MARSBUGS: The Electronic Astrobiology Newsletter Volume 6, Number 27, 3 September 1999. Editors: Dr. David J. Thomas, Biology and Chemistry Division, Lyon College, Batesville, AR 72503-2317, USA. Marsbugs@aol.com or dthomas@lyon.edu Dr. Julian A. Hiscox, School of Animal and Microbial Sciences, University of Reading, Reading, RG6 6AJ, United Kingdom. J.A.Hiscox@reading.ac.uk Marsbugs is published on a weekly to quarterly 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. Article contributions are welcome, and should be submitted to either of the two editors. Contributions should include a short biographical statement about the author(s) along with the author(s)' correspondence address. Subscribers are advised to make appropriate inquiries before joining societies, ordering goods etc. Back issues and Adobe Acrobat PDF files suitable for printing may be obtained from the official Marsbugs web page at http://www.lyon.edu/webdata/users/dthomas/marsbugs/marsbugs.html . The purpose of this newsletter is to provide a channel of information for scientists, educators and other persons interested in exobiology and related fields. This newsletter is not intended to replace peer-reviewed journals, but to supplement them. We, the editors, envision Marsbugs as a medium in which people can informally present ideas for investigation, questions about exobiology, and announcements of upcoming events. Astrobiology is still a relatively young field, and new ideas may come out of the most unexpected places. Subjects may include, but are not limited to: exobiology and astrobiology (life on other planets), the search for extraterrestrial intelligence (SETI), ecopoeisis and terraformation, Earth from space, planetary biology, primordial evolution, space physiology, biological life support systems, and human habitation of space and other planets. ---------------------------------------------------------------- CONTENTS 1) GALILEO TAKES A CLOSER LOOK AT IO From NASA Space Science News 2) 20 YEARS OF PIONEERING By Larry Klaes 3) EVIDENCE OF EARLIEST ECOSYSTEMS RETRIEVED FROM WEST AUSTRALIAN OUTBACK Department of Minerals and Energy release 4) THIS WEEK ON GALILEO JPL release 5) MARS GLOBAL SURVEYOR STATUS REPORT JPL release 6) MARS POLAR LANDER MISSION STATUS JPL release 7) MARS SURVEYOR 98 MISSION STATUS JPL release ---------------------------------------------------------------- GALILEO TAKES A CLOSER LOOK AT IO From NASA Space Science News 27 August 1999 New pictures of Jupiter's exotic moon were captured on July 3, 1999, as Galileo passed within 81,000 miles of Io. Jupiter's exotic Io is often likened to a pepperoni pizza. Ruddy volcanic plumes that evoke images of sliced Italian sausage among imaginative scientists pockmark its mozzarella- colored surface. The strange appearance of Io's surface is constantly changing as it is formed and reformed by lava flows of molten silicate rock. What drives this volcanic powerhouse? The most likely energy source is changing gravitational tides caused by nearby Jupiter. On July 3, 1999 Galileo flew closer to Io than it has since entering orbit around Jupiter in 1995. During the encounter the spacecraft captured images with a resolution of only 1.3 km per picture element, giving scientists a detailed view of Io's surface. The color image above [in PDF version] was created by combining data from near-infrared, green and violet filters in the spacecraft's camera to approximate what the human eye would see when looking at Io. Comparison of this image to previous Galileo images reveals many changes due to the ongoing volcanic activity. A higher contrast, false color version (below [in PDF version]) shows many small-scale volcanic features which were not recognized previously. Beginning in October 1999, after a series of four orbit-changing encounters with Callisto spanning May to September 1999, Galileo is scheduled to make two daring close approaches to Io, possibly flying through a volcanic plume. The upcoming encounters are expected to yield images of unprecedented clarity and detail. The radiation belts of Jupiter are very intense at Io's distance from the huge planet, and this can disrupt spacecraft functioning. To insure that Galileo will be able to perform science observations from this unique vantage point, the Galileo flight team is preparing contingency plans to protect against radiation-related problems in the coming months. Galileo has been orbiting Jupiter and its moons since December 1995. Its primary mission ended in December 1997, but the spacecraft is currently in the midst of a two-year extended mission. More information about the Galileo mission is available at http://www.jpl.nasa.gov/galileo/ JPL manages Galileo for NASA' s Office of Space Science, Washington, D.C. JPL is a division of the California Institute of Technology, Pasadena, CA. [For more information on this story see http://science.nasa.gov/newhome/headlines/ast27aug99_1.htm] ---------------------------------------------------------------- 20 YEARS OF PIONEERING By Larry Klaes 1 September 1999 On this date twenty years ago, September 1, 1979, the robot probe Pioneer 11 made the first flyby of the planet Saturn, thanks to an impressive gravity boost from its encounter with Jupiter in late 1974. Though its images would not match in quality with the ones taken by Voyager 1 and 2 in the next two years, Pioneer 11 was a true pathfinder for those more sophisticated explorers and all other space vessels to follow. To quote from the main Pioneer web site: [http://spaceprojects.arc.nasa.gov/Space_Projects/pioneer/PN10&1 1.html] Pioneer 11 flew within 13,000 miles of Saturn and took the first close-up pictures of the planet. Instruments located two previously undiscovered small moons and an additional ring, charted Saturn's magnetosphere and magnetic field, and found its planet-size moon, Titan, to be too cold for life. Hurtling underneath the ring plane, Pioneer 11 sent back amazing pictures of Saturn's rings. The rings, which normally seem bright when observed from Earth, appeared dark in the Pioneer pictures, and the dark gaps in the rings seen from Earth appeared as bright rings. To add to this, in order to show just how exciting and dangerous the Pioneer 11 Saturn mission was, the probe came within a celestial hairsbreadth of one of those previously unknown moons. Mission planners also considered sending Pioneer 11 through the Cassini Division in Saturn's rings, as they thought it was an actual empty area in the ring field. Thankfully they decided not to do this to Pioneer 11, as the Cassini Division is full of material like the rest of the rings, only darker. The last communication from Pioneer 11 was received in November 1995, shortly before Earth's motion carried it out of view of the spacecraft antenna. The spacecraft is headed toward the constellation of Aquila (The Eagle), Northwest of the constellation of Sagittarius. Pioneer 11 may pass near one of the stars in the constellation in about 4 million years. Like Pioneer 10, it carries the famous Pioneer Plaque with basic information on the human race that built these first interstellar explorers from Earth. For more information on Pioneer 11: http://www.geocities.com/CapeCanaveral/Launchpad/2099/9711.html http://www.jpl.nasa.gov/calendar/pioneer11.html http://sse.jpl.nasa.gov/missions/sat_missns/p11.html http://spacepc.jpl.nasa.gov/msl/QuickLooks/pioneer10QL.html http://nssdc.gsfc.nasa.gov/cgi-bin/database/www-nmc?73-019A http://spaceprojects.arc.nasa.gov/Space_Projects/pioneer/PNhome. html http://www.nasm.edu/ceps/ETP/SATURN/satpioneer.html http://spaceart.com/solar/cap/sat/titanp11.htm http://www.jpl.nasa.gov/saturn/pio_images.html http://ails.arc.nasa.gov/Images/Astrobiology/AC79-9180.html http://ails.arc.nasa.gov/Images/Astrobiology/AC79-9107.3.html http://ails.arc.nasa.gov/Images/Astrobiology/AC74-9006.html http://www.igpp.ucla.edu/ssc/pdsppi/P11.htm http://www.islandnet.com/~catherin/thisdaytable9.htm ---------------------------------------------------------------- EVIDENCE OF EARLIEST ECOSYSTEMS RETRIEVED FROM WEST AUSTRALIAN OUTBACK Department of Minerals and Energy release East Perth, Western Australia 2 September 1999 Fossil evidence of what is believed to be the world's earliest ecosystems has been found and retrieved from the Western Australian outback and was today handed over to the Western Australian Museum for safekeeping. The structures, which look like egg cartons, represent a small area of exceptionally well- preserved fossil stromatolites (structures built by microbes) that existed around 3.46 billion years ago. The stromatolites probably existed in a volcanic environment at a time when the red and dusty Pilbara looked more like the hot- spring environment of the North American Yellowstone National Park. A group of international experts in palaeobiology and associates of the NASA Astrobiology Institute, which joined an excursion arranged by the Department of Minerals and Energy to study the structures, recently scrutinized the fossilized stromatolites. Director of the Department's Geological Survey Division, Dr. David Blight, said the focus stemmed from an article published in last month's Geological Society of America Bulletin claiming that the fossils provide the best evidence so far discovered of early ecosystems on Earth. University of Montreal's Professor Hans Hofmann, Dr. Kath Grey and Dr. Arthur Hickman of Geological Survey the Department's and Dr Ralph Thorpe of the Geological Survey of Canada jointly wrote the scientific paper. Professor Hofmann said that most of the scientists and paleontologists accompanying the excursion agreed that the highly complex shapes of the structures were the result of biogenic activity, but they would carry out further tests to try and establish the nature of the structures beyond all reasonable doubt. "Unfortunately, studying the fossils wasn't the only motivating factor behind the expedition," co-author Dr. Grey said. Dr. Grey said it was necessary to remove the slab containing the fossils from their bush setting because the ancient stromatolites would surely have become one of the "hottest" items on the international fossil black market. "As these stromatolites were located in a remote area they could not be kept under surveillance and would be easy pickings for an unscrupulous fossil dealer," she said. "Once the article was published we knew that people would be able to narrow down the location of the fossils so we decided the best option was to carefully remove the stromatolites to guarantee their preservation." Dr. Grey pointed out that the theft this decade of 360 million- year old fossil fish remains and fossilized dinosaur footprints near Broome highlighted the need to protect the State's fossils. She also said that the intrinsic value of the fossils was demonstrated by the interest that NASA was showing in studying ancient stromatolites. "Stromatolites are of great interest to the new field of exobiology and are being used by NASA as a model for its search for fossilized life on Mars," Dr Grey said. "Studying early forms of life on Earth could provide the clues needed for the next Mars Lander mission, which sets out in 2003, to find evidence that life once existed on the Red Planet." A former Director of the Department's Geological Survey Division, Alec Trendall, initially discovered the fossil locality. He visited the area in 1984 with Doctors Hickman and Thorpe searching for rocks suitable for isotopic dating. However, it was not until 1997, when the site was investigated in more detail by Professor Hofmann (who was financially supported by the Natural Sciences and Engineering Research Council of Canada) and Dr Grey, that the patch of well-preserved fossils was discovered beneath an overlying rock. Dr. David Blight handed over the fossils to the Western Australian Museum and are now on display at the Museum's Discovery Centre. A web site based on the story of the stromatolites and print quality photographs of their removal can be viewed at www.dme.wa.gov.au/ancientfossils Background of the fossil recovery mission The new stromatolite locality was originally discovered in 1984 in Western Australia's Pilbara, by Dr. Alec Trendall, former Director of the Geological Survey Division (GSD) of the Department of Minerals and Energy in Western Australia. Dr. Kath Grey visited the outcrop later that year, but unable to find the exact site, was not convinced that the structures she saw were fossils and consequently, interest in the outcrop declined. The stromatolite site was visited again by Doctors Trendall and Hickman, together with Dr Ralph Thorpe from the Geological Survey of Canada, in 1990, when photographs were taken of one meter high conical stromatolites embedded in the rock surfaces. Dr. Thorpe later showed these photographs to Professor Hans Hofmann of the University of Montreal and a few samples of the conical structures were made into thin sections. The photos and material convinced Professor Hofmann that the structures might be biogenic. Between 1992 and 1995 several papers were published questioning the biogenicity of previously discovered 3.4 billion year old "fossils" from the Pilbara and the whole question of early Archaean stromatolites was thrown into doubt. Professor Hofmann recognized that the Trendall locality, as the area became known, would be significant in resolving the controversy about the biogenicity of early Archaean stromatolites and referred to the conical structures in a draft publication reviewing the oldest known fossils. This led to extended discussions between Professor Hofmann and Dr. Grey, until a new GSD mapping program in the area finally provided an opportunity in 1997 for both of them to examine the structures in the field, accompanied by Dr. Hickman. Once at the outcrop, it didn't take long for Doctors Hofmann[1] and Grey to agree that the cones (missed by Dr Grey in 1984) were probably biogenic, or for them to discover other complex structures associated with the cones. While working in the area, the three scientists noticed a tiny patch of well-formed cones poking out beneath an overlying rock. Upon removal of the overlying slab, the "egg-carton" surface (a series of small cones preserved three dimensionally) was revealed. Field study was followed by laboratory examination carried out by Professor Hofmann at the University of Montreal, culminating in the publication, in August 1999, of a scientific paper (authored by Hofmann, Grey, Hickman and Thorpe) describing the find. The Trendall locality is of particular significance because of the exceptional preservation and because it exhibits complex shapes consistent with biologic activity at beginning of the fossil record. The structures are of great interest to the new field of exobiology (life on other planets), because NASA's Mars Lander will search for similar structures as part of its mission to the red planet, leaving Earth in 2003, to look for evidence of life on other worlds. After assessing the risk of losing the fossils through theft or erosion if they were left at the locality and mindful that the structures needed to be studied in context, GSD decided to organize an excursion for specialists so they could examine the structures before they were removed. The 1999 visitors (including five associates of NASA's Astrobiology Institute) reacted in much the same way as Doctors Grey, Hofmann and Hickman towards the coniform structures. Most agree that the evidence for biogenicity is very strong based on the shape of the fossils, however, they will now try to find other evidence (such as chemical signatures) that support the claim that the structures were built by living organisms. Because these structures are so significant and because removing them from the locality to protect them was a contentious scientific decision, GSD invited the ABC television science program Quantum to document the removal of the slab to the Western Australian Museum for safekeeping. Footnote [1] Professor Hofmann was funded by the Natural Sciences and Engineering Research Council of Canada. ---------------------------------------------------------------- THIS WEEK ON GALILEO JPL release 30 August - 5 September 1999 Galileo spends this week returning science observations made during its encounter with Jupiter and the Galilean moons in mid- August. The observations are stored on the spacecraft's onboard tape recorder. Five observations are on this week's playback schedule, including measurements made by the Fields and Particles instruments, the Solid-State Imaging camera, and the Near-Infrared Mapping Spectrometer. Data playback is interrupted twice this week. On Monday, the spacecraft performs a standard gyroscope performance test. On Wednesday, the spacecraft performs a test on the Near Infrared Mapping Spectrometer. The Fields and Particles instruments continue the return of their high-resolution recording of Jupiter's magnetosphere (its plasma, dust, and electric and magnetic field environments) and Io torus. The data will contribute to the study of the dynamic processes within the torus in particular and the magnetosphere in general. The Io torus is a region of intense plasma and radiation activity, which is constantly replenished by the volcanic activity on Io. Playback of this observation takes up most of this week's available playback time. Toward the end of the week, Galileo starts with a second pass through the data stored on the tape recorder. This second pass allows the replay of data lost in transmission to Earth, reprocessing of data using different parameters, or return of additional new data. The Solid-State Imaging camera returns one observation that was part of the campaign designed to monitor volcanic plume activity on Io. The next two observations returned by the camera contain images of Amalthea, one of Jupiter's inner moons. The images will provide the best spatial resolution ever obtained of the minor moon and will enhance studies of its shape. The last observation of the week is returned by the Near- Infrared Mapping Spectrometer. The observation contains measurements describing a white oval in Jupiter's atmosphere. White ovals are long-lived storms that tend to form between two adjacent zonal jet streams. For more information on the Galileo spacecraft and its mission to Jupiter, please visit the Galileo home page at http://www.jpl.nasa.gov/galileo. ---------------------------------------------------------------- MARS GLOBAL SURVEYOR STATUS REPORT JPL release 26 August 1999 Launch / Days since Launch = Nov 7, 1996 / 1023 days Start of Mapping / Days since Start of Mapping = April 1, 1999 / 147 days Last Orbit Covered by this Report = 2089 Total Orbits = 3771 Total Mapping Orbits = 2089 Recent events The mm007 sequence has been controlling S/C activities since August 26. This sequence is the first stop the HGA auto- tracking during non-Earth communications periods to further reduce the microphonics noise observed by the Thermal Emission Spectrometer (TES) instrument. The three-stop solar array articulation scheme continues in this sequence and has provided an improvement in TES data quality. Development of the special two-part Magnetometer (MAG) calibration sequence is complete and ready to be loaded for execution on the spacecraft August 31 and September 2. This test is comprised of a series of solar array motions on the night side of the orbit that will be used to more fully characterize the magnetic signature of the spacecraft. Hga anomaly The HGA gimbal is currently operational with full redundancy on side-A. The fault protection threshold for HGA stuck gimbal is at 25 seconds (50 counts). Spacecraft health All subsystems continue to report nominal status. Uplinks There have been 11 uplinks to the spacecraft during the last week, including the mm007 sequence, thruster accumulator reset, and instrument command loads. Total command files radiated to the spacecraft since launch is 3869. Upcoming events 1) MAG calibration on Aug 30 and Sept 2. ---------------------------------------------------------------- MARS POLAR LANDER MISSION STATUS JPL release 1 September 1999 NASA's Mars Polar Lander spacecraft fired its maneuvering engines for 30 seconds this morning to fine-tune its flight path for arrival at the martian south pole on December 3. The burn began at 10:07 a.m. Pacific Daylight Time and increased the speed of the spacecraft by 2.3 meters per second (about 5 miles per hour) so that the Lander will arrive at Mars one hour earlier than previously planned. "It is like we are flying from New York to California and with today's maneuver we decided to land in Los Angeles instead of San Diego," said Dr. Sam Thurman, flight manager for the Mars Polar Lander at NASA's Jet Propulsion Laboratory. "During the next few months leading up to landing, we'll conduct additional maneuvers that will further adjust the flight path, similar to deciding which specific runway at LAX we want to land on." The landing site, announced last week, is located at 76 degrees south latitude and 195 degrees west longitude, near the northern edge of the layered terrain in the vicinity of the Martian south pole. The Lander is now 36.5 million kilometers (22.7 million miles) from Mars, traveling at a speed of 3.7 kilometers per second (about 8,300 miles per hour) relative to the planet. Mars Polar Lander is managed for NASA's Office of Space Science by JPL. JPL is a division of the California Institute of Technology, Pasadena, CA. ---------------------------------------------------------------- MARS SURVEYOR 98 MISSION STATUS JPL release September 1, 1999 Mars Climate Orbiter (MCO) Mars Climate Orbiter continued standard cruise operations during the past week. The flight team conducted the Mars Orbit Insertion (MOI) and Aerobraking Critical Events Reviews on Monday and Tuesday of this week (August 30-31), scrutinizing its plans, procedures, and testing needed for these activities. Next week the team will conduct the final science instrument checkouts prior to Mars arrival, then begin its preparations for the fourth and final course correction, TCM-4. Mars Climate Orbiter is 22 days from MOI. Mars Polar Lander (MPL) This morning the MPL spacecraft executed its Site Adjustment Maneuver successfully, retargeting the landing site to an area centered at 76 deg S Latitude, 195 deg W Longitude in the south polar region. NASA approved this target site on August 24th. The spacecraft conducted a 30-second burn using its four 5-pound thrust maneuvering engines, achieving a 2.3 meter/second velocity adjustment. Spacecraft performance was nominal in all respects. With this maneuver the predicted time of landing moves approximately 1 hr earlier, to 12:00:26 (PST) on December 3, 1999. For more information on the Mars Surveyor 98 mission, please visit our web site at http://mars.jpl.nasa.gov/msp98 ---------------------------------------------------------------- End Marsbugs Vol. 6, No. 27