scientific purpose of the mission. Norman H. Sleep is a professor of geophysics and, by courtesy, of geological and environmental sciences. A planetary scientist, Sleep studies the origin of the solar system and the conditions on early Earth that led to microbial life. His research has been published in Nature and other scientific journals. He was elected to the National Academy of Sciences in 1999. Relevant web URLs: * http://pangea.stanford.edu/GP/sleep.html * http://nai.arc.nasa.gov/news_stories/news_detail.cfm?ID=153 Contact: Mark Shwartz Stanford University News Service Stanford, California Phone: 650-723-9296 E-mail: mshwartz@stanford.edu ________________________________________________________________________ CARNEGIE MELLON SCIENTIST RECEIVES NASA AWARD TO DEVELOP PROBES TO DETECT LIFE ON MARS Carnegie Mellon press release 10 February 2003 Carnegie Mellon University scientist Professor Alan Waggoner has received a three-year $900,000 award from NASA to develop fluorescent- dye-based systems to be used in remote operations to detect life on Mars and in other hostile or distant environments. As part of the grant, Waggoner's team will develop new fluorescent dyes that bind to the common building blocks of life--DNA, lipids, carbohydrates and proteins. The grant also provides funds to develop an optical system that can spray these fluorescent dyes on a region of soil to detect life forms in the environment. This system is expected to be completed within several years. The Waggoner team is collaborating with researchers at Carnegie Mellon's Robotics Institute; the final life detection system should be versatile enough to couple with different types of rovers used in planetary expeditions. The scope of the grant includes developing dyes and testing their feasibility in local environments, as well as areas hostile to life, such as the Atacama Desert in northern Chile, where relatively few pockets of life persist. Given its Mars-like terrain, the Atacama is a favorite laboratory testing ground for astrobiologists. "It's tremendously exciting to extend the work of our team and contribute to interplanetary searches for life," says Waggoner, who directs the Molecular Biosensor and Imaging Center (MBIC) at the Mellon College of Science. "We believe that these methods will provide the most sensitive means of detecting life with a remote device." The technology has potential beyond Mars, according to Shmuel Weinstein, project manager. "The scientific impact of our work begins on earth, with the ability to detect very low concentrations of living and dead organisms." Once developed, this system could work in circumstances such as biohazardous settings or extreme environments, where an automated, unmanned device would be ideal. Developing fluorescent markers to detect life in space for this project presents many technical challenges, according to Gregory Fisher, project imaging scientist. Fluorescent markers that bind to their targets must stand out against what could be a blinding background of natural mineral luminescence. Additionally, detecting low levels of light emitted from relatively few organisms could be difficult against reflected light that is originally emitted from the optical instrument. Just as big a challenge is creating a detection system that resembles a good epifluorescence microscope used on earth, but one with few, if any, moveable parts. The completed system will need to focus using a camera range finder (like those found in hand-held cameras), in addition to providing some additional processing of its own camera images. "Other testing methods require considerably more sampling or are less sensitive than what we propose. We don't know of other remote methods capable both of detecting low levels of microorganisms and visualizing high levels incorporated as biofilms or colonies," adds Fisher. Additionally, notes Lauren Ernst, project chemist, martian life forms may contain different structural components than those found on earth. "We want our reagents to visualize any form of life that might be present. We will define fluorescent probes to detect the smallest amounts of DNA, lipids, carbohydrates and proteins." For example, Ernst will design fluorescent tags to the materials containing peptide bonds, a signature feature of proteins. Other tags will target a variety of sugars that comprise carbohydrates. Moreover, these tags will not be specific for left- or right-handed structures. Such "handedness," or chirality, characterizes proteins and other compounds on earth, but martian life could exhibit opposite chirality from our own. Other members of Waggoner's team who will be performing critical research as part of this grant include Christoffer Lagerholm and Byron Ballou. The fluorescent marker technology proposed is based on the extensive expertise of the MBIC at Carnegie Mellon. Established 17 years ago with a multimillion-dollar grant from the National Science Foundation, MBIC combines research on molecular and cellular sensors along with research in imaging and computation to understand biological function. The Waggoner team is world renowned for developing widely commercialized cyanine dye fluorescent labeling reagents that have played a significant role in the human genome project and are the main dyes used to analyze gene activity in the regulation of cells and tissues. For more information about the grant or MBIC, please contact Lauren Ward at 412-268-7761 or wardle@andrew.cmu.edu. For information about interplanetary research under way at the Robotics Institute, please contact Anne Watzman at 412-268-3830 or aw16@andrew.cmu.edu. Contact: Eric Sloss Phone: 412-268-5765 Read the original news release at http://www.cmu.edu/PR/releases03/030210_mars.html. An additional article on this subject is available at http://www.spacedaily.com/news/mars-robot-03a.html. ________________________________________________________________________ NASA'S ASTROBIOLOGY INSTITUTE GENERAL MEETING BEGINS By Leonard David From Space.com 10 February 2003 Scientists here are grappling with the search for life, not only in space, but right here on Earth. Nearly 600 scientists from around the world have gathered here to report on the burgeoning field of astrobiology--the study of life on our home planet and elsewhere. New studies were unveiled at the opening day of NASA's Astrobiology Institute General Meeting, held here this week at Arizona State University. The research provides evidence that some of the most important evolutionary events in Earth's history didn't just create new organisms--they created new fundamental biochemical processes. Moreover, those biochemical processes evolved from other biochemical processes. Read the full article at http://www.space.com/scienceastronomy/astrobio_AZ1_030210.html. ________________________________________________________________________ LIFE ZONE ON VENUS POSSIBLE By Leonard David 11 February 2003 Microbes may be riding high in the atmosphere of Earth's sister planet, Venus. A research team is proposing that a future mission to that cloud-covered world could scoop up the living proof, then transport the specimens for detailed inspection onboard the International Space Station. The speculative work was highlighted during the NASA Astrobiology Institute General Meeting 2003, being held here February 10-12. Upwards of 600 scientists from around the globe are presenting new findings in understanding the evolution of life on Earth and elsewhere in the Universe. Read the full story at http://www.space.com/scienceastronomy/astrobio_venus_030211.html. ________________________________________________________________________ ASTROBIOLOGISTS SAY PROMETHEUS JUPITER MISSION SHOULD HAVE LANDING CRAFT By Leonard David 11 February 2003 Scientists here at the NASA Astrobiology Institute General Meeting 2003 this week have welcomed the news that NASA's Project Prometheus--work on nuclear electric propulsion--has picked as a flagship mission the exploration of the icy moons of Jupiter. To be flown within a decade, a nuclear-powered probe would search for evidence of global subsurface oceans on Jupiter's three icy Galilean moons, Europa, Ganymede, and Callisto. These oceans may harbor organic material, with the spacecraft moving from moon to moon, training an array of equipment on each world. Scientists have long thought Europa is a prime candidate for life. It's one of the few places in the solar system where liquid water may be found. That being the case, a new phase of exploring the moon should include surface landers, contend astrobiologists meeting here. Read the full story at http://www.space.com/businesstechnology/technology/astrobio_prometheus_0 30211.html. ________________________________________________________________________ PLANETARY DEFENSE CONFERENCE: PROTECTING EARTH FROM ASTEROIDS AIAA conference announcement 11 February 2003 February 23-26 (Monday - Thursday), 2004 Hyatt Orange County, Garden Grove, California The Planetary Defense Conference, sponsored by the American Institute of Aeronautics and Astronautics and The Aerospace Corporation, will address key technical issues associated with defending Earth from approaching near Earth objects (comets and asteroids). The threat will be approached from three warning levels: short-term (less than ten years warning); medium-term (ten to 30 years warning); and long-term (more than 30 years warning). The conference intends to define several possible threat scenarios and develop potential responses to each. Focused conference topics include: * examining current and future detection capabilities and options * considering current and future techniques, hardware and systems that are available to mitigate threats * discussing national and international policy implications of mounting a planetary defense effort * developing recommendations for future work, strategies, and policies * developing recommendations for demonstrations, experiments, and near- term activities * discussing public safety and disaster preparedness implications of possible asteroid or comet impacts. Technical paper abstracts are currently being accepted electronically through AIAA's web site at http://www.aiaa.org. Read the original conference announcement at http://www.aero.org/conferences/planetdef/. ________________________________________________________________________ NASA STUDY SHOWS HOW WATER MAY HAVE FLOWED ON ANCIENT MARS NASA/ARC release 03-12AR 12 February 2003 NASA scientists have discovered how an intricate martian network of streams, rivers and lakes may have carried water across Mars. Using new three-dimensional data from the Mars Global Surveyor spacecraft and a powerful state-of-the-art computer code that 'models' overland water flow, scientists visualized the complex flow of martian water. These data, acquired by the laser altimeter on board the spacecraft, provided highly accurate, three-dimensional topographic views of Mars. "We've known for some time that Mars contains lakebed and stream-like surface features, and that many of these stream features run into depressions, then end abruptly," said Marc G. Kramer, a visiting National Research Council scientist at NASA Ames Research Center in California's Silicon Valley. Kramer is principal author of a peer- reviewed news article about the study that recently appeared in EOS, a weekly American Geophysical Union publication. "A new aspect of this study shows how these two features link to one another as a single, integrated water network that may have existed on Mars at some time in the past," he said. The study spans portions of the equatorial region on the martian highlands that extend from the northern mid latitudes to the southern mid latitudes. Kramer's co-authors are Christopher Potter, David Des Marais and David Peterson, all from NASA Ames. Scientists have long been puzzled as to why some ancient river-like features on the red planet do not seem to connect to one another and often lack smaller stream features. "If you look at a photograph of the surface of Mars, the river features begin and end abruptly, and often lack small-scale features," Kramer said. "Many scientists have argued that these features were formed from localized groundwater seeping to the surface. Others have argued that these features formed from precipitation during a time when Mars may have had a thicker atmosphere." "What we found in this study, is that many of these apparently fragmented river features may have connected or flowed into depressions that resemble ancient lake beds," Kramer explained. "Some of the larger depressions are comparable in size to the Great Lakes in North America in terms of surface area." In addition, some of the larger depressions of the main channel system are comparable in volume to Lake Erie, the smallest of the Great Lakes in North America, Kramer added. Large lakes and rivers on Mars once may have formed water systems that included many streams and smaller lakes, according to the scientists. The study found that the areas near the Great Lakes on Earth bear a strong resemblance to features on Mars. Although the areas appear to be similar, they formed in different ways, according to Kramer. The study of surface depressions in conjunction with river features, provides a more complete picture of a surface water network that may have existed on what must have been a warmer early Mars, according to Potter. The researchers excluded fresh impact crater areas during the analysis in order to study older drainage patterns. "The larger shallow depressions in the main channel system often contain multiple, highly eroded craters and show evidence of stream features in the extensive upland regions draining into them," Kramer said. These depressions become increasingly shallow downstream, suggesting that increased sedimentation may have been deposited by water or ice that once may have flowed through them, according to the scientists. "Still unclear is how long such a water system may have persisted, and under exactly what climate conditions," he said. "The answers to these questions may lie in further examination of the sediments that have accumulated across the depressions of the surface water network." "New instruments on the Mars Odyssey spacecraft, including the Thermal Emission Imaging System (THEMIS) instrument, address these questions," Kramer said. THEMIS infrared and visible light images have revealed a diversity of surface types and features. Nighttime temperature images show complex patterns of rock layers, rocky debris, sand and dust produced by impact cratering, wind erosion, volcanism and deposition. "The data coming out of the Mars Global Surveyor and Mars Odyssey Mission are quite revealing," Kramer said. "We were able to study the planet in ways that were previously not possible." "With an abundance of ice recently detected just below the surface of Mars, the possibility that life has existed or still may exist may hinge on its past climate and the duration of surface water flows," Potter said. "Was Mars ever a warm and wet planet, or has it always been cold and dry?" he asked. The Jet Propulsion Laboratory, Pasadena, CA, manages the Mars Global Surveyor and Mars Odyssey missions. The NASA Astrobiology Institute, based at NASA Ames, funded the study that resulted in the peer-reviewed article. Publication size images are available at http://amesnews.arc.nasa.gov/releases/2003/03images/marslake/marslakes.h tml. Contact: John Bluck NASA Ames Research Center, Moffett Field, CA Phone: 650-604-5026 or -9000 E-mail: jbluck@mail.arc.nasa.gov Additional articles on this subject are available at: http://www.spacedaily.com/news/mars-water-science-03b.html http://www.space.com/scienceastronomy/astrobio_mars_030212.html ________________________________________________________________________ MURCHISON'S AMINO ACIDS: TAINTED EVIDENCE? By Anne M. Rosenthal From Astrobiology Magazine 12 February 2003 Could meteorite bombardment in Earth's early history have delivered the chemical building blocks essential for life? One way to answer that question is to study the chemistry of meteorites from observed falls, says University of Oklahoma geochemist Michael H. Engel. Quickly collected, such meteorites are exposed only minimally to weathering processes and contamination by earthly materials. Over the last two centuries, stones have been collected from about 35 observed falls of carbonaceous chondrites. These meteorites contain materials coalesced from dense molecular clouds during or prior to the formation of the solar system. They are of special interest because, like life on Earth, they contain organic or carbon-based compounds. But chemical studies of these meteorites have often been challenged as unreliable by scientists claiming that contamination has occurred through exposure, storage, or handling. Over time, says Jeff Bada, of the Scripps Institute of Oceanography, even carefully stored meteorites gradually become contaminated. If organic compounds such as amino acids from Earth's biosphere have penetrated meteorite samples, they would no longer be representative of early solar system chemistry, nor could they provide evidence of an extraterrestrial source for the components of Earth's first life. But figuring out whether or not a meteorite has been contaminated has proven to be a thorny problem. The Murchison meteorite, which fell about 100 kilometers (about 60 miles) north of Melbourne, Australia, in 1969, is one of the world's most closely studied carbonaceous chondrites. According to Engel, several lines of evidence indicate that the interior portions of well- preserved fragments from Murchison are pristine. Engel points to the array of amino acids Murchison contains and to isotope studies to bolster his position. Other scientists are equally convinced that the evidence proves the opposite: that Murchison is now thoroughly contaminated by terrestrial organic material. Indeed, the results of various experiments performed on Murchison are a bit of a head- scratcher--and a good window into how science works when data are ambiguous. Tallying amino acids Over the past three decades, Murchison studies, particularly those of John Cronin and Sandra Pizzarello of Arizona State University (ASU), showed that the meteorite contains a fascinating assemblage of amino acids. More than fifty of the amino acids found in Murchison are not present on Earth. Murchison also contains many of the protein amino acids incorporated into Earth's living systems--but it doesn't include all of them. The portfolio of amino acids in Murchison provides evidence that it has not been contaminated, says Engel. He and Stephen Macko of the University of Virginia, Charlottesville, maintain that if amino acids from Earth had found their way into the interior of Murchison samples, scientists, including Engel and Macko, would find the complete spectrum of amino acids present on Earth, not just some of them. Bada and others counter that the missing amino acids were probably there, but that Engel and Macko simply didn't detect them, perhaps because their equipment wasn't sufficiently sensitive. Mirror image There are also other differences between the amino acids in Murchison and those typically found on Earth, differences that pertain to the issue of contamination. One of these differences has to do with the chirality, or handedness, of the molecules. To understand the concept of chirality, Engel suggests, bring your hands together with palms facing each other, and note that your thumbs and fingers line up. But if instead you place the palm of one hand atop the back of the other, your hands no longer coincide. That's because your hands are mirror images of each other. When a molecule comes in two mirror-image forms, it is termed chiral. The majority of amino acids are chiral molecules. A curious aspect of Earth's life forms is that they contain (with few exceptions) only left-handed amino acids. In contrast, when scientists synthesize amino acids from nonchiral precursors, the result is always a "racemic" mixture--equal numbers of right- and left-handed forms. Scientists have been unable to perform any experiment that, when starting with conditions believed to emulate those of early Earth, results in a near-total dominance of left-handed amino acids, says George Cody, a geochemist at the Carnegie Institute of Washington. Scientists are especially interested in amino acids that are the building blocks for proteins, which serve as both structural components and enzymes in terrestrial life forms. Engel and colleagues published chemical analyses of some of the protein amino acids from Murchison in Nature in 1982 and 1990. They found that Murchison had neither the complete dominance of left-handed amino acids found on Earth nor the racemic mixture expected, on the basis of laboratory experiments, for materials formed in space. Instead, their results showed a moderate to strong predominance of left- handed forms. Engel and colleagues interpreted their results as showing that the extraterrestrial material in Murchison was not racemic, but had a different mixture of the left- and right-handed forms than materials found on Earth. They did not see their findings as evidence of contamination, even though their interpretation was at odds with the first analysis of Murchison amino acids, published in 1971 by Keith Kvenvolden (then of NASA Ames Research Center--Kvenvolden is now at the US Geological Survey) and his NASA colleagues. The results of Kvenvolden, et al., had shown a left-handed excess, but only a small one. Therefore, Kvenvolden and colleagues had interpreted their results as indicative that the amino acids in Murchison were racemic, as anticipated--if they were extraterrestrial. They concluded that the most likely explanation was that after Murchison arrived bearing a racemic mixture, it was contaminated by amino acids from Earth. Kvenvolden points outs that it's possible that impurities in the chemicals used to perform the analysis could have distorted the results. Because Engel and Macko had found a much greater left-handed excess than Kvenvolden, et. al., they had interpreted it as evidence that the extraterrestrial material in Murchison was not racemic. This interpretation was rebuffed by Bada, Kvenvolden, and others, kind of who attributed the excess to contamination, as Kvenvolden had for his own data. Circumventing contamination To skirt the issue of contamination, Cronin and Pizzarello decided to study four of the Murchison amino acids that are not found on Earth. What Cronin and Pizzarello found was a small predominance of left-handed forms. Their conclusion: at least for some amino acids, there must have been an excess of left-handed forms indigenous to the meteorite. Earthly materials penetrating Murchison could not have influenced the percentage of left-handed forms in these non-terrestrial amino acids. Cronin and Pizzarello published their results in Science in 1997. While these results would appear to support the findings of Engel and Macko, in the same study the ASU scientists also looked at two Murchison amino acids that are present in terrestrial proteins and found them to be racemic. How did Cronin and Pizzarello explain this confusing result? The non-protein amino acids must have formed by a different process than the protein amino acids, they wrote in their report. What those processes might have been, however, have not yet been clarified. Weighing the evidence Meanwhile, Engel and Macko were conducting another set of experiments to show that the Murchison interior was pristine. This work looked at stable-isotopic signatures. Isotopes of an element are variants that have the same number of protons but different numbers of neutrons, and thus different atomic weights. Because life on Earth preferentially uses lighter isotopes of carbon and nitrogen, scientists can use isotopic signatures to distinguish terrestrial organic materials from extraterrestrial. Engel and Macko first separated amino acids extracted from Murchison into right-handed and left-handed forms, using a technique called gas chromatography. Then, with an instrument called a mass spectrometer, they determined carbon and nitrogen stable-isotope ratios separately for the left-handed and right-handed forms of the molecules. The investigators found that the stable isotope ratios were identical for the left-handed and right-handed forms. This, says Engel, indicates, that they had to have come from the same source--that is, not from Earth. If, he argues, a portion of the left-handed forms were from terrestrial organics, these forms would have exhibited a different isotopic signature than the right-handed forms. They would have contained more light carbon and nitrogen. Kvenvolden and Bada aren't convinced. The new stable-isotope evidence notwithstanding, says Kvenvolden, a left-handed excess like that found in previous research by Engel and Macko, "is inconsistent with the observations of Cronin, Pizzarello and myself for protein amino acids in the meteorite." Kvenvolden firmly believes Engel and Macko were seeing contamination. Cronin and Pizzarello suggest that Engel and Macko's most recent findings could be caused by coelution: extra, unwanted, compounds exiting from the gas chromatograph column at the same time as the left- handed amino acids. This would skew the data. Engel disputes this explanation, pointing out that work was done separately for the C and N isotopes. It would be a highly unlikely coincidence, he says, for coelution to mask a contamination signature for both C and N stable isotope ratios. Thus, Engel concludes, there are portions of Murchison that remain pristine, uncontaminated. What's next? Even if it can be demonstrated conclusively that Murchison contains amino acids with a slight left-handed excess, and that this excess is not due to contamination or experimental artifacts, would that explain the world of left-handed amino acids in which we live? Not necessarily. On the one hand, says Cody, "the only evidence of the prebiotic world is carbonaceous meteorites, and remarkably, they appear to have a slight [left-handed] enhancement." On the other hand, he points out, that this may not tell us anything about how the almost complete dominance of left-handed forms in terrestrial life got its start. According to Bada, it doesn't much matter whether the amino acids that rained down on Earth in meteorites before life began had a slight left- handed excess. Once they arrived and mixed with the environment, Bada says, commonplace chemical reactions would have erased the left-handed signature. As for contamination, only laboratory analysis designed to eliminate the possibility of coelution, preferably with carefully handled samples from fresh meteorite falls, is likely to settle the question to everyone's satisfaction. As Cody notes, "It's really difficult to be 100 percent definitive in this because there's still so may unknowns. Contamination will always be an issue." Read the original article at http://www.astrobio.net/news/article375.html. ________________________________________________________________________ A CHALLENGE TO SPACE LEADERSHIP By John Carter McKnight From SpaceDaily 12 February 2003 Advocates of real human space exploration are doomed to impotence and irrelevance. Crippled by petty infighting, slaves to personality cults, disorganized and rudderless, the space community is incapable of acting to change the American public agenda. I challenge the leadership of the space movement: prove me wrong. Organize to make a difference now. For the first time since the 1986 Challenger disaster, Congress and the White House are open to the prospect of a real transformation of space policy. Thirty years of benign neglect of NASA's status-quo drift might end. We could take the firsts substantial steps out of manned spaceflight force-in-being maintenance and into exploration. We might actually be poised to leave the cradle. Or the sleeping dragon of spacefaring may snort once or twice, shift about a bit, and return to its generation-long nap. Read the full article at http://www.spacedaily.com/news/oped-03k.html. ________________________________________________________________________ THE MARTIAN POLAR CAPS ARE ALMOST ENTIRELY WATER ICE, CALTECH RESEARCH SHOWS Caltech news release 13 February 2003 For future martian astronauts, finding a plentiful water supply may be as simple as grabbing an ice pick and getting to work. California Institute of Technology planetary scientists studying new satellite imagery think that the martian polar ice caps are made almost entirely of water ice-with just a smattering of frozen carbon dioxide, or "dry ice," at the surface. Reporting in the February 14 issue of the journal, Science, Caltech planetary science professor Andy Ingersoll and his graduate student, Shane Byrne, present evidence that the decades-old model of the polar caps being made of dry ice is in error. The model dates back to 1966, when the first Mars spacecraft determined that the martian atmosphere was largely carbon dioxide. Scientists at the time argued that the ice caps themselves were solid dry ice and that the caps regulate the atmospheric pressure by evaporation and condensation. Later observations by the Viking spacecraft showed that the north polar cap contained water ice underneath its dry ice covering, but experts continued to believe that the south polar cap was made of dry ice. However, recent high-resolution and thermal images from the Mars Global Surveyor and Mars Odyssey, respectively, show that the old model could not be accurate. The high-resolution images show flat-floored, circular pits eight meters deep and 200 to 1,000 meters in diameter at the south polar cap, and an outward growth rate of about one to three meters per year. Further, new infrared measurements from the newly arrived Mars Odyssey show that the lower material heats up, as water ice is expected to do in the martian summer, and that the polar cap is too warm to be dry ice. Based on this evidence, Byrne (the lead author) and Ingersoll conclude that the pitted layer is dry ice, but the material below, which makes up the floors of the pits and the bulk of the polar cap, is water ice. This shows that the south polar cap is actually similar to the north pole, which was determined, on the basis of Viking data, to lose its one-meter covering of dry ice each summer, exposing the water ice underneath. The new results show that the difference between the two poles is that the south pole dry-ice cover is slightly thicker-about eight meters-and does not disappear entirely during the summertime. Although the results show that future astronauts may not be obliged to haul their own water to the Red Planet, the news is paradoxically negative for the visionary plans often voiced for "terraforming" Mars in the distant future, Ingersoll says. "Mars has all these flood and river channels, so one theory is that the planet was once warm and wet," Ingersoll says, explaining that a large amount of carbon dioxide in the atmosphere is thought to be the logical way to have a "greenhouse effect" that captures enough solar energy for liquid water to exist. "If you wanted to make Mars warm and wet again, you'd need carbon dioxide, but there isn't nearly enough if the polar caps are made of water," Ingersoll adds. "Of course, terraforming Mars is wild stuff and is way in the future; but even then, there's the question of whether you'd have more than a tiny fraction of the carbon dioxide you'd need." This is because the total mass of dry ice is only a few percent of the atmosphere's mass and thus is a poor regulator of atmospheric pressure, since it gets "used up" during warmer climates. For example, when Mars's spin axis is tipped closer to its orbit plane, which is analogous to a warm interglacial period on Earth, the dry ice evaporates entirely, but the atmospheric pressure remains almost unchanged. The findings present a new scientific mystery to those who thought they had a good idea of how the atmospheres of the inner planets compared to each other. Planetary scientists have assumed that Earth, Venus, and Mars are similar in the total carbon dioxide content, with Earth having most of its carbon dioxide locked up in marine carbonates and Venus's carbon dioxide being in the atmosphere and causing the runaway greenhouse effect. By contrast, the eight-meter layer on the south polar ice cap on Mars means the planet has only a small fraction of the carbon dioxide found on Earth and Venus. The new findings further pose the question of how Mars could have been warm and wet to begin with. Working backward, one would assume that there was once a sufficient amount of carbon dioxide in the atmosphere to trap enough solar energy to warm the planet, but there's simply not enough carbon dioxide for this to clearly have been the case. "There could be other explanations," Byrne says. "It could be that Mars was a cold, wet planet; or it could be that the subterranean plumbing would allow for liquid water to be sealed off underneath the surface." In one such scenario, perhaps the water flowed underneath a layer of ice and formed the channels and other erosion features. Then, perhaps, the ice sublimated away, to be eventually redeposited at the poles. At any rate, Ingersoll and Byrne say that finding the missing carbon dioxide, or accounting for its absence, is now a major goal of Mars research. Images are available at http://www.gps.caltech.edu/~shane/swiss_press.html. Contact: Robert Tindol Phone: 626-395-3631 E-mail: tindol@caltech.edu Additional articles on this subject are available at: http://www.sciencemag.org/cgi/content/short/299/5609/1048 http://www.sciencemag.org/cgi/content/short/299/5609/1051 http://www.space.com/scienceastronomy/mars_ice_030213.html http://www.spacedaily.com/news/mars-water-science-03c.html ________________________________________________________________________ CHINA'S MANNED SPACE MISSION STAYS ON COURSE FOR OCTOBER LAUNCH From China Daily and SpaceDaily 14 February 2003 China expects to stage its first manned space flight this year, despite the recent loss of US space shuttle Columbia, a top aerospace official said Thursday in Beijing. Zhang Qingwei, president of China Aerospace Science and Technology Corp., made it clear the U.S. incident will not upset China's applecart. "China put into place its space program long ago, and it will stick to its schedule without being distracted," he told China Daily in an exclusive interview Thursday. This is the first time since the Columbia tragedy on February 1 that China's space authority has explicitly promised to forge ahead with its plan of sending astronauts into orbit. There has been no official announcement specifying when China will launch its first manned spacecraft before now. Read the full story at http://www.spacedaily.com/news/china-03g.html. ________________________________________________________________________ STUDIES EXAMINE EVOLUTION OF TWO WORLD-ALTERING CHEMICAL PROCESSES IN BIOSPHERE, POINT TO POSSIBLE ORIGIN Arizona State University release 14 February 2003 Some of the most important evolutionary events in Earth's history didn't just create new organisms--they created new fundamental biochemical processes. And where do biochemical processes come from? They evolve from other biochemical processes. Two of the most important pieces of biochemical innovation that occurred in the early biosphere--the development of photosynthesis (which made light energy available to life) and of nitrogen fixation (which made atmospheric nitrogen available to life)--may be related to each other because some of their key enzymes appear to have evolved from a common ancestor that may be part of a third, significantly different, biochemical process. "Photosynthesis was important because it gave life an enormous energy source and ultimately put oxygen in the atmosphere," said Arizona State University biochemist Robert Blankenship. "Nitrogen fixation--making atmospheric nitrogen bioavailable--was also a critical step in the early development of life. We need a good source of nitrogen for proteins and DNA, but the biggest source, the molecular nitrogen that we have in the atmosphere, has a triple bond in it that makes it so inert that it's a killer to get at." Two new studies, to be presented at the February 2003 NASA Astrobiology Institute General Meeting by researchers at Arizona State University, provide evidence for the long-suspected relatedness of the two biochemical pathways, and find hints of other related pathways that may be key to understanding the evolutionary history of both. A critical part of the emerging evolutionary picture seems to be "horizontal gene transfer"--genetic change that occurs by the exchange of genetic material between bacteria. This process allows for sudden evolutionary leaps that are perhaps not possible through gradual genetic change and natural selection. In a paper published in the November 22, 2002 issue of Science, Blankenship, ASU biochemist Jason Raymond and colleagues show through a comparative genomic analysis of five photosynthetic prokaryotic organisms that the genes that code for the intricate molecular complexes that perform photosynthesis seem to have originated through ancient genetic mixing that apparently combined a variety of independently evolved metabolic processes. In one of the Astrobiology meeting papers, "Horizontal Gene Transfer in the Evolution of Nitrogen Fixation," Raymond, Blankenship and Rice University's Janet Siefert do an analysis of the genomes of a larger group of bacteria and archaea, comparing in particular similar genes that code for the protein nitrogenase, a critical enzyme in nitrogen fixation. "In the very early earth, there was probably some available nitrogen in the form of ammonia or something else, so early life forms didn't have to fix nitrogen from the atmosphere. At some point though, things reached a food crisis--you either find someway to get the atmosphere's molecular nitrogen into the cycle or you die. A minimum input of nitrogen can't sustain a big biosphere," noted Blankenship. "Nitrogen fixation is one of the most interesting biological processes because it's so difficult to do chemically. Nitrogenase is a very complex enzyme system that actually breaks molecular nitrogen's triple bond," he said. The researchers find that similar or "homologous" nitrogenase genes exist across a broad range of organisms, and appear to be related to other similar genes coding for proteins involved in photosynthesis, as well as to other genes in archaea and bacteria that do neither photosynthesis nor nitrogen fixation. "We found a group of homologous genes that doesn't correspond to any genes that go with photosynthesis or any that we know in nitrogen fixation--we found these in a wide range of organisms," said Raymond. The analysis suggests that the related genes that code for neither nitrogenase nor enzymes in photosynthesis may be "relics," coding for metabolic pathways that are ancestral to both photosynthesis and nitrogen fixation. Horizontal gene transfer appears to be responsible for the broad distribution of the original gene and for its subsequent divergence and specialization in the metabolic pathways of nitrogen fixation and photosynthesis. In the second paper, "The Evolutionary Relationship between Nitrogen Fixation and Bacteriochlorophyll Synthesis," ASU's Christopher Staples, Blankenship, and Virginia Polytechnic Institute's Biswarup Mukhopadhyay examine the properties of enzymes created by these similar genes and finds that nitrogenase, the photosynthesis related enzymes, and other homologous enzymes all generally belong to a group of enzymes that break apart molecules and are known as reductase enzymes. "We're purifying the proteins that the genes produce and will be looking at catalytic activity. We will test to see how activity differs and also to find what has been conserved and what has been changed in the active sites," said Staples. "Changes in the enzymes' active sites lead to differentiation in regard to what specific molecules they affect." The less-specialized reductase enzymes appear to be ancestral to the others and were perhaps originally important in helping early prokaryotes neutralize toxic substances in their environment. "There is a hypothesis that the ancient reductase, in the presence of a reducing atmosphere, may have been a hydrogen cyanide reductase," said Staples. The team thinks that they have perhaps found a living model for this in Methanococcus jannaschii, a methane-producing archaea that performs neither nitrogen fixation nor photosynthesis but produces a reductase enzyme that the researchers suspect is used to break down hydrogen cyanide. "We're testing to see if these organisms can grow in the presence of cyanide and if they can use cyanide as a nitrogen source," said Staples. "They don't appear to be able to use cyanide exclusively for nitrogen, but they can grow in concentrations of it that would be deadly to most organisms." While the search to discover the evolutionary history of the key chemical processes of the biosphere involves some esoteric genomic and biochemical detective work, Blankenship, Raymond and Staples point out that understanding how the chemical processes of photosynthesis and nitrogen fixation evolved may have some large practical pay-offs. "Understanding the origins of nitrogenase, for example, links to things like the synthesis of fertilizer," said Blankenship. "I come from the Midwest where there are these huge anhydrous ammonia plants that are tremendous users of energy--a fantastic amount of energy goes into the making of ammonia. But that's exactly what this enzyme complex does: make ammonia out of nitrogen. It's a bio solution to this incredibly important and very expensive process of fertilizer production." "There's tremendous appeal in having a bioengineered version of nitrogen fixation. If we understand this complex pathway and its origin and evolution, then we can think more effectively about engineering it into other places. The benefit to society of being able to engineer in nitrogen fixation into most crop plants would be profound," he said. Founded in 1998, the NASA Astrobiology Institute sponsors scientific research in a wide variety of disciplines aimed at asking and answering large and fundamental questions about life in the universe. Astrobiology is an exciting new discipline devoted to the study of life on Earth and elsewhere in the universe--its origin, evolution, distribution, and future. This new area of multidisciplinary study is bringing together the physical and biological sciences to address some of the most fundamental questions of the natural world. The NASA Astrobiology Institute is composed of over 700 researchers distributed at more that 130 research institutions across the United States. Its central offices are located at NASA Ames Research Center, in the heart of Silicon Valley, California. Additional information about the NAI can be found at its web site, http://nai.arc.nasa.gov. Contact: James Hathaway Arizona State University Tempe, Arizona Phone: 480-965-6375 E-mail: jim.hathaway@asu.edu ________________________________________________________________________ COMMON DESERT ORGANISMS MAY HELP IN SEARCH FOR LIFE IN SPACE Arizona State University release 14 February 2003 ASU geomicrobiologist Ferran Garcia-Pichel doesn't just study microorganisms, he studies how they interact with and change their inanimate surroundings. In his work he searches for clues about the first type of organism to dominate the early earth continents--clues he says lead him to believe their descendants, still standing in the deserts of the Southwest, could be similar to the last ones standing in the case of a drastic change. Well, maybe not standing. These tough little critters, which thrive in desolate places and extreme conditions, have no legs. They are the microscopic, single celled cyanobacteria--one of the oldest life forms on Earth. While they may no longer dominate the planet, they are well known from their marine fossil stromatolites, and they still live with us here, forming soil crusts in the Arizona desert. Along these lines, Garcia-Pichel and his collaborators will be presenting several papers and posters at the 2003 NASA Astrobiology Institute General Meeting at Arizona State University. These are on the topics of cyanobacterial community structure, microbial mats, desiccation under different conditions, molecular analysis of calcifying cyanobacteria, comparisons of rDNA sequences from cyanobacteria, as well as the analysis of microbial nitrogen cycling in desert soil crusts. The Earth is about 4 billion years old. Fossilized stromatolites (large deposits left by aquatic communities of cyanobacteria), the most common fossils from the Precambrian period, are known for about 3.5 billion years. That's more than 75% of the earth's history. The size and number of these fossils indicate that cyanobacteria once formed the major ecosystems of the Earth. They were witness to nearly every stage in the earth's evolution. Geochemical evidence shows that cyanobacteria also seem to have played a major role in transforming the early earth into the earth we know today. They invented oxygenic photosynthesis and through this turned the Earth's biosphere from reducing to oxidizing. Studying fossilized cyanobacteria allows us to study what life was like and how it evolved on what was in many ways a different planet. But there may be more to the story. According to Garcia-Pichel, their role in the transformation of early life on land has not been duly recognized, perhaps because terrestrial cyanobacteria do not fossilize as readily as their marine counterparts. Scientists might have to look at indirect evidence--a unique sort of chemical or mineral signature (known as a biosignature) that an organism leaves in its environment. The study of living cyanobacteria and the chemical biosignatures they leave in their environment is essential for the task of looking for past-life evidence on other planets and our own. According to Garcia-Pichel, if we can learn how to recognize the signatures left behind by living terrestrial cyanobacteria on our planet today, we will soon be able to look for them in our geologic record, as well as on other planets. The key to finding their evidence is in figuring out their signatures. Garcia-Pichel hypothesizes that, because they lacked competitors, the early earth's surface may at one time have been completely covered with cyanobacteria. But, as the diversity of life increased, things changed. The advent of plants with leaf-litter blocked much needed sunlight from hitting cyanobacterial communities in the soil. In short, they were crowded out. And this brings Garcia-Pichel and his colleagues to the deserts of the Southwest, where aridity limits plant development, soils are usually bare and cyanobacteria still thrive in communities known as soil crusts. In some of the more pristine portions of the Arizona desert, cyanobacteria essentially lead an existence of withstanding desiccation and the insults of the environment, living one or two millimeters under the surface. From time to time, every monsoon or so, they get wet and come to the surface for a couple hours of activity. In these wet periods they multiply through cellular division and repair all the damage from the dry period. During dry spells, the cyanobacteria (as well as other microbes that live within their community) just lay dormant and suffer what Garcia- Pichel calls "the slings and arrows of the Southwest." To minimize the effects of these slings and arrows, they secrete slime. This slime creates a crust that holds the soil of the cyanobacterial ecosystem in place. This slime essentially cements the desert crust and stabilizes the soil, keeping it from blowing away in the wind. Though cyanobacteria are too small to see with the naked eye, we definitely see their effects. Dust storms in the urban Arizona, as well as the unacceptably high particulate matter count, are enhanced by the loss of cyanobacterial soil communities from agriculture and construction. Garcia-Pichel and his colleagues plan to study modern desert soil crusts, a common and important remnant of cyanobacterial ecosystem, and how they undergo diagenesis--the chemical transformations that occur after burial. Cyanobacteria may be old, but the science and methodologies Garcia- Pichel and his colleagues incorporate in geomicrobiological research are new. According to Garcia-Pichel we are just beginning to understand how microbes can and probably do drive biogeochemical cycles. "This area of geomicrobiology is really, in the Western world, a novelty," says Garcia-Pichel, "people still are amazed that microbes can do things with minerals and rocks." Novelty or not, Garcia-Pichel and his colleagues believe geomicrobiology will help scientists understand the evolution of the earth, and the possible evolution of other planets in this solar system and beyond. Speaking of the applications of their research to the question of Mars, Garcia-Pichel said, "If we postulate that water was not always relegated and then became relegated, and that microbial life was present, what kind of ecosystem would have been the last to be on the surface soils of Mars? It would have been something like desert crusts today. So just there our chances of finding some indirect evidence of life are highest, if we just know how to track, how to teat and how to recognize possible biosignatures from these ecosystems." Contact: James Hathaway Arizona State University Tempe, Arizona Phone: 480-965-6375 E-mail: jim.hathaway@asu.edu ________________________________________________________________________ EARLY MARS: WARM ENOUGH TO MELT WATER? Pennsylvania State University release 14 February 2003 While some researchers believe that only asteroid collisions made Mars warm enough to have running rivers, a Penn State researcher believes the planet had to be continuously warmer to form Mars' deep valleys, but he does not know how the planet warmed up. Some recent research suggests that early Mars was cold most of the time and warmed up only when objects impacted the planet. The impacts would warm the atmosphere and melt water trapped in underground and surface ice, causing rivers to flow and cutting the valleys that rival Arizona's Grand Canyon. "I do not think this is right," said Dr. James F. Kasting, distinguished professor of geosciences and meteorology. "I do not think there was enough time involved to form the types of features that we see on the martian landscape." Kasting believes that a greenhouse effect warmed the planet. However, he has calculated that a carbon dioxide and water greenhouse would not have warmed the planet above the freezing point of water. On Mars, before enough carbon dioxide accumulated in the atmosphere to warm things up, the carbon dioxide would condense into dry ice clouds and eventually there would be ice caps. "It does not seem possible to get above freezing with gaseous carbon dioxide and water," he told attendees at the annual meeting of the American Association for the Advancement of Science today (February 14) in Denver. Which is why some researchers think the planet was never warm. But, according to Kasting, features like Nanedi Vallis, which is a half-mile to over a mile wide in places and over a half mile deep, could not be made during the short time rivers would run after an impact. "The channel at the bottom of Nanedi Vallis is only about 100 feet across," says Kasting. "It took millions of years of constant running water to carve the Grand Canyon. It would take a similar time on Mars." One possible solution is that other greenhouse gases were in play in the martian atmosphere. Methane would be a good candidate, but most sources of methane on Earth are biological. Today's sources of methane are methanogenic bacteria in ruminant animals and rice paddies, but in the pre-oxygen atmosphere of the past, methanobacteria could have lived in many places. "Hillary Justh, a graduate student in geosciences, ran a model of Mars with three atmospheres of carbon dioxide and a tenth of a percent of methane in the atmosphere," adds the Penn State researcher. "Because 3.8 billion years ago the solar luminosity was only 75 percent of what it is today, the model returned an average temperature of minus 13 degrees Fahrenheit." This by itself would not have been enough to allow widespread liquid water. However, the martian surface could have received 20-30 degrees Fahrenheit additional warming from the greenhouse effect of carbon dioxide ice clouds. This might have allowed at least the tropics to remain above freezing. One problem with methane-producing bacteria is that the ones we know here on Earth, both from the fossil record and today, prefer warm environments. Some geologic processes generate methane, but only in small amounts. These processes require water and ultramafic rocks to form serpentine rocks with methane as a by-product. This process occurs at mid-ocean ridges on Earth and can also occur during asteroid collisions that excavate large amounts of mantle material. "We do not really know much about how plate tectonics works on Mars, and even if we did, it is doubtful that enough methane could be generated to create the necessary greenhouse," says Kasting. "Mars probably did need a biological source of methane to form a planet-warming greenhouse." Researchers think that Mars has a supply of water, which is required for all terrestrial life. They also think that volcanic activity on Mars produced a tenth of a percent or so of hydrogen and substantial amounts of carbon dioxide, the two compounds that methanobacteria on Earth need to produce methane. Evidence of these methanobacteria could be found in subsurface fossils or, the bacteria could still be there today. "What we need to do is go and take samples," said Kasting, a member of Penn State's NASA-sponsored Astrobiology Research Center. NASA's Mars Exploration Rover Mission, scheduled to launch later this year, will almost do that. Scheduled to have two fully capable robotic vehicles like the Sojourner, it will sample soils looking for signs of life. However, while the science objectives of the rover missions are to determine if water was present on Mars and whether there are conditions favorable to the preservation of evidence for ancient life, the mission will not return samples to Earth. The first NASA sample- return mission is scheduled for 2020 or later. 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 James Kasting Phone: 814-865-3207 E-mail: kasting@essc.psu.edu Read the original news release at http://www.psu.edu/ur/2003/martianearlyclimate.html. An additional article on this subject is available at http://www.spacedaily.com/news/mars-water-science-03e.html. ________________________________________________________________________ NASA PRESENTS LATEST MARS ODYSSEY OBSERVATIONS NASA note n03-017 14 February 2003 NASA's next Space Science Update (SSU) features recent observations from the camera system on the Mars Odyssey spacecraft. The SSU is on Wednesday, Feb. 19, at 2:00 PM EST. The SSU is in the James E. Webb Auditorium at NASA Headquarters, 300 E Street SW, Washington, DC. Panelists: * Dr. Philip Christensen, principal investigator for Odyssey's thermal emission imaging system, Arizona State University, Tempe. * Dr. Bruce Jakosky, professor, Department of Geological Sciences and the Laboratory for Atmospheric and Space Physics at the University of Colorado, Boulder. * Dr. John (Jack) Mustard, associate professor, Department of Geological Sciences, Brown University, Providence RI. * Dr. Lynn Rothschild, researcher, Ecosystem Science and Technology Branch at NASA's Ames Research Center, Moffet Field, CA. * Dr. Michael Meyer, program scientist for the 2001 Mars Odyssey mission, Office of Space Science at NASA Headquarters. The briefing will be carried live on NASA Television with two-way question-and-answer capability for reporters covering the event from participating NASA centers. NASA TV is broadcast on the GE-2 satellite, Transponder 9C, at 85 degrees west longitude, with vertical polarization, frequency 3880.0 MHz, audio 6.8 MHz. Audio of the broadcast will be available on voice circuit at NASA's Kennedy Space Center, FL, by calling 321/867-1220/1240/1260. For more information about NASA, visit us on the Internet at http://www.nasa.gov. Contact: Nancy Neal NASA Headquarters, Washington, DC Phone: 202-358-2369 ________________________________________________________________________ BUGS FROM THE DEEP MAY BE WINDOW INTO THE ORIGINS OF LIFE--ON EARTH AND BEYOND AAAS release 14 February 2003 Simple life forms are turning up in a surprising variety of below-ground environments, potentially making up 50 percent of the Earth's biomass, scientists said today at the American Association for the Advancement of Science (AAAS) Annual Meeting. From South African gold mines, to cooled seafloor lavas, these subsurface bugs have provided clues to the potential for life on Mars, and the diversity of possible fuel sources for life, including nuclear energy and toxic waste. Similar environments on Mars Life on Mars may exist in "pillow lavas," volcanic rocks that are common on and below the terrestrial seafloor, according to Martin Fisk of Oregon State University. He and his colleagues have investigated the bacteria that live inside pillow lavas on Earth, and found that the microbes seem to be getting their energy from reactions between the glass in the rock and water. Pillow lavas are likely to exist on Mars, Fisk said, and their unusual bulbous shape should make them easy to detect as researchers increase the resolution of photos taken of the planet's surface. "On Earth, microbes live in the glass of pillow lavas. Mars could host life in similar volcanic rocks, although this would require the presence of 'primary producers'--organisms that make organic matter from chemical energy and carbon dioxide," Fisk said. "We're currently working to identify those microbes in Earth's volcanic rocks." Pillow lavas form as seawater rapidly cooled molten lava into volcanic glass. Because these glasses don't have internal crystal structures, the way minerals do, bacteria leave distinctively-shaped tracks as they bore minute holes into the glass. "I sometimes joke that if NASA could get me a pillow lava, I could tell you if anything ever lived in it," Fisk said. He noted, however, that the rock would have to be well-preserved. Life doesn't have to be from another planet in order to survive in seemingly inhospitable conditions, other speakers in the AAAS panel have discovered. Getting in deep Tullis Onstott of Princeton University and his colleagues have found bacterial populations within the walls of South African diamond mines, at depths between 0.8 and 3.3 kilometers. There, temperatures reach up to 60 degrees C and pressures are nearly 250 times as high as on the surface. The microbes that Onstott and his colleagues have found are unlike any living near the Earth's surface. They may even be deriving their energy from nuclear power, at least indirectly. Water plus nuclear radiation emitted from rocks, such as those in the mines produces hydrogen, oxygen, and hydrogen peroxide. The researchers have hypothesized that the bacteria may be using this hydrogen for fuel. "The deep subsurface may be the only place on Earth where communities are using nuclear power that is natural and environmentally safe," Onstott said. The bacterial species may also be ancient. New age estimates from water samples taken from the mines suggest that the water is up to 100 million years old. "Studying these unusual, primitive microorganisms helps us appreciate life's ability to take hold in a remarkable variety of environments. It may even help us understand how life evolved on Earth or other planets," Onstott said. The versatility of life Closer to home, Susan Brantley of Pennsylvania State University has grown bacteria on different mineral surfaces in her lab. Her goal is to understand how the microbes extract elements from their environment to sustain themselves. "Early life had to solve all the same problems" that these bacteria do, Brantley said. She thinks that some bacteria's body chemistry may incorporate elements, such as nickel, that were most accessible when life emerged on Earth. "Snapshots of the chemistry of the early Earth may be caught in these organisms," said Brantley. Research in thermal hot springs also reveals bacteria's adaptability to all kinds of environments where photosynthesis cannot take place. Everett Shock of Arizona State University studies life in hot springs such as those in Yellowstone National Park. Shock and his colleagues have identified more than a hundred possible types of metabolic reactions in which the organisms derive their energy from chemical reactions. While these include familiar reactions involving hydrogen, iron, sulfur, nitrogen, and organic compounds, they also involve more unusual elements, such as arsenic, selenium, and uranium. Other metal-reducing bacteria may have potential for use in environmental cleanup efforts, according to John Zachara of the Pacific Northwest National Laboratory. Another unsung role played by bacteria involves the formation of large deposits of methane hydrate on the seafloor. These deposits are solid under the high pressures and low temperatures at the seafloor. If that pressure was reduced or the temperature increased, however, the hydrate would likely vaporize, producing large volumes of methane, a potent greenhouse gas. Scientists have proposed that methane hydrates may have had a hand in past climate change episodes, or may be a possible fuel source. Frederick Colwell of the Idaho National Engineering and Environmental Laboratory has identified some of the microbes that make the methane in these deposits. Colwell and his colleagues are now trying to determine the rate at which these bugs produce methane, which should help researchers predict where methane hydrates are located. The American Association for the Advancement of Science (AAAS) is the world's largest general scientific society, and publisher of the journal, Science. Founded in 1848, AAAS serves 134,000 members as well as 272 affiliates, representing 10 million scientists. For more information on the AAAS, see the web site at www.aaas.org. Additional news from the AAAS Annual Meeting may be found online at www.eurekalert.org. Contact: American Association for the Advancement of Science Washington, DC Phone: 303-228-8301 Monica Amarelo, e-mail: mamarelo@aaas.org Ginger Pinholster, e-mail: gpinhols@aaas.org An additional article on this subject is available at http://www.spacedaily.com/news/life-03k.html. ________________________________________________________________________ EUROPA SURFACE MISSIONS NECESSARY STEP IN EXTRATERRESTRIAL SEARCH Arizona State University release 14 February 2003 Scientists have long considered Europa, the smallest of the four Galilean moons orbiting Jupiter, as a prime candidate for life outside Earth because it is one of the few places in the solar system where liquid water may be found. Any future Europa exploration should focus on the identification of sites where signs of past or present life can be found and studied, says Ron Greeley, an ASU geology professor. Greeley, who heads up the Europa Astrobiology research at ASU, is co- author of an abstract paper on potential Europa habitats presented at the 2003 NASA Astrobiology Institute General Meeting held February 10 12 at ASU. The meeting brought more than 500 researchers from throughout the United States to discuss the latest developments in astrobiology. The NASA Astrobiology Institute includes a multitude of diverse disciplines including chemistry, biology, geology, microscopy and astronomy. Greeley said assuming life arises quickly under appropriate formative conditions, life could be present wherever there is liquid water, a source of energy and essential elements. Europa is roughly the size of the moon, and is believed to have a rocky interior and an outer shell of ice--and possibly liquid water--about 60 to 100 miles thick. Scientists say mounting evidence for the existence of a salty liquid ocean beneath Europa's icy crust is exciting because that is just the environment that could provide favorable conditions for present life, or where signs of past life may be preserved. Europa has been studied for years by examining data collected by the unmanned Galileo spacecraft's onboard science instruments, but Greeley and his NASA colleagues believe future studies of Europa will need to focus on surface units, particularly in areas where geologic processes have caused the satellite's icy crust to melt, and where organisms would be protected from radiation and provided with an adequate food supply. "Now that the Galileo mission is nearly completed, it is time for researchers to sift through the images to shape the current state-of- knowledge about the satellite and pose scientific questions to be addressed by future missions," said ASU researcher Patricio Figueredo, Greeley's colleague, and first author of the Europa habitat paper. Although it is not clear to researchers how far a liquid ocean is from the surface, Figueredo says scientists must now piece together the visible evolution history of Europa and determine how different pathways of energy, materials and nutrient interactions would affect possible ecosystems in the satellite. A second paper presented at the conference starts from the idea that a liquid ocean is present on Europa to offer one explanation as to why sulfate is found on the surface of the satellite. Sulfate has been readily observed on Europa's surface by a stereoscopic instrument aboard Galileo. If the sulfate is from a liquid ocean, it is likely to have been formed by high-temperature fluids released at the oceanic floor from the satellite's silicate mantle. When these high-temperature fluids are cooled quickly, it would provide the right conditions to support life, says ASU's Mikhail Zolotov and Everett Shock, geology researchers who presented the paper, "Autotrophic Sulfate Reduction in a Hydrothermally Formed Ocean on Europa." The differentiated internal structure of Europa implies that high temperature interaction of water and rocks occurred at least once in the satellite's history. It is plausible some volcanic activity is also occurring on present day Europa, driven by tidal forces. The authors believe high-temperature fluids from the satellite's rocky core flow into the icy-cold ocean above. Similarly, this phenomenon occurs on Earth, under the ocean floor within mid-ocean ridge volcanoes. These deep-sea hydrothermal vents--known more commonly as black smokers--force sulfur-rich, high-temperature water (about 350-degrees Celsius) out onto the ocean floor through chimney-like, volcanic rock structures. As the hot, mineral-rich water rushes out of the chimney and mixes with cold ocean bottom water, it precipitates a variety of minerals as tiny particles that, in turn, provide energy to marine life. When sulfate from seawater mixes with the vent fluid, it can be a source of energy for life through a process called autotrophic sulfate reduction. "On Earth, sulfates can be reduced through biologic activity in oxygen- free sedimentary basins or in organic-rich oceanic sediments," said Shock. "Although the amount of energy on Europa could be insufficient to allow these biologic organisms to persist throughout the ocean's history, a periodic supply of organic compounds or other environmental factors introduced into the ocean could maintain life over time. If this process is detected in the chemical composition of Europa's oceanic water, it would be highly suggestive of the involvement of ancient life." Contact: Lynette Summerill Media Relations & Public Information Phone: 480-965-4823 E-mail: lsummer@asu.edu ________________________________________________________________________ ROLL WITH THE ROVERS AND "EXPLORE MARS" FEBRUARY 19 NASA/KSC release 19-03 15 February 2003 NASA hosts "Explore Mars!"--a Cape Canaveral-area community and family day focusing on the upcoming Mars Exploration Rover-2003 mission, on Wednesday, February 19, 9:00 AM - 7:00 PM, at the Radisson Resort at the Port Convention Center, 8701 Astronaut Blvd., Cape Canaveral, FL. Students and the general public will learn about Florida's key role as NASA's "Gateway to Mars," and meet with scientists, engineers, educators and others working on these and other Mars exploration missions. Children of all ages are invited to playtime with working robot rovers. The Mars Exploration Rovers, described as two robot geologists, are being prepared for launch this spring aboard Boeing Delta II rockets from the Cape Canaveral Air Force Station, and are due to land on and start exploring Mars in January 2004. Once on Mars, they will communicate with controllers at NASA's Jet Propulsion Laboratory in Pasadena, CA, where the rovers were built. For more information or to schedule a speaker to talk to your school or community about Mars Exploration, contact the NASA Jet Propulsion Laboratory Resident Office at Kennedy Space Center at 321-867-3731. See the Mars Exploration Program web site at http://www.mars.jpl.nasa.gov. Contact: George H. Diller NASA John F. Kennedy Space Center Kennedy Space Center, Florida 32899 Phone: 321-867-2468 Read the original news release at http://www- pao.ksc.nasa.gov/kscpao/release/2003/19-03.htm. ________________________________________________________________________ LOS ALAMOS MAKES FIRST MAP OF ICE ON MARS Los Alamos National Laboratory release 15 February 2003 Lurking just beneath the surface of Mars is enough water to cover the entire planet ankle-deep, says Los Alamos National Laboratory scientist Bill Feldman. Feldman on Saturday released the first global map of hydrogen distribution identified by instruments aboard NASA's Mars Odyssey spacecraft and offered initial minimum estimates of the total amount of water stored near the martian surface. His presentation came at the annual meeting of the American Association for the Advancement of Science in Denver. For nearly a year, Los Alamos' neutron spectrometer has been carefully mapping the hydrogen content of the planet's surface by measuring changes in neutrons given off by soil, an indicator of hydrogen likely in the form of water-ice, within about 35 degrees latitude of the north and south poles. A color map is available at http://www.lanl.gov/worldview/news/pdf/MarsWater.pdf online. "It's becoming increasingly clear that Mars has enough water to support future human exploration," Feldman said. "In fact, there's enough to cover the entire planet to a depth of at least five inches, and we've only analyzed the top few feet of soil." The new map is based on views of the red planet through more than half a martian year of 687 Earth days, so researchers have been able to see both poles without obstruction by the seasonal polar caps of frozen carbon dioxide, dry ice. From about 55 degrees latitude to the poles, Mars has extensive deposits of soils that are rich in water-ice, bearing an average of 50 percent water by mass. In other words, Feldman said, a typical pound of soil scooped up in those polar regions would yield an average of half a pound of water if it were baked in an oven. The tell-tale traces of hydrogen, and therefore the presence of hydrated minerals, also are found in lower concentrations closer to Mars' equator, ranging from two- to 10-percent water by mass. Surprisingly, two large areas, one within Arabia Terra, the 1,900-mile-wide martian desert, and another on the opposite side of the planet, show indications of relatively large concentrations of sub-surface hydrogen. "The big reason we're so confident now is that we have an absolute calibration of our results," Feldman said. He and his Los Alamos colleagues recently compared their neutron spectrometer readings as Odyssey flew over the north pole during early spring, when the dry-ice ground cover was thickest, against simulations of the spectrometer's response to a thick layer of pure dry ice. This allowed them to calibrate the Odyssey readings with a known martian soil type. "We're sure there's dry-ice precipitation at the poles because the temperature of the ground cover is within the range for dry ice. And we can tell how thick the icecaps are, from the measured intensity of hydrogen gamma rays coming from underneath the icecaps," Feldman said. "We went from thick dry ice to a low-hydrogen abundance calibration when we applied our 'neutron ruler' at Mars' equatorial latitudes. We were surprised to see such huge amounts of hydrogen at those lower latitudes: close to 10 percent in some places." How did water vapor get into the subsurface soils and into rocks farther beneath the surface of Mars? The effort to answer that question and to reconstruct the martian hydrologic cycle will occupy Feldman and his colleagues for years to come. Hydrogen is only absorbed chemically near rock surfaces, but Mars geology appears to be rich in minerals as zeolites, clays and magnesium sulfate, all of which can retain significant amounts of water. "This is material that has absorbed the hydrogen chemically and has retained it for millions of years," Feldman explained. The team also studied meteor craters more than 250 miles across such as Schiaparelli and discovered that the water content in the crater's center is reduced. Scientists are attracted to two possible theories of how all that water got into the martian soils and rocks. The vast water icecaps at the poles may be the source. The thickness of the icecaps themselves may be enough to bottle up geothermal heat from below, increasing the temperature at the bottom and melting the bottom layer of the icecaps, which then could feed a global water table. On the other hand, there is evidence that about a million years or so ago, Mars' axis was tilted about 35 degrees, which might have caused the polar icecaps to evaporate and briefly create enough water in the atmosphere to make ice stable planet-wide. The resultant thick layer of frost may then have combined chemically with hydrogen-hungry soils and rocks. "We're not ready yet to precisely describe the abundance and stratigraphy of these deposits at high latitudes, but the neutron spectrometer shows water ice close to the surface in many locations, and buried elsewhere beneath several inches of dry soils," Feldman said. "Some theories predict these deposits may extend a half mile or more beneath the surface; if so, their total water content may be sufficient to account for the missing water budget of Mars." In fact, a team of Los Alamos scientists has begun a research project to interpret the Mars Odyssey data and their ramifications for the history of Mars' climate. The project is funded through the Laboratory Directed Research and Development program--which funds innovative science with a portion of the Laboratory's operating budget--and seeks to develop a global martian hydrology model, using vast amounts of remote sensing data, topography maps and experimental results on water loading of minerals. Researchers working with Feldman on the Odyssey project include Tom Prettyman, Bob Tokar, Kurt Moore, Herb Funsten, David Lawrence and Richard Elphic. Los Alamos' neutron spectrometer, a more sensitive version of the instrument that found water ice on the moon five years ago, is one component of the gamma-ray spectrometer suite of instruments aboard Odyssey. Professor William V. Boynton of the University of Arizona leads the gamma-ray spectrometer team. The neutron spectrometer looks for neutrons generated when cosmic rays slam into the nuclei of atoms on the planet's surface, ejecting neutrons skyward with enough energy to reach the Odyssey spacecraft 250 miles above the surface. Elements create their own unique distribution of neutron energy--fast, thermal or epithermal--and these neutron flux signatures indicate what elements make up the soil and how they are distributed. Thermal neutrons are low-energy neutrons in thermal contact with the soil; epithermal neutrons are intermediate, scattering down in energy after bouncing off soil material; and fast neutrons are the highest-energy neutrons produced in the interaction between high- energy galactic cosmic rays and the soil. By looking for a decrease in epithermal neutron flux, researchers can locate hydrogen. Hydrogen in the soil efficiently absorbs the energy from neutrons, reducing their flux in the surface and also the flux that escapes the surface to space where it is detected by the spectrometer. Since hydrogen is likely in the form of water-ice at high latitudes, the spectrometer can measure directly, a yard or so deep into the martian surface, the amount of ice and how it changes with the seasons. Mars Odyssey was launched from Cape Canaveral Air Force Station in April 2001 and arrived in martian orbit in late October 2001. During the rest of the spacecraft's 917-day science mission, Los Alamos' neutron spectrometer will continue to improve the hydrogen map and solve more martian moisture mysteries. Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Odyssey mission for NASA's Office of Space Science in Washington, DC. Investigators at Arizona State University in Tempe, the University of Arizona in Tucson and NASA's Johnson Space Center, Houston, operate the science instruments. Additional science partners are located at the Russian Aviation and Space Agency and at Los Alamos National Laboratories, New Mexico. Lockheed Martin Astronautics, Denver, the prime contractor for the project, developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL. Los Alamos National Laboratory is operated by the University of California for the National Nuclear Security Administration (NNSA) of the U.S. Department of Energy and works in partnership with NNSA's Sandia and Lawrence Livermore national laboratories to support NNSA in its mission. Los Alamos enhances global security by ensuring safety and confidence in the U.S. nuclear stockpile, developing technologies to reduce threats from weapons of mass destruction and improving the environmental and nuclear materials legacy of the cold war. Los Alamos' capabilities assist the nation in addressing energy, environment, infrastructure and biological security problems. Contact: Jim Danneskiold DOE/Los Alamos National Laboratory Phone: 505-667-1640 E-mail: jdanneskiold@lanl.gov Read the original news release at http://www.eurekalert.org/pub_releases/2003-02/danl-lam021303.php. An additional article on this subject is available at http://www.spacedaily.com/news/mars-water-science-03d.html. ________________________________________________________________________ CHINA TO SEND MAN INTO SPACE THIS FALL, WITH SIGHTS ON MOON From Agence France-Presse and SpaceDaily 16 February 2003 China plans to send its first human into space this fall and has the ability to send astronauts to the moon, reports said Sunday, citing space program officials. On Saturday, "(our) journalist got information from authoritative persons from China's space program that China will launch as planned this autumn the first manned spacecraft," the Beijing Star Daily said. Unlike China's previous spaceflights, which were unmanned, the manned flight will have the number of instruments used for in-space experiments reduced to make room for astronauts to conduct observation missions, the report said. Only one or two astronauts will be selected from a pool of 14 trained astronauts to man the spacecraft, called Shenzhou V, the paper quoted Zhang Houying, general director of a department in China's manned space program, as saying. Read the full story at http://www.spacedaily.com/2003/030216081927.x6bpyoe3.html. ________________________________________________________________________ GREAT IMPACT DEBATE, PART II: MUCH ADO ABOUT NOTHING? Moderated by Don Yeomans From Astrobiology Magazine 17 February 2003 The second part in our "Great Impact Debate" series brings together a group of scientists who are experts on asteroids and comets. Today's debate concerns the emphasis the media and others place on the threat of asteroid and comet impacts. Given that large bodies hit the Earth only very rarely, is the concern about impacts unjustified? Don Yeomans: To sum up part of the discussion from last week, near-Earth comets and asteroids are important in understanding the origin of our solar system. The planets, including our own Earth, were formed from collections of these near-Earth objects (NEOs). Life itself may have been enabled by the water and carbon-based materials brought to the early Earth as a result of comet and asteroid impacts. NEOs are among the easiest objects within the solar system to visit with spacecraft, so in the future NEOs may provide the raw materials (e.g., water, minerals, metals) for human survival and for building structures in space. Of course, most of the newspaper accounts reporting upon near-Earth comets and asteroids have nothing to do with their scientific importance. As last week's debate made clear, a hot topic is the effect of past NEO impacts on Earth and the possibility of future impacts. In fact, most of the press reports about NEOs have to do with those that could impact Earth and possibly cause a significant number of deaths. With regard to the possible threats that NEOs pose, scientists can point to no person in recorded history who has been killed by an asteroid or comet. On the other hand, we can all cite examples of people who have been killed by auto accidents, floods, hurricanes, and airplane crashes. So why all the fuss about comet and asteroid impacts with Earth? Benny Peiser: I am not so sure about the accurateness of the claim that "no one in recorded history has been killed by an asteroid or comet." As a matter of fact, there are historical records that give accounts of suspected meteorite impacts leading to fatalities. For example, a number of historical reports exist about an alleged disaster in 1490 AD, said to have occurred in the Chinese city of Qingyang (Shaanxi province). According to these reports, over 10,000 people were killed when "stones fell from the sky like rain." Perhaps, as John Lewis has suggested in his book, Rain of Iron and Ice (1996), it would be wiser to say, "No one in recorded history has ever been killed by a meteorite in the presence of a meteorite scientist and a medical doctor". Clark Chapman: Still, the average American's chances of dying as a result of an asteroid impact [are] about the same as an average American's chances of dying in a tornado. The distinction is that many tornadoes occur each year, and some of them kill up to dozens of people, whereas big asteroid impacts occur very rarely, but might kill millions or even billions of people. Several U.S. citizens die every day, one at a time, by accidental electrocution. Roughly the same number die in the very few jet airliner crashes each year, where hundreds die at one time. Airline crashes are relatively rare events: there were only two days during 2001 on which people died in airliner crashes in the United States; one was September 11th. Asteroid impacts are just a more extreme case of a rare but extraordinarily deadly event. Since the chances of death and destruction by cosmic impact are on the same order for Americans as death by airliner crash, flood, tornado, and other hazards society takes seriously, it is reasonable that the impact hazard be taken seriously. In fact, an asteroid impact is a much more serious hazard, statistically speaking, than many other hazards we have experienced in the last few decades, including death by terrorism, by nuclear power plant accident, by shark attacks, etc. And cosmic impacts--if large enough--are nearly unique (along with nuclear war and perhaps some "Andromeda Strain" pandemic) of having the possibility of sending civilization back into a Dark Age or even exterminating our species--although the chances of such a cataclysmic impact are extremely tiny. Historically, society has not spent equally to mitigate various hazards, in terms of dollars per life saved or damage averted. The comparisons I have cited do not necessarily require that society must spend the same amount on NEO searches and mitigation measures as we do, for instance, on tornado research, but policy-makers ought to at least seriously examine the impact hazard. Joe Veverka: Today asteroids and comets are largely irrelevant to life on Earth on any reasonable human time scale. So why all the fuss? Probably the most important reason is that most humans worry a lot and are not equipped to evaluate certain risks properly. If there is vigorous publicity concerning any potential danger to status quo and well being, some people will worry and some will even become terrified-- no matter how trivial the alleged danger really is when viewed in comparison with the other dangers that surround us. The fact that some individuals feel threatened by asteroids and comets does not imply anything about the reality or severity of the threat. Exactly the same statement can be made about dozens of other "dangers" peddled by well- established advocacy groups to scare the public and thereby gain support and funds. Thus, the reasons for the fuss are very clear and fundamentally very human. They have very little to do with what is really out there in space, or with what really are the dangers to life, society, and environment posed by comets and asteroids. Clark Chapman: Joe Veverka's answer implies that there are other catastrophes that have been more deadly, at least in the last century. That is illustrated in this chart, produced for an asteroid workshop by John Pike. The statistical hazard from asteroids and comets would be a slice of pie in this chart that is roughly the same size as the one for volcanoes. Joe Veverka: Regarding the advocacy groups I mentioned, there are at least three different, well-established advocacy groups whose future and welfare depends on focusing the public's attention on the "threat from space." (The term "advocacy group" is a polite one. A much more accurate but cruder term can be found in Jean Giraudoux's play "The Mad Women of Chaillot".) The first advocacy group is the media. If all else fails, stories about comets and asteroids destroying New York or Tokyo sell newspapers and magazines and make for popular TV fodder. Second, there is a strong advocacy group among astronomers. They want more resources devoted to studying comets and asteroids. Publicizing the "threat from space" has certainly proven an effective means for generating government support for the study of NEOs. Finally, there is an evolving engineering/industrial/military advocacy group that promulgates the "threat from space" because members of this group want public support to build and provide the defenses that will shield us from this "peril." Benny Peiser: I'm afraid I regard as misleading allegations that the NEO community (or the missile defense community for that matter) deliberately exaggerates the impact risk for selfish reasons. In reality, most NEO researchers--in particular those in the U.S.--have underrated the potential hazards from space. NASA only reluctantly began to address the issue following the considerable "wake-up call" caused by the impact of comet Shoemaker-Levy 9 on Jupiter in 1994. Without these harmless reminders, I doubt whether NASA would have established even a rudimentary program to inventory the number of large asteroids out there. Alan Harris: In response to Joe Veverka's point on advocacy groups, it is often the case that those who are most qualified to offer advice also have special interests in the matters of their expertise. You go to a car salesman to buy a car, but if you are not equipped to evaluate what he tells you, you risk being "taken for a ride." The same is true even for consulting a doctor about an ailment. By Joe's argument, you should never buy a car or see a doctor because any advice you receive may be tainted by special interests! Benny Peiser: Professional astronomers and planetary scientists study comets and asteroids for a better insight into the evolution of our solar system. In contrast to this outlook, the vast majority of people around the world are not bothered with the specific aspects of NEO research. What they want to know, first and foremost, is quite simple: Do these objects pose any threat to me, my family, or to the stability of our societies? The information provided by scientists has not been very reassuring. What do we expect the interested public to think about claims that the K/T impact was "unique" and that it was the only impact that caused a mass extinction? How credible are such sweeping statements, given how incomplete our current understanding remains regarding the mechanisms, effects, and rate of hypervelocity impacts? Peter Ward: David Kring has suggested to me that another K/T type impact could be devastating for the animal and plant world. New calculations show that our planet would go into another "Snowball Earth event" like the one that occurred 600 million years ago, when the oceans froze over. While bacteria might readily survive such calamitous impacts, our new understanding from the record of the Earth's mass extinctions clearly shows that plants and animals are very susceptible to extinction in the wake of an impact. Anything that would increase the rate of large asteroid or comet impacts on the Earth--or on any inhabited planet in this or any other galaxy-- would be detrimental to the evolution and survival of higher life forms. But what determines impact rates? That depends on how many comets and asteroids exist in a particular planetary system. It also depends on how often those objects are perturbed from safe orbits that parallel the Earth's orbit to new, Earth-crossing orbits that might, sooner or later, result in a catastrophic K/T or Permian-type mass extinction. Our understanding of those events now leads us to believe that any comet or asteroid greater than 20 kilometers in diameter that strikes the Earth will result in the complete annihilation of complex life--animals and higher plants. How many times in our galaxy alone has life finally evolved to the equivalent of our planets and animals on some far distant planet, only to be utterly destroyed by an impact? Surely this has been a commonplace event in the vast cosmos. Yet it appears that Jupiter, with its stable circular orbit far from the sun, assures the Earth a low number of impacts resulting in mass extinctions. Jupiter sweeps up and scatters away most of the dangerous Earth-orbit-crossing comets and asteroids. In 1995, astronomer George Wetherill calculated that without Jupiter, the impact rate on Earth by comets and asteroids would be 10,000 times higher. Under such bombardment it is hard to conceive of how complex life would survive. Jupiter acts as our cosmic guardian, making our neighborhood vastly safer through a gravitational Planetary Protection plan. Benny Peiser: Given the exceptionally low odds of large impacts, astronomers are rightly staggered by the public's concern with and the media's obsession about the impact hazard. I think one reason for this bewilderment has to do with a genuine lack of sociological understanding. After all, the irrational unease about the impact risk needs to be seen in context of a global public that, to an overwhelming extent, still adhere to religious beliefs that predict cosmic catastrophes of apocalyptic proportions. For hundreds of millions of devout Christians and Muslims, comets and asteroids are extremely relevant to life on Earth--not for any scientific reasons, but as traditional portents of doom. In the past, one way to deal with such celestial dread was to deny that there is any cosmic threat whatsoever. For most of the last 2,000 years, astronomers have been extremely reluctant to acknowledge that there are any risks from space. This approach, however, is no longer available to modern science and any attempt to discount, minimize, or ridicule the impact hazard will backfire. That's why I am uncomfortable with ongoing efforts to underestimate or belittle the concerns people have about the impact hazard. Read the original article at http://www.astrobio.net/news/article378.html. ________________________________________________________________________ BEFORE COLUMBIA: A PERSONAL VIEW By Bruce Moomaw From SpaceDaily 17 February 2003 On the night of February 1, SpaceDaily published "The Cold War Space Age Is Over", which I had written when I was "white-faced with rage", but which on reexamination I still thought held up. In it, I flatly accused NASA of a constant 30-year stream of deliberate, methodical and outrageous "claims" about the supposed low cost, high safety and high usefulness first of the Shuttle and then of the Space Station--in order to maintain as much as possible of the freakishly bloated funding it had received during the days of the Apollo program and the Moon Race. And I said that those claims amounted to a gigantic swindle of the American taxpayers amounting to some $150 billion--and that another direct result of those claims was a total of 14 unnecessarily dead astronauts. Needless to say, such a piece kicked up a fuss. Some readers both strongly agreed with my editorial and defended its timing. Others, to put it mildly, feel differently. Read the full article at http://www.spacedaily.com/news/oped-03n1.html. ________________________________________________________________________ ASTEROID COVER-UP PROPOSAL CAUSES NEO COMMUNITY A CREDIBILITY CRISIS By Benny Peiser From SpaceDaily 17 February 2003 Just when you thought we had learned our lessons from past communication debacles and PR fiascoes, bizarre statements at the Denver AAAS meeting have plunged the NEO community into another crisis of credibility. "Don't tell Public of Doomsday Asteroid", reads the headline in today's The Times, while The Independent warns: "Armageddon Asteroids best kept secret." The Internet (Drudge Report, etc.) and fringe web sites are already brimming with gloating links to this asteroid-cover-up story while doomsday prophets and conspiracy-theorists can't believe their good fortune: "We've told you so!" What happened? How could a harmless NEO panel generate conspiracy- advocating headlines around the world that will seriously damage the integrity of the NEO community? Read the full article at http://www.spacedaily.com/news/deepimpact- 03d.html. ________________________________________________________________________ NEW ADDITIONS TO THE ASTROBIOLOGY INDEX By David J. Thomas http://www.lyon.edu/webdata/users/dthomas/astrobiology/astrobiology.html 17 February 2003 Astrobiology, exobiology and terraformation articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_articles1. html R. R. Britt, 2003. Mars ice is mostly water: good for biologists, bad for terraformers. Space.com. S. Byrne and A. P. Ingersoll, 2003. A sublimation model for martian south polar ice features. Science, 299(5609):1051-1053. California Institute of Technology, 2003. The martian polar caps are almost entirely water ice. SpaceDaily. Carnegie Mellon University, 2003. Carnegie Mellon scientist to develop probes to detect life on Mars. SpaceDaily. L. David, 2003. Astrobiologists say Prometheus Jupiter mission should have landing craft. Space.com. L. David, 2003. Gully search supports liquid water on Mars. Space.com. L. David, 2003. Life zone on Venus possible. Space.com. L. David, 2003. NASA's Astrobiology Institute general meeting begins. Space.com. Los Alamos National Laboratory, 2003. Los Alamos makes first map of ice on Mars. SpaceDaily. NASA Ames Research Center, 2003. NASA study shows how water may have flowed on ancient Mars. SpaceDaily. Pennsylvania State University, 2003. Early Mars: warm enough to melt water? SpaceDaily. T. N. Titus, H. H. Kieffer and P. R. Christensen, 2003. Exposed water ice discovered near the south pole of Mars. Science, 299(5609):1048- 1051. Terrestrial extreme environments articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_articles2. html American Association for the Advancement of Science, 2003. Bugs from the deep may be window into the origins of life. SpaceDaily. Human space exploration and microgravity effects articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_articles3. html Agence France-Presse, 2003. China to send man into space this Fall, with sights on Moon. SpaceDaily. China Daily, 2003. China's manned space mission stays on course for October launch. SpaceDaily. Evolutionary biology and chemistry articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_articles5. html A. M. Rosenthal, 2003. Murchison's amino acids: tainted evidence? Astrobiology Magazine. Planetary protection articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_articles6. html B. Peiser, 2003. Asteroid cover-up proposal causes NEO community a credibility crisis. SpaceDaily. D. Yeomans, 2003. The great impact debate, part II: much ado about nothing? Astrobiology Magazine. ________________________________________________________________________ CONTINUING COVERAGE OF THE COLUMBIA DISASTER By David J. Thomas 17 February 2003 The investigation of the Columbia tragedy continues to make headlines in both space and general media. I have included (below) a non-exhaustive list of links to recent articles on the subject. http://www.cnn.com/2003/TECH/space/02/12/nasa.memo/index.html http://www.cnn.com/2003/TECH/space/02/11/sprj.colu.station.interview/ind ex.html http://www.cnn.com/2003/ALLPOLITICS/02/11/sprj.colu.space.politics/index .html http://www.cnn.com/2003/TECH/space/02/12/shuttle.photo.ap/index.html http://www.nytimes.com/2003/02/11/national/nationalspecial/11SHUT.html?t h http://www.nytimes.com/2003/02/12/national/nationalspecial/12SHUT.html?t h http://www.nytimes.com/2003/02/13/national/nationalspecial/13SHUT.html?t h http://www.nytimes.com/2003/02/14/national/nationalspecial/14SHUT.html?t h http://www.nytimes.com/2003/02/15/national/nationalspecial/15SHUT.html?t h http://www.sciam.com/print_version.cfm?articleID=000E76D3-F389-1E43- 89E0809EC588EEDF http://www.space.com/missionlaunches/sts107_briefingPM_030210.html http://www.space.com/missionlaunches/sts107_spysats_030211.html http://www.space.com/businesstechnology/technology/nasa_robots_030209.ht ml http://www.space.com/missionlaunches/sts107_imagerequest_030213.html http://www.space.com/missionlaunches/sts107_sensor_030213.html http://www.space.com/missionlaunches/sts107_remains_030212.html http://www.space.com/missionlaunches/columbia_questions_answers.html http://www.space.com/missionlaunches/sts107_starfire_030212.html http://www.spacedaily.com/2003/030210233037.l20erhwz.html http://www.spacedaily.com/news/oped-03k.html http://www.spacedaily.com/news/oped-03m.html http://www.spacedaily.com/news/oped-03n1.html http://www.spacedaily.com/2003/030212231044.t969l5up.html http://www.spacedaily.com/2003/030214005515.nctsreie.html http://www.spacedaily.com/2003/030214165918.7s0gbczm.html ________________________________________________________________________ CASSINI SIGNIFICANT EVENTS NASA/JPL release 6-12 February 2003 The most recent spacecraft telemetry was acquired from the Madrid tracking station on Wednesday, February 12. 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. Instrument activities for C35 came to a close with Radio and Plasma Wave High Frequency Receiver calibrations and high rate observations, execution of the Cosmic Dust Analyzer (CDA) flight software (FSW) checkout mini-sequence, and powering off of the instruments in anticipation of the start of C36 and the ACS and CDS flight software checkouts. All instruments except for the Visual and Infrared Mapping Spectrometer (VIMS) powered off via background sequence commands. VIMS will stay powered on but in sleep mode and muted. The Ka-band translator also remains powered on, and the remote sensing pallet heater was turned on due to VIMS entering sleep mode. The CDA FSW checkout activity executed nominally. The new FSW was loaded from the non- default SSR partition and the various thresholds/voltages/data rate/read-out queue/SEL protection parameters set up properly. The instrument was successfully articulated and left in a measurement position at the end of the checkout. Science and housekeeping data packets and test pulses were received as expected. CDA also articulated to a safe position in preparation for the C36 FSW checkouts and Trajectory Correction Maneuver 19 in C37. Spacecraft activities prior to the conclusion of C35 included the uplink of real-time commands to provide information and set parameters in anticipation of the ACS/CDS FSW checkouts. Commands included CDS clear error logs, CDS set ACS global variables to zero for ACS flight computer swap during ACS FSW loading, memory readouts of the flight software partitions, a readout of ACS reaction wheel assembly slow speed accumulation statistics, and uplink of the C36 SSR Management background sequence. ACS also executed commands in the background sequence to move the spacecraft to a new waypoint in preparation for the FSW checkout phase. C36 began execution on Saturday. Initial activities included uplink of ACS FSW and CDS FSW to the Solid State Recorder, and memory readouts of the ACS and CDS FSW partitions. Instrument Operations internal testing has begun for an engineering version of EKGEN. EKGEN is the operator-interface component of the Events Kernel system planned for delivery in September of 2003. EKGEN will be used to create EKernels from a sequence Predicted Events File, and will publish the results to the Distributed Object Manager (DOM) using conventional DOM standards. Data acquisition statistics from the recently concluded Radio Science Gravitational Wave Experiment #2 (GWE) are now available. They confirm a highly successful, around-the-clock operations period lasting 40 days. Much of the success was due to excellent support from the Deep Space Network. Of the X-band uplink/Ka-band downlink data expected at DSS-25 in Goldstone, California, 93% was acquired. Much of the missing data is attributed to the X-band transmitter tripping problem. Of the Ka-band uplink/Ka-band downlink data expected, 95% was acquired. Of the coherent X-band data expected, 93% was acquired. Of the coherent X-band data expected at DSS-45 in Canberra, Australia, 95% was acquired. Finally, of the coherent X-band data expected at the Madrid DSS-65, DSS- 54, and DSS-63 facilities, 99% was acquired. The port 1 reports from Uplink Operations and the Spacecraft Operations Office are now available on the C37 Science Planning web site. Official DSN allocations were delivered for the first three weeks of C37. Requested passes have been confirmed so changes are not expected to the time ordered listing. The remaining passes to be assigned for the sequence should be verified by the end of the week. The second official input port occurred for Science Operations Plan implementation for tour sequences S15/S16. The products are being merged and processed and will be handed off to ACS for the end-to-end pointing validation. The first preliminary input port also occurred for implementation of S17/S18. The products are being merged and reviewed for fidelity. The official port is scheduled for February 24, 2003. 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, Calif., manages the Cassini mission for NASA's Office of Space Science, Washington, D.C. ________________________________________________________________________ INTERNATIONAL SPACE STATION SCIENCE UPDATE NASA release 03-066 12 February 2003 Science operations continue on the International Space Station. Basic and applied research is being conducted in biology, physics, chemistry, ecology, medicine, materials science, manufacturing and the long-term effects of space flight on humans. During the past week, the Expedition Six crewmembers, Commander Ken Bowersox, Flight Engineer Nikolay Budarin and NASA Station Science Officer Don Pettit, completed several sessions in support of the Human Research Facility (HRF). The HRF is a floor-to-ceiling, facility-class rack located in the Station's Destiny laboratory. It is designed to support human life science investigations, such as the Pulmonary Function in Flight (PuFF) experiment. The PuFF experiment evaluates how the lungs function in space. Little is known about how the lungs can be affected by long-term exposure to microgravity like the near- weightlessness inside the Space Station. The science data recorded from previous life sciences experiments was beamed down to a team at NASA's Johnson Space Center in Houston. Pettit read the EVA Radiation Monitoring (EVARM) experiment dosimeter badges and downloaded the data from the reader to the HRF laptop computer. The data from the badges is read once a week and then downloaded to the computer on a bi-weekly basis. The badges measured radiation absorbed by the eyes, skin, and blood-forming organs when previous expedition and Shuttle crews wore them outside during spacewalks. The dosimeters are located at strategic locations inside the Destiny laboratory, where they measure radiation inside the laboratory. Scientists will compare data collected by the EVARM badges with data collected by other nearby radiation measurement devices inside Destiny. On Tuesday, February 4, the Russian Progress re-supply ship arrived at the Station on schedule with a load of supplies, including scientific equipment. After the Progress docked, the crew began unloading equipment and supplies, including a new power distribution box and an electronics module for the Microgravity Science Glovebox. On February 5, Pettit installed the new parts, powered up the Glovebox and activated the facility. This resulted in a circuit breaker trip, and further activity was put on hold. The Glovebox team on the ground is working with the European Space Agency, which built the facility, to develop a troubleshooting plan for the Station crew. The Glovebox supports several physical science experiments, providing a contained work volume for crews to safely work with experiments involving fumes, fluids, flames or loose particles. Several experiments are onboard the Station and are ready to resume inside the Glovebox when it is restored to working order. The crew set up a camera in the Station's high-quality optical window, and students from 30 schools across the globe used it to do their geography lessons. Students remotely controlled the special digital camera through the Internet and took 767 images of Earth during the past week. They selected and photographed Earth's coastlines, mountain ranges and other geographic areas of interest. The Earth Knowledge Acquired by Middle School Students (EarthKAM) educational program team posted the photographs on the Internet. They are available to the public and participating classrooms around the world. This experiment has been performed on several Station expeditions, giving thousands of students a chance to study Earth from the unique vantage point of space. Images are available at http://datasystems@earthkam.ucsd.edu. The crew took photographs this week as part of the Crew Earth Observation (CEO) program. The crew had the opportunity to photograph many places in India, Africa, Panama, Puerto Rico, South America, and Asia. The CEO science team praised recent detailed shots of glaciers on the west side of the Andes, which is often covered by clouds and difficult to photograph. Upcoming science activities for the crew include work with the FOOT/Ground Reaction Forces During Space Flight (FOOT) experiment. FOOT characterizes the stress on the bones and muscles in the lower extremities. The next FOOT session is planned for Thursday, February 13. The Payload Operations Center at NASA's Marshall Space Flight Center (MSFC) in Huntsville, AL, manages all science research experiment operations aboard the Space Station. For supporting materials for this news release, such as photographs, fact sheets, video and audio files and more, visit the MSFC web site at www.msfc.nasa.gov/news. Contacts: Dolores Beasley NASA Headquarters, Washington, DC Phone: 202-358-1753 Steve Roy NASA Marshall Space Flight Center, Huntsville, AL Phone: 256-544-0034 ________________________________________________________________________ MARS ODYSSEY THEMIS IMAGES NASA/JPL/ASU release 10-14 February 2003 Arabia Terra (Released 10 February 2003) http://themis.la.asu.edu/zoom-20030210a.html Arabia Terra Streaks (Released 11 February 2003) http://themis.la.asu.edu/zoom-20030211a.html A Tale of Two Craters (Released 12 February 2003 http://themis.la.asu.edu/zoom-20030212a.html Ice Clouds (Released 13 February 2003) http://themis.la.asu.edu/zoom-20030213a.html Layered Deposits in Terby Crater (Released 14 February 2003) http://themis.la.asu.edu/zoom-20030214a.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 14 February 2003 This past week, the Stardust flight team had use of the antennas of JPL's Deep Space Network on three separate occasions. Data relayed from the spacecraft on these contacts indicated Stardust is healthy and all subsystems continue to run normally. During one of the passes, the Deep Space Network took the opportunity to give their new Network Simplification Plan a deep space workout. The Network Simplification Plan is an upgrade of hardware and software currently being implemented at the various Deep Space Network ground stations. The demonstration was a success. Speaking of the Deep Space Network, the Stardust team has incorporated additional "dish time" into the new programming that will soon be uplinked to the spacecraft. The supplementary Deep Space Network passes will be utilized to transmit images stored in the spacecraft's memory of the Pleiades star cluster. These Pleiades images were taken by Stardust's navigation camera and will be used to evaluate performance of the spacecraft camera's periscope. Information on the present position and orbits of the Stardust spacecraft and Comet Wild 2 may be found on the "Where Is Stardust Right Now?" web page located at http://stardust.jpl.nasa.gov/mission/scnow.html. 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 7.