MARSBUGS: The Electronic Astrobiology Newsletter Volume 9, Number 9, 4 March 2002. Editors: Dr. David J. Thomas, Science Division, Lyon College, Batesville, AR 72503-2317, USA. 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 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/marsbugs.html. _____________________________________________________________________ CONTENTS 1) MICROBES MAY SURVIVE 50 MILES DOWN From SpaceDaily 2) UA RESEARCHER SAYS CATACLYSM THAT RESURFACED THE EARTH AND THE INNER SOLAR SYSTEM 3.9 BILLION YEARS AGO WAS CAUSED BY ASTEROIDS, NOT COMETS By Julieta Gonzalez 3) THE RACE TO FIND LIFE By Seth Shostak 4) TRACTORS, SATELLITES, AND PICKUP TRUCKS By Steve Price and Tony Phillips 5) UA INSTRUMENT ABOARD MARS ODYSSEY DETECTS HYDROGEN AT MARS' SOUTH POLE University of Arizona release 6) ROCK-EATING MICROBES TARGETED FOR STUDY IN DEEP OCEAN OFF PERU Texas A&M University release 7) NEW ADDITIONS TO THE ASTROBIOLOGY INDEX By David J. Thomas 8) NASA'S MARS ODYSSEY SPACECRAFT UNVEILS EARLY SCIENCE RESULTS NASA/JPL release 9) STARDUST STATUS REPORT NASA/JPL release _____________________________________________________________________ MICROBES MAY SURVIVE 50 MILES DOWN From SpaceDaily 26 February 2002 Until now, scientists thought that only specially adapted organisms they call extremophiles could exist in seemingly intolerable environments such as high-pressure, high-temperature oceanic hydrothermal vents or in the ice sheets of Antarctica. A study published in the February 22, 2002, issue of Science, however, shows that even common bacteria are viable under high-pressure conditions equivalent to about 50 kilometers beneath the Earth's crust or 160 kilometers in a hypothetical sea. This finding may expand the habitable zone for life within the solar system and it opens new doors for looking for life much deeper inside planetary bodies than previously considered. According to Dr. Anurag Sharma the lead author, "It is exciting to observe the microbes under such unusual environments. Their continued biological activity says a lot about their resilience." The scientific team is headed by Sharma and James Scott at the Geophysical Laboratory of the Carnegie Institution of Washington. They adapted the tools of high-pressure physics to microbiology by using diamond anvil cells to subject two bacteria species--E. coli commonly found in the human gut, and the metal-reducing Shewanella oneidensis--to pressures up to 16 thousand times the pressure found at sea level. Get the full story at http://www.spacedaily.com/news/life-02k.html. _____________________________________________________________________ UA RESEARCHER SAYS CATACLYSM THAT RESURFACED THE EARTH AND THE INNER SOLAR SYSTEM 3.9 BILLION YEARS AGO WAS CAUSED BY ASTEROIDS, NOT COMETS By Julieta Gonzalez University of Arizona release 27 February 2002 The bombardment that resurfaced the Earth 3.9 billion years ago was produced by asteroids, not comets, according to David Kring of the University of Arizona Lunar & Planetary Laboratory and Barbara Cohen, formerly at the UA and now with the University of Hawaii. Their findings will appear in the Thursday, February 28 edition of the Journal of Geophysical Research published by the American Geophysical Union. The significance of this conclusion is that the bombardment was so severe that it destroyed older rocks on Earth. Which, Kring says, is the reason why the oldest rocks found are less than 3.9 billion years old. Additionally, they argue, impact-generated hydrothermal systems would have been excellent incubators for pre-biotic chemistry and the early evolution of life, consistent with previous work that shows life originated in hot water systems around or slightly before 3.85 billion years ago. This same bombardment according to Kring and Cohen, affected the entire inner solar system, producing thousands of impact craters on Mercury, Venus, the Moon and Mars. Most of the craters in the southern hemisphere of Mars were produced during this event. On Earth, at least 22,000 impact craters with diameters greater than 20 kilometers were produced, including about 40 impact basins with diameters of about 1,000 kilometers in diameter. Several impact craters of about 5,000 kilometers were created as well-each one exceeding the dimensions of Australia, Europe, Antarctica or South America. The thousands of impacts occurred in a very short period of time, potentially producing a globally-significant environmental change at an average rate of once per 100 years. Also, the event is recorded in the asteroid belt, as witnessed by the meteoritic fragments, which have survived to fall to Earth today. Kring, has been involved in the research and measurements of the Chicxulub impact crater located near Merida, Yucatan, Mexico. He has collaborated on and led various international research teams, which have drilled to unearth evidence of the Cretaceous-Tertiary (K/T) impact that is thought to have led to mass extinctions on Earth, including dinosaur extinction. Earlier this month, Kring returned from a drilling operation at the impact site where crews worked around the clock to recover core samples to determine what the impactor was and details of the catastrophic event that wiped out more than 75 percent of all plant and animal species on Earth. Contacts: David Kring, Associate Professor of Planetary Sciences and Director, NASA/UA Space Imagery Center at the University of Arizona Phone: 520-621-2024 E-mail: kring@LPL.arizona.edu Barbara Cohen, Hawaii Institute of Geophysics & Planetology, University of Hawaii at Manoa Phone: 808-956-3901 E-mail: bcohen@higp.hawaii.edu Additional information on this article is available at http://uanews.opi.arizona.edu/cgi-bin/WebObjects/UANews.woa/wa/MainStoryDetails?ArticleID=5072. _____________________________________________________________________ THE RACE TO FIND LIFE By Seth Shostak From Space.com 28 February 2002 The Olympics may still be fresh in your mind, but there's another competition underway whose consequences will hang over the planet a lot longer than this year's pairs skating. It's the race to find the first unequivocal evidence of life somewhere other than Earth. There are two things that are particularly intriguing about this effort: (1) The contestants are running towards wildly different finish lines, and (2) despite the variety of approaches, it's impossible to "call" the race. Anyone could win. Now of course, there are some folks (quite a few, actually) who figure that this race is over, and reluctant scientists are just being difficult about handing over the loving cup. For example, there's the claim that fossilized microbes have been found in Martian meteorites, not to mention the widespread belief that intelligent aliens are visiting Earth. Most scientists are skeptical of both, not because they're fuddy-duddies incapable of thinking out of the box, but because the evidence presented so far has failed to sway their naturally (and correctly) skeptical natures. Get the full story at http://www.space.com/searchforlife/seti_race_020228.html. _____________________________________________________________________ TRACTORS, SATELLITES, AND PICKUP TRUCKS By Steve Price and Tony Phillips From NASA Science News 28 February 2002 The tools of agriculture are changing as growers experiment with new space-age techniques called "precision farming." Neal Isbell prepares for his workday by loading his trusty pickup truck with the everyday essentials of farming: his cap, jacket, extra boots, a box lunch and his dog. And don't forget the laptop computer and a GPS receiver. "The laptop is now an essential part of our farming operation and I have a hard time keeping the dog from stepping on it," laughs Isbell. Isbell's family has been farming in northern Alabama for six generations--but Isbell isn't running the farm as his forefathers did. He is one of a new generation of growers called "precision farmers." Precision farmers use data from satellites and high-flying aircraft to pinpoint problems with drainage, insects and weeds. They learn where fertilizers are needed--and where they're not needed. They discover pests--and spray only the infested areas. It's a remarkably "green" approach to farming that is both friendly to the environment and profitable to the farmer. "We're seeing some real savings in fertilizer applications," says Isbell, "and our fields are more uniformly productive than ever." Despite the advantages of precision farming, however, growers like Isbell remain uncommon. Many farmers simply don't know the technology exists, while others aren't convinced that it makes economic sense. Hoping to change that, NASA launched a program in 1999 called Ag20/20--an industry-government partnership led by NASA and the United States Department of Agriculture (USDA). Ag20/20 partners include the National Corn Growers Association, the National Cotton Council, the United Soybean Board and the National Association of Wheat Growers. "We're educating farmers about precision farming technology and we're collecting hard evidence that it pays for itself," explains Rodney McKellip, who directs the program from NASA's Stennis Space Center in Mississippi. Ag20/20 has dealt mainly with corn, soybeans, cotton and wheat, "because those are the four biggest agricultural commodities in the United States," says McKellip. This year, though, the program will "branch out" to include orchards in Florida and Washington, and perennials--like cranberries and blueberries--in the Northeast. Precision farmer Neal Isbell is a cotton grower with 4200 acres under his care. Such expansive farms are difficult to canvass simply by walking or driving across the fields; they benefit from the "big picture" a satellite or an aircraft can provide. "We use commercial satellites, like Ikonos and QuickBird," says McKellip, "as well as cameras mounted in aircraft." Sometimes NASA lends one of its own aircraft to the cause, but more often Ag20/20 encourages precision farming teams to use local flying services--for example, Agri-Vision, a company in Columbus, Indiana, that collects digital images for agriculture in the Midwest. The cameras used for precision farming are not ordinary. They can photograph a field as it appears not only at wavelengths of visible light, which the human eye can see, but also at near-infrared and thermal infrared wavelengths. "We find that near-infrared images are often the most useful for diagnosing the condition of a crop," notes McKellip. Charles Hutchinson, of NASA Headquarters' Office of Earth Science, explains. Plants are good reflectors of near-infrared rays from the Sun. When the cells in leaves are healthy and turgid, they scatter near-infrared radiation in all directions. But when leaves begin to wilt--because of stress caused by arid soil, pests or disease--they become less reflective. "Stressed out" crops appear as darker-than- average spots in near-infrared images. "The near-infrared part of the electromagnetic spectrum is more sensitive than visible light [to small changes in crop vitality]," continues McKellip. As a result, near-infrared images can pinpoint trouble spots before they become obvious to the human eye. Once trouble spots are identified, a farmer might send out a human scout to see what's wrong. For example, Neal Isbell recently dispatched scouts across his farm to collect soil samples. "We used GPS receivers to keep track of our positions," says Isbell. The samples revealed a pH imbalance in some areas--easily corrected by adding lime to the soil. Farmers have long known that growing conditions weren't the same at all places on their farms, yet until recently they had little choice but to treat their fields uniformly with "one size fits all" solutions. "These days nearly all new farm equipment has, as options, computerized controllers and GPS-guided navigation," says McKellip. "These devices have the ability to turn a sprayer, for example, on and off as it passes through a certain area of a field. This wasn't the case ten years ago." One of the most important challenges for precision farming is getting data while it's still fresh. Farmers with rapidly growing crops need to know the state of their fields now, not days or weeks ago. Aircraft are still the best in this regard. McKellip explains: "An airplane can take pictures any time the weather is clear, but a satellite only passes over a field at a certain time on certain days. We typically get computer-processed data from airborne systems back to the farmer in as little as 24 hours." Satellite images, which require more time to downlink and process, can take from 2 to 7 days to reach a farmer. Such delays won't be a problem forever, though. "Technology is advancing quickly and more of these commercial satellites are being launched each year," he added. Indeed, perhaps only a decade or so hence, Isbell will climb down from his tractor holding a palm-sized computer in direct contact with Earth orbiting satellites. The screen will reveal a map of crop stresses only minutes old. A few buttons punched and automated systems rush to trouble spots spraying precise amounts of pesticides, fertilizer, and water. Satisfied, he'll glance around his burgeoning field. "But wait," he wonders, suddenly puzzled, "where did my dog go?" Fingers snap. "I must've forgot his GPS collar again!" Perhaps some things will never change... Additional information on this article is available at http://science.nasa.gov/headlines/y2002/28feb_farming.htm?list52260. _____________________________________________________________________ UA INSTRUMENT ABOARD MARS ODYSSEY DETECTS HYDROGEN AT MARS' SOUTH POLE University of Arizona release 1 March 2002 The first images and science results from NASA's Mars Odyssey were unveiled today during a press conference held at the Jet Propulsion Laboratory, Pasadena, CA. Odyssey is carrying the Gamma Ray Spectrometer (GRS), built under the direction of Professor William V. Boynton at the University of Arizona Lunar and Planetary Laboratory. The GRS is a suite of three instruments: the Gamma Subsystem, built by the UA; the Neutron Spectrometer, built by Los Alamos National Laboratory; and the High Energy Neutron Detector, provided by the Russian Aviation and Space Agency, Moscow. NASA's Mars Odyssey spacecraft began its science mapping mission on February 19, 2001. After only 10 days, the GRS instruments have made observations of significant quantities of hydrogen within the surface of Mars. The three instruments within the GRS suite have all shown a substantial region located in the southern polar region is very strongly indurated with hydrogen. The hydrogen content is most likely due to substantial quantities of ice, although the amount of ice cannot be quantified yet. "If this is confirmed, this is fantastic. There is the equivalent of at least several percent water south of 60 degrees latitude", said William Boynton, principal investigator of the GRS instrument suite. For many years scientists have speculated that near-surface water may exist on Mars. The Gamma Ray Spectrometer instruments have made the first direct measurements that confirm there are significant amounts of hydrogen just beneath the surface of Mars. Contacts: William V. Boynton Phone: 520-621-6941 E-mail: wboynton@lpl.arizona.edu Heather Enos Phone: 520-621-8279 E-mail: heather@gamma1.lpl.arizona.edu Additional information on this article is available at http://grs.lpl.arizona.edu/results/presscon1/. An additional article on this subject is available at http://www.spacedaily.com/news/mars-odyseey-02e.html. _____________________________________________________________________ ROCK-EATING MICROBES TARGETED FOR STUDY IN DEEP OCEAN OFF PERU Texas A&M University release 4 February 2002 Way down deep in the ocean off the coast of Peru, in the rocks that form the sea floor, live bacteria that don't need sunlight, don't need carbon dioxide, don't need oxygen. These microbes subsist by eating the very rocks they call home. Researchers from the Ocean Drilling Program (ODP) have embarked aboard the world's largest scientific drillship on a voyage to understand the abundance and diversity of these microbes and the environments in which they live. "The implications of this mission are exciting," said Jack Baldauf, deputy director of ODP at Texas A&M University, science operator for the program. "Earlier voyages have found specimens of these bacteria at depths of up to 800 meters below the sea floor, and we estimate that they may number between 10 and 30 percent of the Earth's biota. That means that the biosphere is larger than previously thought--it doesn't just stop at the sea floor." Other expeditions have obtained samples of these bacteria, but little is known as yet about their real numbers, their diversity, or their role in the biogeochemistry of the oceans. "It's like walking into a tropical rainforest for the first time and beginning to identify and count the birds," said Tom Davies, manager of ODP science operations at Texas A&M. "This type of microbiology is a new science field for ODP. Such research raises questions about the presence of life in extreme environments on this planet and possibly other planets." The drillship JOIDES Resolution is scheduled to depart for ODP Leg 201 February 1 from San Diego, CA to core sites in the eastern equatorial and southeast Pacific. Cores containing microbes will be sampled from previously drilled sites, chosen to represent different subsurface environments, such as methane-rich and normal oceanic environments. Jay Miller is the ODP project manager and Texas A&M staff scientist for leg 201. Co-chief scientists are Steven D'Hondt of the University of Rhode Island and Bo Jorgensen of the Max Planck Institute for Marine Microbiology in Germany. The Joint Oceanographic Institutions, Inc. (JOI) manages ODP with advice from Joint Oceanographic Institutes for Deep Earth Sampling (JOIDES). JOI consists of a consortium of major US institutions with marine science programs. The National Science Foundation (NSF), a U.S. government agency, supplies 65 percent of ODP's $46 million annual budget, while 21 international partners contribute the remaining 35 percent of the required funding. Texas A&M is one of two principal ODP contractors. It runs the research ship and hosts one of four repositories for deep-sea ocean core specimens. The ODP's JOIDES Resolution mounts six expeditions a year, each lasting about two months and targeting sites around the globe, chosen with specific scientific goals in mind. The ship houses 13,000 square feet of laboratory space, including 13 different labs for studies ranging from microbiology to geophysics. Typically an international team of 28 scientists participates in each voyage. Lamont Doherty Earth Observatory (LDEO) is the other principal ODP contractor. It is responsible for downhole logging operations and management of the site survey data base. "ODP is uniquely positioned to sample one of the least known and potentially strangest ecosystems on Earth--the microbial biosphere of deep marine sediments and the oceanic crust," Baldauf said. "The growing international interest in the subsurface biosphere is driven by many factors, not the least of which is sheer fascination with the nature of life on the margin of existence." Contacts: Judith White Phone: 979-845-4664 E-mail: jw@univrel.tamu.edu. AggieDaily Office of University Relations Texas A&M University Phone: 979-845-4641 Additional information on this article is available at http://www.tamu.edu/univrel/aggiedaily/news/stories/02/020402-8.html. An additional article on this subject is available at http://www.spacedaily.com/news/life-02l.html. _____________________________________________________________________ NEW ADDITIONS TO THE ASTROBIOLOGY INDEX By David J. Thomas http://www.lyon.edu/webdata/users/dthomas/astrobiology/astrobiology.h tml 4 March 2002 Articles about astrobiology, exobiology and terraformation http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_article s1.html S. Shostak, 2002. The race to find life. Space.com. Articles about the biology of extreme environments (on Earth) http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_article s2.html SpaceDaily, 2002. Microbes may survive 50 miles down. SpaceDaily. SpaceDaily, 2002. Rock-eating microbes survive in deep ocean off Peru. SpaceDaily. _____________________________________________________________________ NASA'S MARS ODYSSEY SPACECRAFT UNVEILS EARLY SCIENCE RESULTS NASA/JPL release 1 March 2002 Initial science data from NASA's Mars Odyssey spacecraft, which began its mapping mission last week, portend some tantalizing findings by the newest Martian visitor, including possible identification of significant amounts of frozen water. "We are delighted with the quality of data we're seeing," said Dr. Steve Saunders, Odyssey project scientist at JPL. "We'll use it to build on what we've learned from Mars Global Surveyor and other missions. Now we may actually see water rather than guessing where it is or was. And with the thermal images we are able to examine surface geology from a new perspective." "These preliminary Odyssey observations are the 'tip of the iceberg' of the science results that are soon to come, so stay tuned," said Dr. Jim Garvin, lead scientist of the Mars Exploration Program at NASA Headquarters, Washington, DC. New images taken by the thermal emission imaging system show the temperature of the surface at a remarkable level of clarity and detail during both the Martian day and night. The images can be seen at http://mars.jpl.nasa.gov/odyssey and http://themis.asu.edu/latest. Odyssey's camera system is studying Mars' surface mineralogy to reveal geologic history. The thermal infrared images are 30 times sharper than previously available images, and the camera's visible- light images will fill a gap in resolution between Viking Orbiter and Mars Global Surveyor pictures. Initial measurements by the gamma ray spectrometer instrument suite show the presence of significant amounts of hydrogen in the south polar region of Mars. The high hydrogen content is most likely due to water ice, though the amount of ice cannot be quantified yet. Further analysis will be conducted to confirm the interpretation. The detection of hydrogen is based both on the intensity of gamma rays emitted by hydrogen, and by the intensity of neutrons that are moderated by hydrogen. The neutron intensity was observed by the high-energy neutron detector and the neutron spectrometer. Additional information is available online at http://grs.lpl.arizona.edu/results/presscon1/. "The preliminary assessment of the gamma-ray spectrometer data indicates the likely presence of hydrogen in the upper few feet of the Martian surface as sampled at spatial scales approximately 400 miles across. Further analysis and another month or so of mapping will permit more quantitative assessment of these observations and allow for a refined interpretation," said Garvin. Measurements made by the Martian radiation environment experiment during Odyssey's cruise phase suggest that the daily dose of radiation experienced by astronauts on their way from Earth to Mars would be more than twice the dose endured by astronauts on the International Space Station. Investigators are in the process of troubleshooting the radiation experiment to determine why the instrument stopped communicating and was turned off in August 2001. The Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, DC. Investigators at Arizona State University in Tempe, the University of Arizona in Tucson, and NASA's Johnson Space Center, Houston, operate the science instruments. Additional science partners are located at the Russian Aviation and Space Agency, which provided the high-energy neutron detector, and at Los Alamos National Laboratories, New Mexico, which provided the neutron spectrometer. Lockheed Martin Astronautics, Denver, is the prime contractor for the 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. Contacts: Guy Webster, JPL Phone: 818-354-6278 Don Savage, NASA Headquarters Phone: 202-358-1727 _____________________________________________________________________ STARDUST STATUS REPORT NASA/JPL release 1 March 2002 There were two Deep Space Network (DSN) passes during the past week and all subsystems are normal. Stardust is currently 2.69 AU (250 million miles, or 402 million kilometers) from the Sun. The currently active sequence contains only short DSN passes in order to ensure that the battery state of charge does not go below 80 percent. The longest DSN pass is 2 hours 15 minutes while the shortest pass is 2 hours 5 minutes. The Principal Investigator participated with the Outreach Manager in a web chat with members of the JPL Ambassadors Program. The Stardust Outreach team submitted two items for consideration by Guinness World Records: JPL's aerogel--the lowest density solid material; and that Stardust has operated successfully the furthest from the Sun on solar power than any other spacecraft. 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 9.