MARSBUGS: The Electronic Astrobiology Newsletter Volume 10, Number 18, 5 May 2003. Editor/Publisher: David J. Thomas, Ph.D., Science Division, Lyon College, Batesville, AR 72503-2317, USA. dthomas@lyon.edu 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 editor, except for specific articles, in which instance copyright exists with the author/authors. The editor does not condone "spamming" of subscribers. Readers would appreciate it if others would not send unsolicited e-mail using the Marsbugs mailing lists. Persons who have information that may be of interest to subscribers of Marsbugs should send that information to the editor. E-mail subscriptions are free, and may be obtained by contacting the editor. 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) NASA SATELLITE MEASURES EARTH'S CARBON METABOLISM NASA/GSFC release 2) SYRACUSE UNIVERSITY GEOLOGISTS RAISE QUESTIONS ABOUT CONTROVERSIAL THEORY OF SPECIES SURVIVAL ACROSS TIME By Judy Holmes 3) ALIEN WORLDS THROUGH ARTISTS' EYES By Robert Roy Britt 4) NASA CONTEST EXPLORES DESIGNS FOR FUTURE COLONIES IN SPACE NASA/ARC release 03-31AR 5) ARECIBO DIARIES (5): THE ROMANCE, DRAMA AND NORMALITY OF THE OBSERVATORY By Seth Shostak 6) MOON SOCIETY AND ARTEMIS SOCIETY ENDORSE SPACE SETTLEMENT INITIATIVE From SpaceDaily 7) WORMS FOUND ALIVE IN SHUTTLE WRECKAGE From Associated Press and CNN 8) LOOKING FOR LIFE OF ANY SHAPE OR FORM From ESA Science News 9) PLANETARY PROTECTION: AN INTEGRAL PART OF MISSION PREPARATIONS By Margaret S. Race 10) RECOOKING THE RECIPE FOR PREBIOTIC SOUP Scripps Institution of Oceanography release 11) NASA BRINGS "MARS AT THE MALL" TO FLORIDA MAY 9 AND 10 NASA/JPL/KSC release 12) TANK-INSPIRED ROBOT SET TO HUNT MICROBES ON MARS From Agence France-Presse and SpaceDaily 13) PLoS BIOLOGY NOW OPEN TO ACCEPT PAPERS Public Library of Science release 14) DINNER WITH DARWIN From Astrobiology Magazine 15) PHOTOSYNTHESIS IN THE ABYSS By Stephen Hart 16) NEW ADDITIONS TO THE ASTROBIOLOGY INDEX By David J. Thomas 17) CONTINUING COVERAGE OF THE COLUMBIA DISASTER By David J. Thomas 18) CASSINI SIGNIFICANT EVENTS NASA/JPL release 19) ESA'S MARS EXPRESS READY FOR LAUNCH ESA release 28-2003 20) MARS GLOBAL SURVEYOR IMAGES NASA/JPL/MSSS release 21) MARS ODYSSEY THEMIS IMAGES NASA/JPL/ASU release ________________________________________________________________________ NASA SATELLITE MEASURES EARTH'S CARBON METABOLISM NASA/GSFC release 21 April 2003 In honor of the Earth Day celebration, NASA scientists unveiled the first consistent and continuous global measurements of Earth's "metabolism." Data from the Terra and Aqua satellites are helping scientists frequently update maps of the rate at which plant life on Earth is absorbing carbon out of the atmosphere. Combining space-based measurements of a range of plant properties collected by the Moderate Resolution Imaging Spectroradiometer (MODIS) with a suite of other satellite and surface-based measurements, NASA scientists produce composite maps of our world's "net primary production" every 8 days. This new measurement is called net production because it indicates how much carbon dioxide is taken in by vegetation during photosynthesis minus how much is given off during respiration. Scientists expect this global measure of the biological productivity of plants to yield new insights into how the Earth's carbon cycle works, a critical step toward solving the climate change puzzle. The rate of carbon fixation through photosynthesis is a basic property of life on planet Earth. It is the basis for capturing and storing the energy that fuels our world's living systems and forms the foundation of the food webs. The oxygen we breathe is a byproduct of this photosynthesis. According to its creators, these new net primary productivity maps provide a fascinating new insight into the intimate connection between the living world and the physical world. "We are literally watching the global garden grow," says Steve Running, MODIS Science Team member and director of the Numerical Terradynamic Simulation Group at the University of Montana. "We now have a regular, consistent, calibrated and near-real-time measure of a major component of the global carbon cycle for the first time. This measure can also be the basis for monitoring the expansion of deserts, the effects of droughts, and any impacts climate change may have on vegetation growth, health, and seasonality." On land, notes Running, photosynthesis is the foundation for agricultural crop production, rangeland grazing capacity and forest growth. "We also anticipate that our new productivity maps should help to significantly improve analysis of global crop commodities." The new maps show that the highest mid-summer productivity rates are found at temperate latitudes with mild climates and not at tropical latitudes, as some might have expected. However, tropical forests are more productive over a full year because of their longer growing season. Viewing the global maps sequentially in a 2-year movie reveals some fantastic seasonal cycles of plant growth, especially at high latitudes across North America, Europe, and Asia. The movie also reveals the almost immediate response of land plants to changing daily weather patterns. [http://earthobservatory.nasa.gov/Newsroom/NPP/Images/psn.modis.2002.350 .jpg] 2002 net primary productivity. This false-color map represents the Earth's carbon "metabolism"-the rate at which plants absorbed carbon out of the atmosphere. The map shows the global, annual average of the net productivity of vegetation on land and in the ocean during 2002. The yellow and red areas show the highest rates, ranging from 2 to 3 kilograms of carbon taken in per square meter per year. The green, blue, and purple shades show progressively lower productivity. [http://earthobservatory.nasa.gov/Newsroom/NPP/Images/psn.modis.seasonal .jpg] Seasonal comparison of net primary productivity. In any given year, tropical rainforests are generally the most productive places on Earth. Still, the ongoing productivity near the sea's surface, over such a widespread area of the globe, makes the ocean roughly as productive as the land. However, plant life in the ocean is somewhat more buffered and therefore not as directly driven by weather patterns, states Wayne Esaias, biological oceanographer at NASA's Goddard Space Flight Center. The growth of microscopic marine plants (phytoplankton) in the ocean responds more to seasonal changes-currents, temperature, and sunlight. So, whereas certain areas on land will swing abruptly from very low to very high rates of photosynthetic activity, biological productivity in the ocean is ongoing steadily and is spread over much wider areas. "It doesn't surprise Earth scientists, but the public might be surprised to learn that there is so much photosynthesis in the oceans," observes Esaias. "When you average the productivity rates over the whole world, the ocean is roughly equal to the land." Esaias is examining how plant productivity rates in the ocean vary in response to changes in the ocean's current patterns. In particular, he says, these new primary productivity maps will help fisheries scientists understand why there are good catches some years and poor catches in others. For the last two decades, using data from earlier satellite sensors, scientists have been able to map global concentrations of chlorophyll, the green pigment marine and land plants use for photosynthesis. But it was still a leap for scientists to estimate how much carbon was converted to organic material by plants-a measure now routinely provided by the net primary productivity maps. The new MODIS maps mark a major milestone in the careers of both Running and Esaias--a milestone they have been working toward for more than 20 years. "As Earth systems science began in the 1980s, ecology was way behind the atmosphere and oceans disciplines in achieving a global perspective because our training was on single organisms (i.e., dissecting frogs and counting dandelions), so we had no global-scale theory or measurements," states Running. "But this new measurement attests that ecology is now catching up in global science." Esaias adds that this is just the first cut and there is much work left to do to refine their maps. "The world is a big place and we are only just beginning to fully understand and validate what we see in our data around the globe and over time. We know we can make improvements in some areas, but it is good to now have the global context to pull together research that is being done locally in various regions around the world." Launched in December 1999 and May 2002, Terra and Aqua are the flagships of the Earth Observing System series of satellites and a central part of NASA's Earth Science Enterprise. The mission of the Earth Science Enterprise is to help us understand and protect our home planet. Read the original news release at http://earthobservatory.nasa.gov/Newsroom/NPP/npp.html. An additional article on this subject is available at http://spaceflightnow.com/news/n0304/28carbon/. ________________________________________________________________________ SYRACUSE UNIVERSITY GEOLOGISTS RAISE QUESTIONS ABOUT CONTROVERSIAL THEORY OF SPECIES SURVIVAL ACROSS TIME By Judy Holmes Syracuse University release 28 April 2003 A recent study by a team of Syracuse University geologists has punched holes in a relatively new theory of species evolution called coordinated stasis; the theories involved are based on findings from fossil-bearing rocks that underlie Central New York. The SU study was published in Geology, the premier journal of the Geological Society of America. First proposed in 1995 by Carl Brett of the University of Cincinnati and Gordon Baird of the State University of New York at Fredonia, coordinated stasis attempts to describe the emergence and disappearance of species across geologic time by suggesting that species living together in the same environment go through long periods of stability- some six million years-and then undergo a rapid, almost complete turnover, during which old species disappear and new ones emerge. Until 1995, most researchers believed that species emerged and disappeared independent of each other throughout time. "Our study suggests that there may be more variability in species composition through time than predicted by coordinated stasis," says Linda Ivany, one of the co-authors of the SU study. "It will be the blueprint study against which other researchers will present their data sets to determine whether coordinated stasis is present or not." The SU study resulted from research that lead author Nicole Bonuso conducted for her master's thesis project in the Department of Earth Sciences and an analysis of some 20 years of fossil data-38,000 specimens-compiled by Bonuso's faculty advisors and co-authors Cathryn Newton, dean of The College of Arts and Sciences, and Professor James C. Brower. The data were collected from the Central New York Middle Devonian Hamilton Group, the original test case for coordinated stasis, which is characterized by beautifully preserved and richly diverse fossils that date back more than six million years. Unlike previous studies, which were based only on the presence or absence of species, Bonuso, currently a doctoral student at the University of Southern California, Los Angeles, looked at "proportional abundance data," meaning that she looked at all of the species that were present and at how abundant they were across a six million year span. "When the first results started coming in, I got very excited," Bonuso says. "Coordinated stasis did not hold up to our rigorous statistical analysis within the area we tested. That doesn't mean coordinated stasis never occurs or doesn't occur at other times. More research is needed." Adds Ivany: "We found that while the most abundant species persisted across the span of time as would be predicted by coordinated stasis, the less common species showed more variability. And relatively speaking, the abundant species represented only a few of all the species that were represented in the data set. The findings suggest that coordinated stasis holds for the most abundant species but not for the less common ones, which seem to come and go through time independent of each other." Ivany says the point of the study was not so much to prove or disprove coordinated stasis, but rather to compare the results of a high- resolution study using abundance data from the Syracuse area to the original formulation of coordinated stasis as presented by Brett and Baird. In addition, the study explicitly identified a consistent, statistical method to determine whether coordinated stasis is present in the fossil record in a given area. "If coordinated stasis is showing up with a reasonable degree of frequency in the history of life, we then need to look at what it is telling us about the relationships among evolution, ecology and environmental change," she says. The study, published as the lead article in the December 2002 issue of Geology, was the second published work to come out of Bonuso's master's thesis. The first article, published a year ago in "Palaeogeography, Palaeoclimatology, Palaeoecology" was based on an analysis of fossils she collected from the uppermost layer of the Hamilton Group, which completed Newton's and Brower's 20-year effort to collect species data from the entire geological unit. One of the goals of the first study, which Bonuso also co-authored with Newton, Brower and Ivany, was to find an appropriate statistical method to test the hypothesis of coordinated stasis using only the data from the upper-most layer. The methodology developed for the first study was expanded to analyze the data previously collected by Newton and Brower, which led to the Geology article. "If it were not for the excellent mentoring from all my advisors throughout the course of the project, this important research would not have been accomplished," Bonuso says. "This was Cathy Newton's original idea wrapped with Jim Brower's methodology, and they let me in on it. I just picked up where they left off." Contact: Judy Holmes E-mail: jlholmes@syr.edu Read the original news release at http://sunews.syr.edu/fullstory.asp?id=4220315. An additional article on this subject is available at http://www.spacedaily.com/news/life-03s.html. ________________________________________________________________________ ALIEN WORLDS THROUGH ARTISTS' EYES By Robert Roy Britt From Space.com 29 April 2003 There are more than 100 known planets around other stars, and astronomers tell us there are billions. Some are cold. Some are hot. Some are stable. Some are doomed. Many are like Jupiter. Others are so large they stretch the very definition of planethood. Future discoveries will almost surely yield rocky planets like Earth. Astronomers detect these faraway places by noting a gravitational wobble in the star, or by the chance passage of the planet in front of its star, causing a tiny dip in the amount of starlight that reaches Earth. Yet so far all of these extrasolar worlds are known through limited data and by their shadows. We "see" them only through artists' eyes. The artists also interpret sketchy data collected on nascent solar systems, where worlds are presently forming around newborn stars in setups destined to look a lot like the nine-planet configuration we're familiar with. Many artistic impressions of other worlds are rooted solid scientific data. Others are more imaginative but no less plausible given the current lack of knowledge about the universe beyond our little corner of it. Read the full article at http://www.space.com/scienceastronomy/alien_worlds_030429-1.html. ________________________________________________________________________ NASA CONTEST EXPLORES DESIGNS FOR FUTURE COLONIES IN SPACE NASA/ARC release 03-31AR 28 April 2003 According to students from around the world, the prospects are bright for people someday living in space. The annual Space Settlement Contest, sponsored by the Fundamental Space Biology Program at NASA Ames Research Center, Moffett Field, CA, builds upon students' natural fascination with space and space exploration. The contest challenges students in grades six through 12 to investigate and then develop designs for a permanent, orbital space colony. The founders of the contest envision that these students will one day make orbital colonies a reality. "The Space Settlement Contest is a part of NASA's educational effort to inspire the next generation of explorers," said Al Globus, NASA scientist and one of the founding members of the competition. "The contest is designed to spark a student's interest in math and science and to develop the ideas and skills that will make orbital colonies a possibility. It is all about training the people who will one day colonize the solar system." Recently announced, the 2003 grand prize winners were two middle school students from Iasi, Romania. Horia Mihail Teodorescu and Lucian Gabriel Bahrin submitted the design for an orbital colony called Teba 1. The design was chosen as the winner by a panel of NASA scientists from a field of 89 designs submitted by 307 students from the United States, Austria, India, Japan and Romania. Entries were judged on how well the students addressed the fundamental issues involved with building and maintaining an orbital colony, such as gravity generation, life support, food production and resource management. Teba 1 best addressed these issues and has earned a permanent place on the NASA advanced supercomputing Web site along with grand prizes winners from the past 10 years. For the contest, the Fundamental Space Biology Program created a Web site that provided students access to a wealth of electronic resources to help develop their designs. The Web site contains presentations, articles, images, Web links and research on colonizing space from NASA and other space settlement experts. "Students and teachers use this site as a resource in preparing designs that later will be submitted for evaluation by NASA scientists. The site includes a comprehensive eight-week course on preparing an orbital settlement design, complete with objectives aligned with the U.S. National Science Standards, as well as an online quiz," said Bryan Yager, coordinator of the Space Settlement Contest. The grand prize winners, along with the first-, second- and third-place winners in the individual and small group categories, will be invited to visit NASA Ames in June. The students will present their designs, talk to NASA scientists and tour the fundamental space biology laboratories. All students participating in the contest received an official Space Settlement Contest certificate. The Fundamental Space Biology Program, funded by NASA's Office of Biological and Physical Research, investigates fundamental biological processes through space flight and ground-based research. The program brings together state-of-the-art science and technology and seeks to answer the most basic questions regarding the evolution, development and function of living systems. To view the winning submissions and for more information about the Space Settlement Contest, visit http://www.nas.nasa.gov/NAS/SpaceSettlement/. For information about the Fundamental Space Biology Program, visit http://fundamentalbiology.arc.nasa.gov/. For information about NASA's Office of Biological and Physical Research visit http://spaceresearch.nasa.gov/. Contact: Jonas Diño NASA Ames Research Center, Moffett Field, CA Phone: 650-604-5612 or 650-604-9000 E-mail: jonas.dino@nasa.gov ________________________________________________________________________ ARECIBO DIARIES (5): THE ROMANCE, DRAMA AND NORMALITY OF THE OBSERVATORY By Seth Shostak From Space.com 29 April 2003 Do you remember that opening episode of "The X-Files'" second season? For some reason, the principals had to hack their way into the Arecibo Observatory. The facility had been closed down (funding problems, no doubt), and was decaying in the undergrowth. The observing building was a forlorn structure, strangled by tentacles of aggressive vegetation. It felt like "Indiana Jones and the Lost Telescope." It's a romantic image, and one that's apparently widespread. A few years ago, a television production company came to Arecibo to tape a segment on SETI, and upon arrival in Puerto Rico they booked a jeep for me to ride onto the site as the cameras rolled. They figured that to show up for work probably involved machetes and the ability to lift fallen tree trunks from a dirt path. It doesn't, of course. Yes, you can use a jeep to get to the Observatory if that's your vehicular bent. You can also use a stretch limo. The roads are paved, and trunk-free. There are thousands of tons of steel and aluminum, and countless yards of concrete in this telescope. That stuff didn't get here by mule on a rutted road. It's America's gothic view of science that conjures up such misperceptions. Our archetypical image of researchers is that they're lonely, gnarly old guys toiling away in damp, stone-walled basements, festooned with sparking Jacob's Ladders. Well, there are about 140 employees at Arecibo plus a half-dozen SETI Institute folks, and none, I'm gratified to note, are gnarly. The walls are dry, and open sparks are verboten--they would cause egregious radio interference. Read the full article at http://www.space.com/searchforlife/shostak_arecibo_5_030429.html. ________________________________________________________________________ MOON SOCIETY AND ARTEMIS SOCIETY ENDORSE SPACE SETTLEMENT INITIATIVE From SpaceDaily 30 April 2003 Two leading space activist foundations, The Moon Society and the Artemis Society, have endorsed the Space Settlement Initiative. The timing of the endorsements is particularly significant. Following the Columbia accident, several other key space advocacy groups now say they are ready to publicly espouse the idea of space settlement--after years of being afraid to do so very loudly for fear it sounded too "way out". A recent meeting of those space activist groups strongly endorsed space settlement as a goal but, as always, failed to support any plan directly targeted to promote space settlement. The Moon Society and the Artemis Society, on the other hand, have now endorsed the Space Settlement Initiative as the most realistic and achievable method for encouraging private enterprise in outer space. The premise of the Initiative is simple: the federal government cannot afford to spend the billions of dollars it will take to go to Mars or even to go back to the Moon. Therefore, the capitalization will have to be raised from private enterprise, and the only way to interest investors in privately funded space development is to make that investment potentially very profitable. Read the full article at http://www.spacedaily.com/news/mars-base- 03b.html. ________________________________________________________________________ WORMS FOUND ALIVE IN SHUTTLE WRECKAGE From Associated Press and CNN 1 May 2003 Hundreds of worms from a science experiment aboard the space shuttle Columbia have been found alive in the wreckage, NASA said Wednesday. The worms, known as C. elegans, were found in debris in Texas several weeks ago. Technicians sorting through the debris at Kennedy Space Center in Florida didn't open the containers of worms and dead moss cells until this week. ..."To my knowledge, these are the only live experiments that have been located and identified," said Bruce Buckingham, a NASA spokesman at the Kennedy Space Center. The worms and moss were in the same nine-pound locker located in the mid-deck of the space shuttle. The worms were placed in six canisters, each holding eight Petri dishes. Read the full article at http://www.cnn.com/2003/TECH/space/04/30/shuttle.worms.ap/index.html. An additional article on this subject is available at http://www.space.com/missionlaunches/sts107_worms_030501.html. ________________________________________________________________________ LOOKING FOR LIFE OF ANY SHAPE OR FORM From ESA Science News 1 May 2003 On 25 April 25 1953, James D. Watson and Francis H. Crick published an historic paper in Nature that would change the fate of modern science. They proposed that DNA, the molecule of complex life forms, had the shape of a double helix. Today, scientists from all areas are working together to answer the ultimate question: can life (in any shape or form) exist anywhere else in the Universe? Astrobiology is a young interdisciplinary science that tries to find answers to tough questions. Experts want to know how life begins and evolve and if it can exist anywhere else outside the Earth. Life in the Universe--as we know it--began with the synthesis of some key elements: hydrogen, carbon, oxygen, nitrogen, sulfur, and phosphorus. Carbon is the element that allows the formation of organic compounds that form the base of more complex molecules. Nucleic acids or sugars, constituting DNA and RNA, are examples of such complex molecules. With telescopes like ISO, the European Space Agency Infrared Space Observatory, studying molecules and organic compounds in space began to pay off. Operating from 1995 to 1998, ISO performed nearly 30 000 observations. Scientists have discovered more than a hundred complex organic molecules in space so far, some of them widespread in our Galaxy. "Most of them", explains Alberto Salama, ISO Project Scientist, "form close to where stars form and near to old dying stars. Violent phenomena take place there, like high-velocity winds and high-energy fluxes, so the chemistry of the gas changes greatly and many molecules can form. Strong radiation from the stars destroys some molecules. Others survive in the interstellar space and may be incorporated on dust grains". Water is one of the basic (inorganic) molecules needed for life to develop. How wet is space? "ISO found water basically everywhere. It was in our Solar System, including the atmospheres of the giant planets and Saturn's moon Titan, in the areas around stars, in the cold interstellar medium, and in other galaxies. In an interstellar gas cloud in Orion, we discovered enough water generated every day to fill all of the Earth's oceans 60 times!" exclaims Salama. Water and complex organic molecules are there, but just having them in space is not enough for life to develop. DNA and RNA molecules, for example, use a life-replication mechanism that is very safe, ensuring the maintenance, stability, and diversity of its basic components. These molecules have distinct components, a very complex structure. It is unlikely you would found them just anywhere. Is it therefore also unlikely that there is life anywhere else? Many astrobiologists are optimistic. Playing with the same components of DNA and RNA, you can make other molecules that can store genetic information, even with a different structure. There are also other types of nucleic acids, called peptide- nucleic acids (PNA), which have different backbones. They contain no sugars, no phosphates, just amino-acid derivatives. Forming compounds of nucleic acids might therefore be easier than we think. Moreover, some nucleobases, like adenine and guanine, form easily and are quite stable. Scientists do not rule out these complex molecules also being in interstellar space. They have already been found on 4.6 thousand million-year-old meteorites. Other sugar derivatives have also already been discovered on meteorites. Many ESA missions have a clear astrobiological side. For example, Rosetta will land on a comet and Huygens on Saturn's moon Titan. Their analyses will help us to better understand so-called prebiotic chemical processes on those bodies. Mars Express, scheduled for launch in June 2003, will be able to identify signs of water in liquid, solid, or vapor form on Mars. Its lander, Beagle 2, will take a good chemical and morphological look at its landing site, looking for water in the soil, on rocks, and in the martian atmosphere. It will investigate the existence of carbonate minerals and organic residues to detect possible signs of past or present life. From 2005, Columbus, the European research module on the International Space Station, will be using a new space biology tool, EXPOSE. EXPOSE will examine whether, and to what extent, meteorites may offer enough protection for life to continue after their long existence in space. Scientists identified the underlying structure of life on Earth only a relatively short time ago. Now they are taking the first steps to find the chemicals of life far away in space and study them. Who or what will they discover? Read the original article at http://sci.esa.int/content/news/index.cfm?aid=1&cid=1&oid=32166. ________________________________________________________________________ PLANETARY PROTECTION: AN INTEGRAL PART OF MISSION PREPARATIONS By Margaret S. Race From Space.com 1 May 2003 In the coming weeks, workers at Kennedy Space Center will finalize preparations for the upcoming Mars Exploration Rover (MER) missions. If all goes as planned, the two spacecraft will launch in June, complete their one-way trips to Mars in January 2004, and land in two distinctly different locations on the planet. The first rover will explore an area at Gusev Crater, which appears to have once held a lake, and the second will probe Meridiani Planum, an area with deposits of hematite located halfway around the planet. Each rover over will examine its landing site for geological evidence of past liquid water activity and environmental conditions potentially hospitable to either past or present life. While the missions aren't life detection missions per se, they'll contribute valuable physical, chemical and geological details about Mars in advance of other one-way missions, and perhaps someday, round-trip sample return missions. Long before the MER missions were readied for their highly public launch, NASA's scientists and engineers have worried behind the scenes about all the "little things" that could impact the mission--some literally down to the invisible microbes that could contaminate the spacecraft, or interfere with the scientific equipment or the environments they'll visit. Since the early years of the space program, scientists have expressed concern about planetary protection--that is, the prevention of human-caused biological cross-contamination between Earth and other bodies in the solar system. "Hitchhiker" bacteria and other organisms on spacecraft and equipment might cause irreversible changes in the environments of other planets or interfere with scientific exploration on them. In practical terms, the concerns are twofold: avoiding (1) forward contamination, the transport of terrestrial microbes on outbound spacecraft, and (2) back contamination, the introduction onto Earth of contamination or life-forms that could be returned from space. Both concerns are covered in provision of the Outer Space Treaty of 1967, as well as in NASA policies and requirements. Read the full article at http://www.space.com/searchforlife/seti_race_protect_0230501.html. ________________________________________________________________________ RECOOKING THE RECIPE FOR PREBIOTIC SOUP Scripps Institution of Oceanography release 1 May 2003 In the fall of 1952, Stanley Miller, now a chemistry professor emeritus at the University of California, San Diego (UCSD), began simulating primitive earthly conditions in an experiment that produced the basic building blocks of life. When he published the results in Science on May 15 the following year, he kick-started research on the origin of life and transformed modern thinking on a dormant area of science. Jeffrey Bada, a professor of marine chemistry at Scripps Institution of Oceanography, UCSD, and an expert on origin of life processes, revisits the famous "Miller experiment" in a report published in the May 2 issue of Science. "Up to Miller's experiment there was a large vacuum in our understanding of how life began on the earth," said Bada, who coauthored the report with Antonio Lazcano, a scientist at the Universidad Nacional Autûnoma de Mèxico, and is a visiting scholar at UCSD in Miller's laboratory. "Up to that point no one had demonstrated how compounds like amino acids could be synthesized under possible early Earth conditions." Bada and Lazcano's essay traces the history of the Miller experiment, which originated when the late Nobel Laureate and UCSD Chemistry Professor Harold Urey discussed the idea behind the experiment in a lecture at the University of Chicago. Miller, then a graduate student in the audience, eventually presented Urey the idea of a prebiotic synthesis experiment applying an electric discharge to a mixture of methane, ammonia, water vapor, and hydrogen. Urey eventually agreed to the idea. During Miller's experiment, the mixture of gases was circulated through a liquid water solution and continuously zapped with the electric spark, which substituted for lightning. The surprising products of the process were "biochemically significant" compounds such as amino acids, hydroxy acids, and urea. Thus, with Urey's guidance, Miller had produced the basic building blocks of contemporary life forms on Earth. "In the early 1950s, several groups were attempting organic synthesis under primitive conditions," Bada and Lazcano note in their essay. "But it was the Miller experiment, placed in the Darwinian perspective provided by Oparin's ideas and deeply rooted in the 19th century tradition of synthetic organic chemistry, that almost overnight transformed the study of the origin of life into a respectable field of inquiry." Bada and Lazcano also note that Miller's study was published only a few weeks after Watson and Crick's landmark paper on the DNA double-helix model and the authors highlight the important link between the two young fields in the years that followed. Bada will be giving a public lecture on the 50th anniversary of the Miller experiment at 3:00 PM on Tuesday, June 10, 2003, during "Celebrating 50 Years of Prebiotic Chemistry," a public event at the Robinson Building Complex Auditorium, Graduate School of International Relations & Pacific Studies (IR/PS), Thurgood Marshall College, UCSD campus. The event, which also features Gerald Joyce of the Scripps Research Institute, is sponsored by the NASA Specialized Center of Research and Training (NSCORT) in Exobiology, the UCSD Dean of Physical Sciences, the Department of Chemistry and Biochemistry at UCSD, and the National Aeronautics and Space Administration. For information about the event, call 858-534-1891 or visit the NSCORT/Exobiology web site at http://exobio.ucsd.edu. Scripps Institution of Oceanography on the web: http://scripps.ucsd.edu Scripps News on the web: http://scrippsnews.ucsd.edu Scripps Centennial on the web: http://scripps100.ucsd.edu Scripps Institution of Oceanography at the University of California, San Diego, is one of the oldest, largest, and most important centers for global science research and graduate training in the world. The scientific scope of the institution has grown since its founding in 1903. A century of Scripps science has had an invaluable impact on oceanography, on understanding of the earth, and on society. More than 300 research programs are under way today in a wide range of scientific areas. Scripps operates one of the largest U.S. academic fleets with four oceanographic research ships and one research platform for worldwide exploration. Now plunging boldly into the 21st century, Scripps is celebrating its centennial in 2003 (http://scripps100.ucsd.edu). Contact: Mario Aguilera or Cindy Clark Scripps Communications Office Scripps Institution of Oceanography Phone: 858-534-3624 E-mail: scrippsnews@ucsd.edu http://scrippsnews.ucsd.edu Read the original news release at http://scrippsnews.ucsd.edu/article_detail.cfm?article_num=564. ________________________________________________________________________ NASA BRINGS "MARS AT THE MALL" TO FLORIDA MAY 9 AND 10 NASA/JPL/KSC release 2 May 2003 Part of Merritt Square Mall in Merritt Island, Fla., will take on an unearthly tone during two days of "Mars at the Mall" days presented by NASA on May 9 and 10 to celebrate Florida's role as America's gateway to Mars. The event, complete with a 3-D martian mural, models of NASA Mars rovers and a gallery of Mars pictures, will share excitement about two new rover missions to Mars scheduled to launch from Cape Canaveral in June. Preparations for launch are under way at NASA's Kennedy Space Center. The new Mars Exploration Rovers will be able to explore farther and examine rocks better than the Sojourner rover that studied one site on Mars in 1997. Mars at the Mall will feature models both of Sojourner and a new Mars Exploration Rover. To give an unforgettable impression of how the Mars rovers can cope with bumps in their path, a very lightweight rover model will roll over children who lie on the ground. Visitors will wear three-dimensional viewing glasses to examine a mural of the Pathfinder landing site and get a sense of the Mars landscape receding in front of them to the horizon. Pictures taken by two orbiting NASA spacecraft, Mars Global Surveyor and Mars Odyssey, will show visitors a sampling of the diversity of martian surface features. Those two orbiters, both still active, have provided evidence of erosion by liquid water on Mars and of large amounts of ice close to the surface. A meteorite that came from Mars will be on display. NASA personnel will be available throughout the event to answer questions about Mars exploration. Part of NASA's mission is to inspire the next generation of explorers. The launch-opportunity period for the first Mars Exploration Rover begins June 5. The second rover could launch as soon as June 25. Both will arrive at Mars in January 2004, but at two different sites about halfway around the planet from each other. One site is a crater that may have once been a lake. The other has a deposit of a mineral that usually forms only under wet conditions. Additional information about the Mars Exploration Rovers is available online at http://mars.jpl.nasa.gov/mer. The Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, CA, manages the missions for NASA's Office of Space Science, Washington, DC. Contacts: Guy Webster NASA Jet Propulsion Laboratory, Pasadena, CA Phone: 818-354-6278 George Diller NASA John F. Kennedy Space Center, FL Phone: 321-867-2468 ________________________________________________________________________ TANK-INSPIRED ROBOT SET TO HUNT MICROBES ON MARS From Agence France-Presse and SpaceDaily 2 May 2003 Scientists in Britain have designed a tank-inspired robot set to hunt microbes on Mars and establish whether human colonies could survive in the hostile environment of the Red Planet. Researchers say they turned to military-inspired caterpillar tracks which change shape as they roll over obstacles. The 40,000-euro (45,000 dollars) research at Kingston University near London, funded by the European Space Agency, is aimed at getting the robot to Mars by 2011. "Even though an actual mission to Mars is still many years away, the new vehicle could prove crucial in helping to determine the type of survival equipment needed in the future," Alex Ellery, research team leader, told AFP. The robot, named Endurance, is designed to rove the planet's surface using solar power, drilling beneath the surface to search for traces of life in the form of microbes. Read the full article at http://www.spacedaily.com/2003/030502172753.l8zd0na3.html. ________________________________________________________________________ PLoS BIOLOGY NOW OPEN TO ACCEPT PAPERS Public Library of Science release 2 May 2003 The Public Library of Science initiative, an international grass-roots organization of scientists, is launching its first open access journal. PLoS Biology will compete head-to head with the leading existing publications in biology, publishing the best peer-reviewed original research articles, timely essays, and other features. 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Your Journal * PLoS is a nonprofit organization founded and operated by scientists. * All editorial decisions made by members of our outstanding editorial board working in partnership with first-class professional editors. ________________________________________________________________________ DINNER WITH DARWIN From Astrobiology Magazine 4 May 2003 This featured "Dinner with..." series builds on the classic thought experiment: "Which 5 historical figures would you invite to dinner, and how would you seat them?" While the field of astrobiology historically rests on many "shoulders of giants"--too many for one dinner party, the Astrobiology Magazine has selected some initial candidates for our dinner party, and then asks them to introduce their area of expertise in a brief question and answer format. The answers are their own, as gleaned from some of their most famous, controversial, or seminal contributions to science. In many cases, the selection of commentary is driven by the curiosity to understand these great historical figures as one might imagine them as more modern characters, perhaps joining in on table talk or an informal interview. Tonight's dinner introduces Charles Darwin, voyager on the ship, H.M.S. Beagle, headed towards South America, as he seeks to understand the origin of species. Astrobiology Magazine [AM]: How did you first undertake your project? Charles Darwin [CD]: When on board H.M.S. Beagle, as naturalist, I was much struck with certain facts in the distribution of the inhabitants of South America, and in the geological relations of the present to the past inhabitants of that continent. These facts seemed to me to throw some light on the origin of species--that mystery of mysteries. Who can explain why one species ranges widely and is very numerous, and why another allied species has a narrow range and is rare? Yet these relations are of the highest importance, for they determine the present welfare, and, as I believe, the future success and modification of every inhabitant of this world. AM: What have you found out so far? CD: The view that each species has been independently created--is erroneous. I am fully convinced that species are not immutable; but that those belonging to what are called the same genera are lineal descendants of some other and generally extinct species, in the same manner as the acknowledged varieties of any one species are the descendants of that species. Furthermore, I am convinced that natural selection has been the main but not exclusive means of modification. AM: What do you mean, by natural selection? CD: The theory of natural selection is grounded on the belief that each new variety, and ultimately each new species, is produced and maintained by having some advantage over those with which it comes into competition; and the consequent extinction of less-favored forms almost inevitably follows. AM: Nature as a competition? But what about a parasite--something that is very dependent and not competing? CD: In the case of the mistletoe, which draws its nourishment from certain trees, which has seeds that must be transported by certain birds, and which has flowers with separate sexes absolutely requiring the agency of certain insects to bring pollen from one flower to the other, it is equally preposterous to account for the structure of this parasite, with its relations to several distinct organic beings, by the effects of external conditions, or of habit, or of the volition of the plant itself. There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved. AM: So after studying the classic mammalian debates, which do you favor: "nature or nurture" as the more important to a species chances to succeed? CD: No breeder doubts how strong is the tendency to inheritance: like produces like... Perhaps the correct way of viewing the whole subject, would be, to look at the inheritance of every character whatever as the rule, and non- inheritance as the anomaly. Once you accept variability as a rule, the question of selection, relative fertility and survival comes up. So why did you choose to begin most of your theory of "natural" selection with the list of challenges to doing "unnatural" selection, either by breeders or domesticators? The principle of selection I find distinctly given in an ancient Chinese encyclopedia. Explicit rules are laid down by some of the Roman classical writers. From passages in Genesis, it is clear that the color of domestic animals was at that early period attended to. When we compare the many breeds of dogs, each good for man in very different ways; when we compare the game-cock, so pertinacious in battle, with other breeds so little quarrelsome, with "everlasting layers" which never desire to sit, and with the bantam so small and elegant; when we compare the host of agricultural, culinary, orchard, and flower-garden races of plants, most useful to man at different seasons and for different purposes, or so beautiful in his eyes, we must, I think, look further than to mere variability. We cannot suppose that all the breeds were suddenly produced as perfect and as useful as we now see them; indeed, in several cases, we know that this has not been their history. The key is man's power of accumulative selection: nature gives successive variations; man adds them up in certain directions useful to him. In this sense he may be said to make for himself useful breeds. AM: So humans have given direction to an otherwise directionless evolution? CD: The great power of this principle of selection is not hypothetical... By a similar process of selection, and by careful training, the whole body of English racehorses has come to surpass in fleetness and size the parent Arab stock. Breeders habitually speak of an animal's organization as something quite plastic, which they can model almost as they please. But it is very far from true that the principle is a modern discovery. AM: Such changes are that dramatic, modifying to a new species after only after a few generations? CD: It has taken centuries or thousands of years to improve or modify most of our plants up to their present standard of usefulness to man. In a vast number of cases we cannot recognize, and therefore do not know, the wild parent-stocks of the plants which have been longest cultivated in our flower and kitchen gardens. That most skilful breeder, Sir John Sebright, used to say, with respect to pigeons, that "he would produce any given feather in three years, but it would take him six years to obtain head and beak." AM: You have experimented with pigeons yourself, correct? CD: Believing that it is always best to study some special group, I have, after deliberation, taken up domestic pigeons. I have kept every breed which I could purchase or obtain Pigeons can be mated for life, and this is a great convenience to the fancier, for thus many races may be kept true, though mingled in the same aviary; and this circumstance must have largely favored the improvement and formation of new breeds. Pigeons, I may add, can be propagated in great numbers and at a very quick rate. AM: Doesn't the breeder's art presume a diverse stock of choices to select? This doesn't seem to answer the question of how the diversity originates in the wild, as say the environmental pressures change. CD: Man can hardly select, or only with much difficulty, any deviation of structure excepting such as is externally visible; and indeed he rarely cares for what is internal. He can never act by selection, excepting on variations which are first given to him in some slight degree by nature. I think these views further explain what has sometimes been noticed-- namely that we know nothing about the origin or history of any of our domestic breeds. But, in fact, a breed, like a dialect of a language, can hardly be said to have had a definite origin. AM: So one would have to look for examples in transition, where the history of say an organ or function was undergoing changes that a life of observation or records would reveal? Can you give us another example? CD: In some of the crabs the foot-stalk for the eye remains, though the eye is gone; the stand for the telescope is there, though the telescope with its glasses has been lost. So through use and disuse, advantage and disadvantage, all the many diverse species "evolve" towards a more robust variety? A kind of "ascent via family descent with modification" is sometimes referred to here, correct? Whatever the cause may be of each slight difference in the offspring from their parents--and a cause for each must exist--it is the steady accumulation, through natural selection, of such differences, when beneficial to the individual, that gives rise to all the more important modifications of structure, by which the innumerable beings on the face of this earth are enabled to struggle with each other, and the best adapted to survive. AM: So one shouldn't be surprised by missing gaps in the fossil record, and apparent jumps in evolution? CD: Extinction and natural selection will, as we have seen, go hand in hand. Representative species often meet and interlock; and as the one becomes rarer and rarer, the other becomes more and more frequent, till the one replaces the other. [But] why do we not now find closely- linking intermediate varieties? This difficulty for a long time quite confounded me. It has been asked by the opponents of such views as I hold, how, for instance, a land carnivorous animal could have been converted into one with aquatic habits; for how could the animal in its transitional state have subsisted? AM: What's your theory then? CD: I think such difficulties have very little weight. I can see no difficulty, more especially under changing conditions of life... by the accumulated effects of this process of natural selection, a perfect so- called flying squirrel was produced. A transitional species, the ground and tree dweller, converted in form to its better aerial life, correct? Or the flying lemur. AM: Do these same transition play from air to land? CD: If about a dozen genera of birds had become extinct or were unknown, who would have ventured to have surmised that birds might have existed which used wings solely as flappers, like the logger-headed duck; as fins in the water and front legs on the land, like the penguin; as sails, like the ostrich; and functionally for no purpose, like the Apteryx. They serve, at least, to show what diversified means of transition are possible. When we see any structure highly perfected for any particular habit, as the wings of a bird for flight, we should bear in mind that animals displaying early transitional grades of the structure will seldom continue to exist to the present day, for they will have been supplanted by the very process of perfection through natural selection. AM: But I thought variation in itself made for highly adapted habits, and so do you think perfection as a fewer, better species seems a biological risk in itself? CD: He who believes that each being has been created as we now see it, must occasionally have felt surprise when he has met with an animal having habits and structure not at all in agreement. Can a more striking instance of adaptation be given than that of a woodpecker for climbing trees and for seizing insects in the chinks of the bark? Yet in North America there are woodpeckers which feed largely on fruit, and others with elongated wings which chase insects on the wing. It is difficult to tell, and immaterial for us, whether habits generally change first and structure afterwards; or whether slight modifications of structure lead to changed habits; both probably often change almost simultaneously. AM: That seems like a naturalist view where there is considerable waste? CD: He who believes in the struggle for existence and in the principle of natural selection, will acknowledge that every organic being is constantly endeavoring to increase in numbers; and that if any one being vary ever so little, either in habits or structure, and thus gain an advantage over some other inhabitant of the country, it will seize on the place of that inhabitant, however different it may be from its own place. There should be woodpeckers where not a tree grows. Read the original article at http://www.astrobio.net/news/article450.html. ________________________________________________________________________ PHOTOSYNTHESIS IN THE ABYSS By Stephen Hart From Astrobiolgy Magazine 5 May 2003 Deep-sea hydrothermal vents, with their black smokers, six-foot red tube worms and strange pale crabs and clams have become common features of biology textbooks, mainstream magazines, newspapers and TV nature shows. So has the understanding that these thriving communities depend not on green organisms using the Sun's light as a source of energy, but on bacteria and archaea that break down energy-rich chemicals spewing out of the sea floor along with the 350-degree C (662-degree F) vent water. For more than a decade after the discovery of hydrothermal vent communities in 1977, researchers found no biological evidence of light at vents. But in 1989, Cindy Van Dover, now at The College of William and Mary in Williamsburg, Virginia, began publishing studies of a small eyeless shrimp, Rimicaris exoculata, collected from vent fields in the mid-Atlantic. To their surprise, Van Dover and colleagues found that a patch of tissue on the shrimp's back contained some of the same pigments found in animal eyes. Calculations showed that the shrimp should be able to detect extremely faint light. Last year more biological evidence turned up. Robert Jinks and colleagues reported in the November 2002 Nature their studies of a crab with normal eyes as a larva, but nothing more than naked retinas as a vent-dwelling adult. As with the vent shrimp, these crabs cannot see images, but can detect light. A crazy idea Where there's light, there's a resource an organism can exploit, using the light energy to form energy-rich molecules--in other words, photosynthesis--or so Van Dover and colleagues proposed. In February 2003, Robert Blankenship, a photosynthesis expert at Arizona State University, added one more organism to the list of vent light users. He reported to the NASA Astrobiology Institute general meeting the results of a search for photosynthetic organisms that he, Van Dover, Jörg Overmann and others carried out during dives to two vent sites in the Pacific. "The question that one immediately asks is, 'Why are you looking for photosynthetic organisms in the deep ocean?' Because it seems to be sort of a crazy idea. And in fact, it took us quite some time to convince NASA and NSF to support this work," Blankenship says. Even clear ocean water filters out all of the Sun's light by about 200 meters [650 feet] depth. "But fortunately, the story has a happy ending," Blankenship says. Using an automated underwater sampling tool, the team sampled water in the plume of a black smoker in a vent field off the coast of Costa Rica nicknamed Nine North (9° north latitude). Back on the mother ship, Blankenship tested the water with special food, or medium, for a type of bacteria called green sulfur bacteria. "These green sulfur bacteria represent a group of very specialized bacteria," he says. Using a medium for green sulfur bacteria wasn't a wild guess. Jörg Overmann, at the University of Munich, had previously found green sulfur bacteria deep in the Black Sea. The deep, dark Black Sea Jörg Overmann has studied green sulfur bacteria growing deep in the cloudy Black Sea since 1988. The first hints that some kind of photosynthetic bacteria grew that deep and dark were traces of the light-capturing chemical bacteriochlorophyll detected by a US-Turkish expedition at about 80 meters [about 260 feet]. From samples of the water brought back by an expedition member, Overmann and colleagues conducted the first analysis of the bacteria. "At that point, we did not have any molecular data and could not determine the exact composition of the bacterial community," he says. "Photosynthetic activity of the natural samples could not be demonstrated. Also, it remained entirely unclear which light intensities are available in the natural habitat of these green sulfur bacteria." In December 2001, Overmann had another chance to sample in the Black Sea. "At this occasion, green sulfur bacteria were detected at a depth of 100 m (330 feet), even deeper than before." This time, Overmann was able to grow the bacteria in the lab and learn more about its identity: a member of the green sulfur bacteria usually found in the oxygen- starved waters of estuaries. In the Black Sea, the Sun remains only the light source for which Overmann sees any evidence. Even with the heavy filtering of the 100 meters (330 feet) of murky water, a tiny amount of visible light remains. In this environment, the bacteria must gather light with great efficiency. A single molecule of bacteriochlorophyll receives a single photon only about once every 8 hours. Blankenship says of the Black Sea bacteria "These guys are really scrounging for every photon that is there. So in a way it makes sense that that might be the sort of organisms we would find down there at the vents." Some bacteria are opportunists. They switch between energy sources. If there's enough light, they carry on photosynthesis to make their own food. If not, they eat whatever food is available in the environment. But for green sulfur bacteria, using light to make food is not an option. They can't live without light. Where's the light? Any substance whose temperature is above absolute zero (minus 273°C, minus 460°F]) emits some infrared light, called black body radiation. The hotter the substance, the more black body radiation, and the shorter the wavelength of the light emitted. If the substance is hot enough, the wavelengths get short enough to become red visible light. You can see the process by switching on an ordinary electric stove. As soon as the element receives power, black body radiation begins to increase, albeit at wavelengths human eyes cannot see. But after a short time, the element begins to glow a dull red, then a brighter red. Hydrothermal vent water also emits light, mostly in the infrared, and biologists supposed that the vent shrimp detected that light, perhaps to stay near the vent, where they could find food, perhaps to avoid getting too close. The bacteria use near-infrared light, with wavelengths almost into the range of visible red light, to carry on photosynthesis. Geophysicist Sheri N. White, now at the Monterey Bay Aquarium Research Institute, has measured the light at hydrothermal vents using a specialized camera similar to today's digital still cameras. These devices use charge coupled devices (CCDs) instead of film to record even a few photons per square centimeter of CCD. In research done in collaboration with Van Dover and others, White detected the expected infrared radiation. But she also found visible light, albeit dimmer than we can see. The visible light may arise from chemical reactions, the formation and breaking of mineral crystals and from bubble formation. "So in all vents you see this black body radiation at the long [far red to near infrared] wavelengths. But at some of them you see white light in the visible region," White says. In other vents, particular colors peak. Measurements of visible light from hydrothermal vents put the intensity at about a hundred to a million times dimmer than the light in the Black Sea, depending on which wavelengths are included. "Now how do these organisms get by on such low light intensities?" Blankenship asks. "They have this wonderful device called a chlorosome." Like a molecular satellite dish, Blankenship says, the chlorosome funnels photons to the molecular machinery that begins the work of storing light energy in the chemical bonds of food molecules. The chlorosome of vent-dwelling green sulfur bacteria makes them the world champions at garnering photons. (Overmann's green sulfur bacterium from the Black Sea held the previous record.) It's unlikely that any other organism that depends on light could get by on fewer photons. What's next? Green sulfur bacteria, though common in estuaries, have never been seen before in the open ocean, Blankenship says. Analysis of the new organism's RNA shows it to be a new species, a close cousin to common estuary green sulfur bacteria, and a close cousin to Overmann's Black Sea bacteria. Because it's a clearly a new species, it can't be a sampling contaminant, Blankenship says. But how long ago the bacteria's ancestors relocated from higher up in the ocean, settling in a low- oxygen niche near a vent remains an open question. "There are a lot of unanswered questions," Blankenship says. "One of the things we're working on right now is to try to look for independent evidence of these organisms using other techniques." Members of the international team are trying to analyze the RNA and DNA in the whole samples they brought back to the lab, a process called environmental PCR, which can detect new organisms even when they can't be grown in the lab. "So far we haven't had too much success with that," Blankenship admits, "but we're just getting going." "One of the best ways of detecting these things is with their characteristic fluorescence emission." By shining a particular wavelength of light on the bacteria, special instruments can detect the fluorescent glow of their particular photosynthetic pigments. The technical challenge, Blankenship says, is to build an instrument the researchers can put into the water at the hydrothermal vent to measure the fluorescent glow at very close range. Finally, Blankenship's group wants to measure how sensitive the new green fluorescent bacteria are to oxygen. All known green sulfur bacteria die in the presence of oxygen. But at vents, the plume of moving water mixes oxygen-containing water with oxygen-free water. A perfectly oxygen-free environment might be hard to find. Perhaps, in addition to adapting to extremely low light, this newly discovered species has also found a way to tolerate small amounts of oxygen. Read the original article at http://www.astrobio.net/news/article451.html. ________________________________________________________________________ NEW ADDITIONS TO THE ASTROBIOLOGY INDEX By David J. Thomas http://www.lyon.edu/webdata/users/dthomas/astrobiology/astrobiology.html 5 May 2003 Astrobiology, exobiology and terraformation articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_articles1. html Agence France-Presse, 2003. Tank-inspired robot set to hunt microbes on Mars. SpaceDaily. Terrestrial extreme environments articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_articles2. html S. Hart, 2003. Photosynthesis in the abyss. Astrobiology Magazine. Human space exploration and microgravity effects articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_articles3. html SpaceDaily, 2003. Moon Society and Artemis Society endorse Space Settlement Initiative. SpaceDaily. Search for extraterrestrial intelligence (SETI) articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_articles4. html S. Shostak, 2003. Arecibo diaries (5): the romance, drama and normality of the observatory. Space.com. Evolutionary biology and chemistry articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_articles5. html Astrobiology Magazine, 2003. Dinner with Darwin. Astrobiology Magazine. Planetary protection articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_articles6. html M. S. Race, 2003. Planetary protection: an integral part of mission preparations. Space.com. Astrobiology and extreme environments book list http://www.lyon.edu/webdata/users/dthomas/astrobiology/astrobiology_book s.htm C. S. Cockell and A. R. Blaustein (eds.), 2001. Ecosystems, Evolution and Ultraviolet Radiation. Springer Verlag, Berlin. C. S. Cockell, 2003. Impossible Extinction: Natural Catastrophes and the Supremacy of the Microbial World. Cambridge University Press, Cambridge. R. Lorenz and J. Mitton, 2002. Lifting Titan's Veil: Exploring the Giant Moon of Saturn. Cambridge University Press, Cambridge. L. Margulis, D. Sagan and N. Eldredge, 1995. What is life? Simon & Schuster, New York. L. Margulis and D. Sagan, 2002. Acquiring Genomes: A Theory of the Origins of Species. Basic Books, New York. ________________________________________________________________________ CONTINUING COVERAGE OF THE COLUMBIA DISASTER By David J. Thomas 5 May 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/04/29/sprj.colu.shuttle.investigation .ap/index.html http://www.cnn.com/2003/TECH/space/04/30/shuttle.worms.ap/index.html http://www.space.com/missionlaunches/sts107_caib_030429.html http://www.space.com/missionlaunches/space_congress_030430.html http://www.space.com/missionlaunches/sts107_reentry_030501.html http://www.space.com/missionlaunches/sts107_worms_030501.html http://www.spacedaily.com/2003/030502001910.srseylrv.html http://spaceflightnow.com/shuttle/sts107/030429breach/ ________________________________________________________________________ CASSINI SIGNIFICANT EVENTS NASA/JPL release 24-30 April 2003 The most recent spacecraft telemetry was acquired from the Canberra tracking station on Wednesday, April 30. 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. April 26th marked the 5th anniversary of Cassini's first Venus flyby. Cassini is using a Venus-Venus-Earth- Jupiter trajectory. Each flyby provides a gravity assist that cumulatively will enable Cassini to reach Saturn in 2004. The Command and Data Subsystem (CDS) Flight Software (FSW) checkout concluded this week with a successful optical navigation (OPNAV) test. Final activities for C36 included a reaction wheel assembly momentum unload, and uplink of the C37 background sequence. The completion of the optical navigation test marks the conclusion of the engineering flight software checkout period. Both the Attitude Control and Command and Data subsystems have successfully demonstrated the full suite of capabilities afforded by the new software that will be used throughout orbital operations. C37 began execution late Monday night. Initial activities included loading of Imaging Science Subsystem (ISS), Ultraviolet Imaging Spectrograph (UVIS), and Radio and Plasma Wave Science (RPWS) instrument expanded blocks from the background sequence, RPWS high-rate observations, an RPWS high frequency receiver calibration, and clearing of the attitude control high water marks. At the end of this week the spacecraft transitioned to reaction wheels in preparation for trajectory correction maneuver 19. Optical navigation data from this weeks test have been processed by the Multimission Image Processing Laboratory (MIPL), including 18 Narrow Angle Camera (NAC) and nine Wide Angle Camera (WAC) images. The Navigation team has reviewed the data and reported that pointing was very good (within about five or six NAC pixels of the target) and that the exposures on 11th magnitude stars are good. Mission Planning and Science Planning held a kick off meeting for the implementation of the science operations plan for tour sequences tour sequences S7/S8 this week, along with a project briefing for the cruise sequence C39. An Archive Design Peer Review of the Cosmic Dust Analyzer (CDA), ISS, Radio Science Subsystem (RSS), and Visual and Infrared Mapping Spectrometer (VIMS) instrument team archive plans was held this week. Members of the Planetary Data System, instrument team representatives, and Instrument Operations personnel attended. A Software Review Certification Requirement meeting was held for Composite Infrared Spectrometer FSW version 2.0.1. The software is due to be uplinked to the spacecraft in late May. MIPL delivered an engineering version of the remote constraint checker tools to the ISS and VIMS science teams. The software will be used for validation of Instrument Operations Interface (IOI) files prior to delivery to IO. These tools allow a remote site to automatically deliver preliminary IOI files to MIPL, have them error/constraint checked there, and have the results returned to the remote site. During operations this will enable instrument teams to deliver error-free IOI files. Cassini is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, CA, manages the Cassini mission for NASA's Office of Space Science, Washington, DC. ________________________________________________________________________ ESA'S MARS EXPRESS READY FOR LAUNCH ESA release 28-2003 5 May 2003 Just before midnight on 2 June (23:45 local time, 19:45 CEST) a Soyuz rocket operated by Starsem will lift off from the Baikonur Cosmodrome, and Mars Express will be on its way. The spacecraft was given the green light to launch following completion of a successful flight readiness review on 3 May. The Mars Express launch window opens on 23 May and lasts only four weeks. However, just before the spacecraft was due to leave Toulouse, France, for its trip to Baikonur in Kazakhstan, engineers discovered a fault in one of the electronics modules. "Of course, it was the most difficult box to remove from the spacecraft," says with a smile Rudi Schmidt, Mars Express Project Manager. In view of the estimated time needed to correct the fault, the launch date was initially put back from 23 May to 6 June, still within the launch window. However, thanks to the skill and dedication of the engineering team, the job was completed sooner than expected and the launch date was brought forward. Mars Express is currently being fuelled, an operation that takes about a week. It will then be attached to Fregat, the Soyuz upper stage rocket booster, and mated with the Soyuz rocket. The whole system will be rolled out to the pad four days before launch. The journey to Mars will take six months and the spacecraft should enter its martian orbit on 26 December. Europe's contribution to the exploration of the Red Planet will begin soon. Contact: ESA Communication Department Media Relations Office Paris, France Phone: +33(0)15369 7155 Fax: +33(0)1 5369 7690 Live images of Mars Express are available on the ESA Science web site (http://sci2.esa.int/spacecam/marsexpress.htm). For more information about the Mars Express launch campaign, visit http://www.esa.int/marsexpresslaunch. For more information about the ESA Science Program, visit http://sci.esa.int. For more information about ESA, visit http://www.esa.int. For more information about Starsem, visit: http://www.starsem.com. Read the original news release at http://sci.esa.int/content/news/index.cfm?aid=9&cid=32&oid=32211. ________________________________________________________________________ MARS GLOBAL SURVEYOR IMAGES NASA/JPL/MSSS release 26 April - 3 May 2003 The following new images taken by the Mars Orbiter Camera (MOC) on the Mars Global Surveyor spacecraft are now available: Layers in 8°N, 7°W Crater (Released 26 April 2003) http://www.msss.com/mars_images/moc/2003/04/26/index.html Russell Dune Gullies (Released 27 April 2003) http://www.msss.com/mars_images/moc/2003/04/27/index.html Aram and Iani Chaos (Released 28 April 2003) http://www.msss.com/mars_images/moc/2003/04/28/index.html Boulder Ring (Released 29 April 2003) http://www.msss.com/mars_images/moc/2003/04/29/index.html Layers near Juventae Chasma (Released 30 April 2003) http://www.msss.com/mars_images/moc/2003/04/30/index.html Meridiani Cliffs and Buttes (Released 1 May 2003) http://www.msss.com/mars_images/moc/2003/05/01/index.html Sedimentary Rock Layers (Released 2 May 2003) http://www.msss.com/mars_images/moc/2003/05/02/index.html Frosty North Polar Layers (Released 3 May 2003) http://www.msss.com/mars_images/moc/2003/05/03/index.html All of the Mars Global Surveyor images are archived at http://www.msss.com/mars_images/moc/index.html. Mars Global Surveyor was launched in November 1996 and has been in Mars orbit since September 1997. It began its primary mapping mission on March 8, 1999. Mars Global Surveyor is the first mission in a long-term program of Mars exploration known as the Mars Surveyor Program that is managed by JPL for NASA's Office of Space Science, Washington, DC. Malin Space Science Systems (MSSS) and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO. ________________________________________________________________________ MARS ODYSSEY THEMIS IMAGES NASA/JPL/ASU release 28 April - 2 May 2003 Lycus Sulci (Released 28 April 2003) http://themis.la.asu.edu/zoom-20030428a.html Western Amazonis flow features and crater interaction (Released 30 April 2003) http://themis.la.asu.edu/zoom-20030430a.html Eroded Ejecta (Released 1 May 2003) http://themis.la.asu.edu/zoom-20030501a.html Martian Kanji (Released 2 May 2003) http://themis.la.asu.edu/zoom-20030502a.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. ________________________________________________________________________ End Marsbugs, Volume 10, Number 18.