MARSBUGS: The Electronic Astrobiology Newsletter Volume 9, Number 32, 2 September 2002. 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 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) TRACKING THE PATH OF GREEN SLIME By Leslie Mullen 2) SETI@HOME SPELLS OUT NEW PLANS From Sky & Telescope 3) NEW ADDITIONS TO THE ASTROBIOLOGY INDEX By David J. Thomas 4) CASSINI SIGNIFICANT EVENTS NASA/JPL release 5) NASA APPOINTS CONTOUR MISSION INVESTIGATION TEAM NASA HQ release 02-161 6) INTERNATIONAL SPACE STATION SCIENCE OPERATIONS STATUS REPORT NASA/MSFC release 02-210 7) MARS ODYSSEY THEMIS IMAGES NASA/JPL/ASU release 8) STARDUST STATUS REPORT NASA/JPL release _____________________________________________________________________ TRACKING THE PATH OF GREEN SLIME By Leslie Mullen From Astrobiology Magazine 28 August 2002 Most life on Earth owes its existence to tiny organisms called cyanobacteria. These primitive bacteria gave us oxygen for the atmosphere and a protective ozone layer, and they led to the development of all the green plants in the world today. "Cyanobacteria are the microbial heroes of Earth history," says Andrew Knoll, a professor of evolutionary biology at Harvard University. "They are the inventors of 'green plant' photosynthesis and the ultimate source of breathable air." Of course, when cyanobacteria first appeared, the other life forms on Earth weren't too happy about it. It was as though an ill-mannered cousin showed up with a big stinky cigar, blowing smoke right in their faces. Only in this case, the smoke was a poisonous gas known as oxygen. Untold numbers of organisms were wiped out as cyanobacteria released oxygen into the atmosphere. If they were lucky, the stressed organisms managed to hide away in places where oxygen couldn't reach--deep down in anoxic mud or in the cracks and crevices of hydrothermal vents under the sea. The offspring of these survivors can still be found living in these places today. Cyanobacteria, too, are still around today. They can be found everywhere from the surface of the oceans to underneath rocks in the desert. They can live in bright light or low light, in salt water and fresh, in extreme cold or heat, with oxygen or without it. In fact, cyanobacteria are so widespread that J. William Schopf, professor of paleobiology at UCLA, calls cyanobacteria, "evolution's most successful ecologic generalists." Not only can cyanobacteria live just about anywhere, but they've also managed to survive throughout much of Earth's biotic history. Whatever ecological catastrophes fate has thrown at the Earth--be it another Ice Age, a large asteroid impact, or changes in the atmosphere--through it all cyanobacteria have survived. "Like fantastic aliens of a class B movie," Schopf writes in his book, Cradle of Life, "they've proven impossible to wipe out, surviving on and on as life around them has gone extinct." And, even more extraordinarily, cyanobacteria appear to have survived relatively unchanged. Schopf says that they do not look appreciably different from the cyanobacteria of two billion years ago. How could cyanobacteria be so untouched by the processes of evolution, when in the same amount of time the rest of life evolved from a single celled organism to the vast range of forms we see today, including our own human species? As it turns out, different organisms experience different rates of evolution. Some organisms, like insects, evolve quickly. That's why pesticides stop being effective after a certain period of time--those that can tolerate the pesticide survive to breed, and before you know it all the offspring are immune. Others, like cyanobacteria, evolve more slowly. Another reason cyanobacteria have been able to get away with so little evolutionary change is because of their ability to live almost anywhere. Evolution is often propelled by the need to adapt to environmental change. In addition, cyanobacteria reproduce non- sexually. The vast numbers of possible genetic combinations that we see in sexually reproducing organisms just don't occur with cyanobacteria. Evolution hasn't completely by-passed cyanobacteria. There is evidence that some modern cyanobacteria are more sophisticated than their ancestors, forming communities with a range of adaptations to maximize their share of the available light and nutrients. But because cyanobacteria fossils look so similar to modern cyanobacteria, this suggests that some forms of cyanobacteria have changed very little over the years. This makes tracking their history in the fossil record difficult. Scientists would dearly like to know, for example, when cyanobacteria first came on the scene. In 1993, Schopf made headlines when he claimed to find the earliest known fossilized life. These structures, which he described as "cyanobacterium-like," were found in 3.5 billion-year-old chert (a type of silica rock) from Western Australia. Since his discovery, these ancient structures are often cited as the oldest fossilized life on Earth. However, Schopf's finding may not be as definite as the textbooks and news reports would have you believe. Some scientists contend that the shapes found by Schopf are not cyanobacteria, or even fossilized life forms at all. Martin Brasier of Oxford University leads the opposition against Schopf's claims. Brasier says that rather than being biological fossils, these structures are chemical artifacts formed from hydrothermally-heated graphite. The debate rages on, and many scientists are conducting their own studies of the enigmatic structures in an effort to find the truth. Another controversial topic in the debate over cyanobacteria is the existence of Archaean stromatolites. These layered rock formations are formed by cyanobacteria. The bacteria live in a colonial layer called a "microbial mat." When too many minerals and sediments became trapped in the sticky mat, sunlight can no longer penetrate and photosynthesis becomes impossible. The cyanobacteria then migrate up, creating a new mat layer on top of the old. This process occurs again and again, creating multiple sediment layers over time. The existence of stromatolites dating back to nearly 3.5 billion years ago suggests that cyanobacteria were hard at work during the Archaean era. But not all stromatolites are formed by cyanobacteria; natural geological processes can build similar structures. Some have argued, therefore, that the ancient rock structures were formed by chemical precipitation or by the deformation of soft sediments. At the time of this writing, microfossils from the 2.2 billion-year- old Gunflint Chert--found in the Great Lakes region of the United States--are the earliest uncontested evidence for cyanobacteria. "The origins of cyanobacteria are still mysterious," says Roger Summons, a professor of biogeochemistry and geobiology at MIT. "However, because the genomes and the biochemistry of today's cyanobacteria preserve some kind of evolutionary record, we can learn more about their earlier forms." Understanding when cyanobacteria first appeared would not only help answer many questions about early life, it also would help pin down when oxygen began to be an important part of the environment. But even if cyanobacteria did form the Archaean stromatolites, they might not have been producing oxygen. In order to develop oxygen-producing photosynthesis, cyanobacteria had to undergo a series of evolutionary steps. A modern-day photosynthetic cell undergoes two simultaneous reactions, both of which rely on a separate kind of protein. Photosystem I protein molecules use the trapped energy in sunlight [to produce chemical energy in the form of ATP]. This provides [energy to make] food in the form of carbohydrates, lipids, proteins and nucleic acids--the building blocks of life. Photosystem II protein molecules use light energy to split water into hydrogen ions and oxygen molecules. [The hydrogen ions are used, along with the ATP, to make food molecules]. But the first photosynthetic organisms didn't produce oxygen. The most ancient photosynthetic bacterial species are purple and green bacteria. Purple bacteria and green, non-sulfur bacteria rely on Photosystem II for energy, while green sulfur bacteria use Photosystem I. Cyanobacteria, algae and plants use both Photosystem I and II, and it is generally believed that the two Photosystems arose from a single evolutionary ancestor. However, another possibility is that there may have been some gene swapping between the two photosynthetic groups. Called "lateral gene transfer," this type of gene sharing may have been common in life's early days. Many believe that this could have been the means by which cyanobacteria gained access to the genes necessary for both Photosystems. Another technique of early evolution is that cells could absorb other cells in an act of symbiosis. Rather than digest the absorbed cell as food, it would become a part of the devouring cell's inner machinery. [A cyanobacterium], it is thought, was absorbed by an early eukaryotic cell (a cell with a nucleus). The absorbed cyanobacterium became a chloroplast, the structure that is responsible for photosynthesis in modern plants. "Cyanobacteria evolved further to be the chloroplasts of other photosynthetic organisms, particularly algae and the green plants," says Summons. "Thus, cyanobacteria may be just 'green slime' to some, but they are the foundations of the ecosystems of all complex life." What's next Schopf and his colleagues are intensely studying the 3.5 billion- year-old structures from the Australia chert. They are currently doing laser-Raman spectroscopy, atomic force microscopy, and ion microprobe carbon isotopic analyses to try to find out whether the structures are cyanobacteria. Summons, meanwhile, is conducting studies of the molecular biomarkers of modern cyanobacteria with his colleague Kai Hinrichs at the Woods Hole Oceanographic Institution (WHOI). By working with biologists who are experts on cyanobacterial occurrence, culturing, and genetics--such as John Waterbury (WHOI), Penny Chisholm (MIT), and Linda Jahnke (NASA)--they hope to develop molecular signatures for cyanobacterial productivity in the oceans. Summons believes these studies will lead to new methods for recognizing cyanobacteria in the sedimentary record, and perhaps trace them back to their earliest ancestors. Additional information on this article is available at http://www.astrobio.net/news/article259.html. _____________________________________________________________________ SETI@HOME SPELLS OUT NEW PLANS From Sky & Telescope 30 August 2002 More than three years after it began, the SETI@home project has announced plans to expand its hunt for radio signals coming from intelligent civilizations among the stars. The biggest advance is that SETI@home II should gather about 10 or 15 times more radio data per day, on average, than now gets recorded at Arecibo (the new system will span a wider frequency range and listen to several spots on the sky at once). This means that at long last, the project will have enough raw data to keep all its volunteers productively busy. Right now there are more than twice as many volunteers as are needed to do the current job; at least half of them are being sent duplicate data as make-work. Get the full story at http://SkyandTelescope.com/news/current/article_724_1.asp. _____________________________________________________________________ NEW ADDITIONS TO THE ASTROBIOLOGY INDEX By David J. Thomas http://www.lyon.edu/webdata/users/dthomas/astrobiology/astrobiology.h tml 2 September 2002 Astrobiology, exobiology and terraformation articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_article s1.html S. Shostak, 2002. The meaning of life. Space.com. Terrestrial extreme environments articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_article s2.html U. Nübel, M. M. Bateson, V. Vandieken, A. Wieland, M. Kühl and D. M. Ward, 2002. Microscopic examination of distribution and phenotypic properties of phylogenetically diverse Chloroflexaceae-related bacteria in hot spring microbial mats. Applied and Environmental Microbiology, 68(9):4593-4603. Evolutionary biology and chemistry articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_article s5.html L. Mullen, 2002. Tracking the path of green slime. Astrobiology Magazine. _____________________________________________________________________ CASSINI SIGNIFICANT EVENTS NASA/JPL release 22-28 August 2002 The most recent spacecraft telemetry was acquired from the Goldstone tracking station on Tuesday, August 27. The Cassini spacecraft is in an excellent state of health and is operating normally. Information on the present position and speed of the Cassini spacecraft may be found on the "Present Position" web page located at http://saturn.jpl.nasa.gov/cassini/english/where/. On-board activities this week included clearing of the ACS high water marks, Radio and Plasma Wave Science High Frequency Receiver calibrations, uplink of the Cassini Plasma Spectrometer gain parameter update, and execution of an Imaging Science Subsystem flight software checkout. This version of the flight software enables some tests to further characterize the long-standing 2-hertz noise problem that causes subtle striping in images. Analysis of the latest data will begin next week. A wrap-up meeting was held after the successful completion of the first Tour Science Planning Team process for S09/S10. Advance science planning for 5% of the Tour is done! The Science Planning Manager commended all participants for their hard work in achieving this first milestone. The Magnetospheric Imaging Instrument (MIMI) science team is finalizing archive product definitions for their instrument data based on a meeting between a representative from the Plasma Physics Interactions node of the Planetary Data System and staff from Fundamental Technologies, the company that is developing the MIMI archive plan. MIMI is preparing for a peer review of their archive design in the November-December timeframe. The Visible and Infrared Mapping Spectrometer (VIMS) instrument flight software version 5.1 has been delivered to the Project Software Library. Regression testing was run using the VIMS Electronic Ground Support Equipment breadboard in the Instrument Operations clean room, with additional testing performed in the Integrated Test Laboratory. Test results are being analyzed in preparation for the upcoming Delivery Coordination Meeting. The Radio Science receiver was used to support the search for the CONTOUR spacecraft. No signal was detected. A Cassini Information Management System 2.3.1 patch delivery took place to fix two minor bugs. In response to an action item from the PSG meeting held in June, System Engineering initiated twice weekly CIMS & Uplink Process Working Group meetings. The topic at this week's Cassini Design Team meeting was the End-to- End Tour Uplink System V&V activity planned for the C38 timeframe. The meeting described the testing planned, particularly the role of the remote sites. Mission Assurance attended a briefing for the new Software Development Requirements. These new requirements have been produced to incorporate CAN findings, ensure compliance with SEI's Software Capability Maturity Model Integration and provide one-stop shopping for software task managers. The new requirements are now applicable to all JPL Programs and Projects. Initial indications are that Cassini is compliant with the requirements and will not be impacted by the change. A joint JPL/Aerospace Risk Management Workshop was conducted at Aerospace Corporation this week. This was the third in a series of workshops being conducted to jointly evolve the Risk Management Process forward and establish some consistency within the industry. Cassini Mission Assurance led the development of the benchmarking group, which developed a list of companies / industries to benchmark as well as a candidate list of questions to be used. The next workshop is anticipated to occur at JPL within a month or so. Testing at the Emergency Control Center at Goldstone last Thursday was successful. Predicts were generated there, the antenna pointed, and a command loss timer reset was sent to Cassini. Only one minor item needs resolution. 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. _____________________________________________________________________ NASA APPOINTS CONTOUR MISSION INVESTIGATION TEAM NASA HQ release 02-161 26 August 2002 NASA Administrator Sean O'Keefe today announced that Chief Engineer Theron M. Bradley, Jr. will lead a team to investigate the apparent loss of the CONTOUR mission space probe. The investigation team will independently examine all aspects of the CONTOUR mission, which has been out of contact with controllers at the Johns Hopkins University Applied Physics Laboratory (APL), Laurel, MD, since a scheduled engine firing August 15. In May, Bradley joined the agency as Chief Engineer to provide independent technical review of NASA's programs and projects. He's a distinguished U.S. Navy engineer who was instrumental in the initial design of the nuclear propulsion plant for Nimitz class aircraft carriers and the advanced reactor design for Los Angeles class submarines. Bradley also served as a civilian with the U.S. Department of Energy and the Department of Defense in numerous leadership and management positions. The team will include a team of internal NASA investigators from space science, as well as other aerospace disciplines, and external experts with extensive experience in accident examinations. The group is expected to report its initial findings to NASA Headquarters in six to eight weeks. Among the team members selected to work with Bradley are retired Navy Admirals J. Paul Reason and Joseph Lopez. Admiral Reason is a member of NASA's Aerospace Safety Advisory Panel (ASAP). He's an aerospace consultant and former four-star Commander in Chief of the U.S. Navy's Atlantic Fleet. The ASAP was established by Congress in January 1967 after the Apollo 204 Command and Service Module spacecraft fire and is chartered to review, evaluate and advise on agency program activities, systems, procedures and management policies that contribute to risk, and to provide identification and assessment for the NASA Administrator. Admiral Lopez is one of the two flag officers in the U.S. Navy to achieve the rank of four-star admiral after direct commission from enlisted service. The retired admiral is the former commander of NATO forces in southern Europe and has played a leadership role in numerous accident investigations. He currently directs Global Government Operations as an executive with Houston-based KBR (Kellogg, Brown & Root). On August 15, CONTOUR's STAR 30 solid-propellant rocket motor was programmed to ignite at 4:49 AM EDT, giving CONTOUR enough boost to escape Earth's orbit. At that time, CONTOUR was about 140 miles above the Indian Ocean and out of radio contact with controllers. The CONTOUR mission operations team at APL expected to regain contact at approximately 5:35 AM EDT to confirm the burn, but NASA's Deep Space Network (DSN) antennas did not acquire a signal. Since then, there has been no contact with CONTOUR. Commands pre- programmed into the spacecraft's flight computer system, designed to instruct the spacecraft to try various alternate methods of contacting Earth when contact is lost, also have not worked to date. Images from a Spacewatch ground-based telescope at Kitt Peak, AZ, show three objects at the location where CONTOUR was predicted to be, images which may indicate the spacecraft has broken apart. Mission controllers at APL will continue listening for signals from the spacecraft periodically until early December, when CONTOUR will come into a more favorable angle for receiving a signal from Earth. CONTOUR is a Discovery-class mission to explore the nucleus of comets. The Principal Investigator is Dr. Joseph Veverka of Cornell University, Ithaca, NY, who selected APL to build the spacecraft and manage the mission for NASA. Additional information about CONTOUR is available on the Internet at http://www.contour2002.org. Contacts: Donald Savage/Bob Jacobs NASA Headquarters, Washington, DC Phone: 202-358-1547 x1600 Additional articles on this subject are available at: http://www.space.com/missionlaunches/contour_update_020826.html http://spacedaily.com/news/020826205326.drre2pin.html _____________________________________________________________________ INTERNATIONAL SPACE STATION SCIENCE OPERATIONS STATUS REPORT NASA/MSFC release 02-210 28 August 2002 Commander Valery Korzun wrapped up his Monday spacewalk with a lung function test on Tuesday to help learn whether the low pressure environment of his space suit has any effects on his lungs. Korzun conducted the Pulmonary Function in Flight (PuFF) experiment as part of an ongoing study of the effects of long-term spaceflight and spacewalks on crew lung function. The lung function tests are conducted on a regular monthly basis as well as before and after spacewalks. Each PuFF session consists of five lung function tests, which involve breathing cabin air through a measurement device. The focus is on measuring changes in the evenness of gas exchange in the lungs and on detecting changes in respiratory muscle strength that may result from long periods in microgravity. The experiment uses the Gas Analyzer System for Metabolic Analysis Physiology (GASMAP),located in the Human Research Facility rack, along with other equipment. The data are stored and later transmitted to the ground. PuFF research builds on research conducted during Spacelab missions during the last decade. Unlike Spacelab missions, Station missions are much longer and often involve more spacewalks by the crews. Spacewalks pose a risk of nitrogen bubble formation in the blood because the U.S. spacesuits operate at about 4.3 pounds of pressure per square inch, and the Russian spacesuits--used Monday--operate at about 5.7 psi, compared to normal atmospheric pressure on Earth and inside the Station of 14.7 psi. Scientists hope to find new ways to protect the health of future space travelers, and to gain a better understanding of the effects of gravity on the lungs on Earth. PuFF was developed by Dr. John West, of the University of California, San Diego, and is managed by NASA's Johnson Space Center in Houston. On Tuesday and Wednesday, selected members of the International Space Station crew continued to record their experiences for the Crew Interactions experiment. The experiment, which has been part of every Expedition since the Station became permanently occupied, will identify and characterize important interpersonal and cultural factors that may affect the performance of the crew and ground support personnel. The crew today conducted a battery of maintenance activities with the Advanced Astroculture experiment, collecting nutrient, condensation, and gas samples from the plant growth device as a way of getting a detailed look at the growth process of soybean plants growing inside. Crew Earth Observations photography subjects this week included: Kingman Reef and Palmyra Atoll in the Pacific, Amman, Jordan, Guagzhou and Xianggang, China, and Hurrican Fausto. On Friday, the crew is tentatively scheduled to turn on the Materials Science Glovebox and begin recovery procedures with the Solidification Using Baffle in Sealed Ampoule (SUBSA) experiment. Recovery work is a prelude to resuming research with SUBSA and the Glovebox. SUBSA is investigating manufacturing processes that could yield insights into semiconductor production on Earth. During the fifth SUBSA experiment recently, the quartz sample tube cracked and then broke during removal, leaving some small particles that have to be removed. The crew continued to conduct daily status checks on experiments and research equipment onboard during the past week. Automated experiments continuing to operate normally included the Materials International Space Station Experiment (MISSE), Protein Crystal Growth Single Thermal Enclosure System (PCG-STES), Advanced Astroculture (ADVASC), Microgravitiy Acceleration Measurement System (MAMS), and Space Acceleration Measurement System (SAMS). Completed science payloads for Expedition Five include: StelSys, Educational Payload Operations 5, Microencapsulation Electrostatic Processing (MEPS), and Zeolite Crystal Growth (ZCG). The Payload Operations Center at NASA's Marshall Space Flight Center in Huntsville, AL, manages all science research experiment operations aboard the International Space Station. The center is also home for coordination of the mission-planning work of a variety of international sources, all science payload deliveries and retrieval, and payload training and payload safety programs for the Station crew and all ground personnel. Contact: Steve Roy MSFC Media Relations Department Phone: 256-544-0034 E-mail: Steve.Roy@msfc.nasa.gov _____________________________________________________________________ MARS ODYSSEY THEMIS IMAGES NASA/JPL/ASU release 26-30 August 2002 Mars Odyssey has come out of solar conjunction and the THEMIS Image- of-the-Day has resumed. Trouvelot Crater Deposit (Released 26 August 2002 http://themis.la.asu.edu/zoom-20020826a.html Buried Crater (Released 27 August 2002) http://themis.la.asu.edu/zoom-20020827a.html Ares Vallis Polygons (Released 28 August 2002) http://themis.la.asu.edu/zoom-20020828a.html Tharsis Grooved Channel (Released 29 August 2002) http://themis.la.asu.edu/zoom-20020829a.html Kasei Vallis Streamlined Island (Released 30 August 2002) http://themis.la.asu.edu/zoom-20020830a.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 30 August 2002 There was one scheduled Deep Space Network (DSN) tracking pass in the past week and all subsystems are normal. A test of the Navigation Camera mirror was successfully completed to see if the mirror would stall, even at the lowest commandable rates for adjusting its angle. As expected, the mirror moved at all commanded rates, successfully completing another in-flight test of a capability that will be needed for tracking the nucleus of Comet Wild 2 in 2004. A software patch was successfully installed on the spacecraft for the Navigation Camera's pattern-matching and windowing code. This software searches for up to 11 bright objects in an image and then sends down only small windows around these bright objects, reducing the transmitted data by more than 1,000-fold for that image. An alignment calibration of the Navigation Camera's mirror will be performed next week using the new software capability. Windowed images will be taken at 10-degree increments throughout the 200 degree range of mirror pointing capability. For more information on the Stardust mission--the first ever comet sample return mission--please visit the Stardust home page at http://stardust.jpl.nasa.gov. _____________________________________________________________________ End Marsbugs, Volume 9, Number 32.