Marsbugs: The Electronic Astrobiology Newsletter Volume 10, Number 45, 18 November 2003 Editor/Publisher: David J. Thomas, Ph.D., Science Division, Lyon College, Batesville, Arkansas 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://www.lyon.edu/projects/marsbugs/. ________________________________________________________________________ CONTENTS 1) ULTRA-LOW OXYGEN COULD HAVE TRIGGERED MASS EXTINCTIONS, SPURRED BIRD BREATHING SYSTEM University of Washington release 2) HYDROGEN SULFIDE, NOT CARBON DIOXIDE, MAY HAVE CAUSED LARGEST MASS EXTINCTION Pennsylvania State University release 3) INTERNATIONAL SPACE STATION CREWS MARK THREE YEARS ABOARD NASA release 4) VOYAGES THROUGH TIME(tm)--A NEW WAY TO TEACH SCIENCE By Edna DeVore 5) DEAN CALLS FOR HUMANS TO MARS Mars Society release 6) MARS-LIKE ATACAMA DESERT COULD EXPLAIN VIKING "NO LIFE" RESULTS NASA/ARC release 03-87AR 7) NOT YOUR TYPICAL "ROCK" TOUR: MARS ROCKS WITH MARSAPALOOZA! NASA/JPL release 8) LOCATION, LOCATION: PUERTO RICO IS LISTENING By Seth Shostak 9) SPACE INVADERS By David H. Grinspoon 10) PREEMIES FROM THE PRECAMBRIAN By Lee J. Siegel 11) PLANETARY SOCIETY JOINS CAMPAIGN TO MAKE HUMAN MARS EXPLORATION NASA'S GOAL Mars Society release 12) KEEPING WATCH FOR INTERSTELLAR COMPUTER VIRUSES By Leonard David 13) WORMS IN THE MIST By Leslie Mullen 14) NOT-YET-TURNED-ON STAR IS FORMING JUPITER-LIKE PLANET By Lori Stiles 15) ESA'S FIRST STEP TOWARDS MARS SAMPLE RETURN ESA release 16) OUR PLACE IN THE COSMOS: BIG HISTORY AND THE STORIES OF SCIENCE By Douglas Vakoch 17) DELTA-LIKE FAN ON MARS SUGGEST ANCIENT RIVERS WERE PERSISTENT NASA/JPL release 2003-151 18) EXTRATERRESTRIAL RESOURCES: "LIVING OFF THE LAND" By Leonard David 19) LIFE'S RECIPE CARD Based on a DOE report 20) ARECIBO DIARIES: ONCE MORE INTO THE BREACH! By Peter Backus 21) DAMAGED JAPANESE SPACECRAFT MIGHT CONTAMINATE MARS IF IT HITS From SpaceDaily 22) SKEPTICISM WITH WONDER: INTERVIEW WITH CAROL OLIVER From Astrobiology Magazine 23) NEW ADDITIONS TO THE ASTROBIOLOGY INDEX By David J. Thomas 24) CASSINI SIGNIFICANT EVENTS NASA/JPL releases 25) MARS GLOBAL SURVEYOR IMAGES NASA/JPL/MSSS release 26) MARS ODYSSEY THEMIS IMAGES NASA/JPL/ASU release 27) MARS ROVER SPIRIT MISSION STATUS NASA/JPL release 2003-144 28) STARDUST STATUS REPORT NASA/JPL release ________________________________________________________________________ ULTRA-LOW OXYGEN COULD HAVE TRIGGERED MASS EXTINCTIONS, SPURRED BIRD BREATHING SYSTEM University of Washington release 31 October 2003 Recent evidence suggests that oxygen levels were suppressed worldwide 175 million to 275 million years ago and fell to precipitously low levels compared with today's atmosphere, low enough to make breathing the air at sea level feel like respiration at high altitude. Now, a University of Washington paleontologist theorizes that low oxygen and repeated short but substantial temperature increases because of greenhouse warming sparked two major mass-extinction events, one of which eradicated 90 percent of all species on Earth. In addition, Peter Ward, a UW professor of biology and Earth and space sciences, believes the conditions spurred the development of an unusual breathing system in some dinosaurs, a group called Saurischian dinosaurs that includes the gigantic brontosaurus. Rather than having a diaphragm to force air in and out of lungs, the Saurischians had lungs attached to a series of thin-walled air sacs that appear to have functioned something like bellows to move air through the body. Ward, working with UW biologist Raymond Huey and UW radiologist Kevin Conley, believes that breathing system, still found in today's birds, made the Saurischian dinosaurs better equipped than mammals to survive the harsh conditions in which oxygen content of air at the Earth's surface was only about half of today's 21 percent. "The literature always said that the reason birds had sacs was so they could breathe when they fly. But I don't know of any brontosaurus that could fly," Ward said. "However, when we considered that birds fly at altitudes where oxygen is significantly lower, we finally put it all together with the fact that the oxygen level at the surface was only 10 percent to 11 percent at the time the dinosaurs evolved." "That's the same as trying to breathe at 14,000 feet. If you've ever been at 14,000 feet, you know it's not easy to breathe," he said. Ward believes low oxygen and greenhouse conditions caused by high levels of methane from intense volcanic activity are likely culprits in mass extinctions that occurred about 250 million years ago, at the boundary between the Permian and Triassic periods, and about 200 million years ago, at the boundary between the Triassic and Jurassic periods. He will make a presentation on the topic Tuesday at the American Geological Society annual meeting in Seattle. The Permian-Triassic extinction is believed to have eradicated 90 percent of all species, including most protomammals, a group of mammal- like reptiles that were the immediate ancestors of true mammals. The Triassic-Jurassic extinction killed more than half the species on Earth, with mammal-like reptiles and true mammals, which evolved during the Triassic Period, hit particularly hard. But dinosaurs, which also evolved between the two extinctions, had little problem with conditions during the Triassic-Jurassic extinction. "The seminal observation is that dinosaurs skated across the second of these mass extinctions, actually increasing in number as they went along, while everything else was dropping around them," Ward said. Scientists know of five mass extinction events in Earth's history, but a cause has been widely agreed upon for only one--the episode at the end of the Cretaceous Period 65 million years ago, when the impact of an asteroid is believed to have brought the demise of the dinosaurs. Such impact also has been suggested as the cause of the Permian-Triassic and Triassic-Jurassic extinctions, but geologists have yet to unearth any indisputable evidence of such an impact, and there is no conclusive evidence of what caused either of the events. Ward said mass spectrometer readings on fossil material, as well as the extinction pattern for fossils in rock outcrops collected from the time of the two extinctions, indicates the events were drawn-out affairs and did not happen suddenly, as they would have with an asteroid impact. In addition, he said it is known which types of creatures, and which breathing systems, best survived the extinction events. The same breathing systems are still present in birds, which are known to fare well at high altitudes, where oxygen levels are substantially lower than at the surface. "The reason the birds developed these systems is that they arose from dinosaurs halfway through the Jurassic Period. They are how the dinosaurs survived," he said. Read the original news release at http://www.washington.edu/newsroom/news/2003archive/10- 03archive/k103103.html. An additional article on this subject is available at http://www.astrobio.net/news/article666.html. ________________________________________________________________________ HYDROGEN SULFIDE, NOT CARBON DIOXIDE, MAY HAVE CAUSED LARGEST MASS EXTINCTION Pennsylvania State University release 3 November 2003 While most scientists agree that a meteor strike killed the dinosaurs, the cause of the largest mass extinction in Earth's history, 251 million years ago, is still unknown, according to geologists. "During the end-Permian extinction 95 percent of all species on Earth became extinct, compared to only 75 percent during the KT when the dinosaurs disappeared," says Lee R. Kump, professor of geosciences. "The end-Permian is puzzling. There is no convincing smoking gun, no compelling evidence of an asteroid impact." Researchers have shown that the deep oceans were anoxic, lacking oxygen, in the late Permian and research shows that the continental shelf areas in the end-Permian were also anoxic. One explanation is that sea level rose so that the anoxic deep water was covering the shelf. Another possibility is that the surface ocean and deep ocean mixed, bringing anoxic waters to the surface. Decomposition of organisms in the deep ocean could have caused an overabundance of carbon dioxide, which is lethal to many oceanic organisms and land-based animals. "However, we find mass extinction on land to be an unlikely consequence of carbon dioxide levels of only seven times the preindustrial level," Kump told attendees today (November 3) at the annual meeting of the Geological Society of America in Seattle. "Plants, in general, love carbon dioxide, so it is difficult to think of carbon dioxide as a good kill mechanism." On the other hand, hydrogen sulfide gas, produced in the oceans through sulfate decomposition by sulfur bacteria, can easily kill both terrestrial and oceanic plants and animals. Humans can smell hydrogen sulfide gas, the smell of rotten cabbage, in the parts per trillion range. In the deeps of the Black Sea today, hydrogen sulfide exists at about 34 parts per million. This is a toxic brew in which any aerobic, oxygen-needing, organism would die. For the Black Sea, the hydrogen sulfide stays in the depths because our rich oxygen atmosphere mixes in the top layer of water and controls the diffusion of hydrogen sulfide upwards. In the end-Permian, as the levels of atmospheric oxygen fell and the levels of hydrogen sulfide and carbon dioxide rose, the upper levels of the oceans could have become rich in hydrogen sulfide catastrophically. This would kill most of the oceanic plants and animals. The hydrogen sulfide dispersing in the atmosphere would kill most terrestrial life. Kump and colleagues, Alexander Pavlov, University of Colorado; Michael Arthur, professor of geosciences, Penn State; Anthony Riccardi, graduate student, Penn State; and Yashuhiro Kato, University of Tokyo, are looking at sediments from the end-Permian found in Japan. "We are looking for biomarkers, indications of photosynthetic sulfur bacteria," says Kump. "These photo autotrophic organisms live in places where there is no oxygen, but still some sunlight. They would have been in their hay day in the end-Permian." Finding biomarkers of green sulfur bacteria would provide evidence for hydrogen sulfide as the cause of the mass extinctions. So, what of the 5 percent of the species on Earth that survived? Kump suggests that the mixing of the deep ocean layers and the upper layer was not uniform and that refugia, places where oxygen still existed, remained, both in the oceans and on land. Additional articles on this subject are available at: http://www.astrobio.net/news/article672.html http://www.spacedaily.com/news/life-03zzn.html ________________________________________________________________________ INTERNATIONAL SPACE STATION CREWS MARK THREE YEARS ABOARD NASA release 5 November 2003 In a period that has exemplified the benefits of international cooperation in space, the International Space Station will complete a third year of permanent human presence aboard on Sunday, November 2. The third year of humans living aboard the station has been marked by the perseverance of the orbiting laboratory and international partnership through the tragedy of the Columbia accident. "Every endeavour that continuously pushes the boundaries of human achievement can have times of both great triumph and great tragedy. The space agencies and nations around the world that are our partners in the Station understand that and they have experienced it," ISS Program Manager Bill Gerstenmaier said. "The perseverance of crewed operations aboard the Station this year has brought the partnership closer together, and it will strengthen the Station through both the improvements in safety that we plan and the lessons we learn together." The eighth resident crew--Commander and NASA ISS Science Officer Mike Foale and Flight Engineer Alexander Kaleri--began a six-month stay aboard the complex October 20. The station remains the largest, most sophisticated and most powerful spacecraft ever built. Until the Space Shuttle fleet returns to flight, the transport of supplies and crews to the Station will be conducted by Russian spacecraft. The majority of power, cooling, volume and research capacity on the station are supplied by U.S. components. The station has a mass of almost 400,000 pounds and an interior volume roughly equal to that of a three-bedroom house. The U.S. Destiny Laboratory now houses seven different research facilities. The International Space Station partnership includes NASA; Rosaviakosmos, the Russian Space Agency; the Canadian Space Agency; the European Space Agency; and the Japanese Aerospace Exploration Agency. At the Kennedy Space Center, FL, 168,000 pounds of additional Station components are being prepared for launch when the Space Shuttle returns to flight. Those components will triple the number of science facilities aboard the orbiting laboratory, increase the total power available for research by over 80 percent and triple the surface area of the Station's solar arrays. Among components at KSC is the second Station laboratory, the Japanese Experiment Module named Kibo. An additional article on this subject is available at http://www.universetoday.com/am/publish/third_year_manned_station.html. ________________________________________________________________________ VOYAGES THROUGH TIME(tm)--A NEW WAY TO TEACH SCIENCE By Edna DeVore From Space.com 6 November 2003 "How does the physical and biological world change over time?" "What causes these changes and how fast do they occur?" "What is the evidence for change in living and physical systems?" These are core questions posed in Voyages Through Time, a new high school science curriculum from the SETI Institute that challenges students to consider the origin and development of the universe, our solar system, life on Earth, and us. A collaborative team of scientists and educators at the SETI Institute, NASA Ames Research Center, the California Academy of Sciences, and San Francisco State University developed Voyages Through Time. The team's vision was to create a scientifically accurate, inquiry-based science curriculum that would be the foundation course for high school science. Thematically, Voyages Through Time focuses on evolution in its broadest meaning. What is changing? What is the rate of change? What are the causes and evidence for change? Students explore these questions through evidence provided in lessons, database investigations, simulations, readings, laboratory experiments, and projects that draw upon multiple disciplines in science. Read the full article at http://www.space.com/searchforlife/seti_devore_time_031106.html. ________________________________________________________________________ DEAN CALLS FOR HUMANS TO MARS Mars Society release 6 November 2003 During an online national town meeting conducted by the Washington Post and Concord Monitor, Democratic presidential hopeful Howard Dean today called for the United States to launch a humans to Mars program. Dean's statement came in response to a question from a citizen from Dallas. The transcript of the exchange reads as follows. Dallas, TX: "If elected President, what are your plans for NASA and the Space Program? Do you think it's time to retire the Shuttle and move on to bigger and better things, such as a human mission to Mars, or returning to the moon?" Howard Dean: "I am a strong supporter of NASA and every government program that furthers scientific research. I don't think we should close the shuttle program but I do believe that we should aggressively begin a program to have manned flights to Mars. This of course assumes that we can change Presidents so we can have a balanced budget again." The Mars Society is a non-partisan organization and does not endorse any candidates. We urge all candidates and political parties to support human Mars exploration. Currently, Mars Society members are engaged in a nationwide mobilization to meet with hundreds of Congressmen in their home districts to convince them that NASA needs a goal for its human spaceflight program, and that goal should be Mars. Mars Society members have also been seeking out the various presidential candidates on the campaign trail and engaging them on this issue. The fact that Dean, who is currently leading the Democratic pack, should come out with such clear support for human Mars exploration shows we are making real progress. Dean supporters should contact their campaign offices and congratulate their candidate for taking his visionary stand in support of an American space program that really goes somewhere--and to the right place at that! Supporters of alternative candidates should contact their campaign offices and urge them not to let Dean be the only candidate in the race with a competent space policy. If they want to beat Dean, they need to take an even stronger stand: humans to Mars within a decade! On to Mars! For further information about the Mars Society, visit our web site at www.marssociety.org. ________________________________________________________________________ MARS-LIKE ATACAMA DESERT COULD EXPLAIN VIKING "NO LIFE" RESULTS NASA/ARC release 03-87AR 7 November 2003 A team of scientists from NASA, the Universidad Nacional Autonoma de Mexico, Louisiana State University and several other research organizations has discovered clues from one of Earth's driest deserts about the limits of life on Earth, and why past missions to Mars may have failed to detect life. The results were published this week in Science magazine in an article entitled "Mars-like Soils in the Atacama Desert, Chile, and the Dry Limit of Microbial Life." NASA's Viking missions to Mars in the 1970s showed the martian soil to be disappointingly lifeless and depleted in organic materials, the chemical precursors necessary for life. Last year, in the driest part of Chile's Atacama Desert, the research team conducted microbe-hunting experiments similar to Viking's, and no evidence of life was found. The scientists called the finding "highly unusual" in an environment exposed to the atmosphere. "In the driest part of the Atacama, we found that, if Viking had landed there instead of on Mars and done exactly the same experiments, we would also have been shut out," said Dr. Chris McKay, the expedition's principal investigator, who is based at NASA Ames Research Center, Moffett Field, CA. "The Atacama appears to be the only place on Earth Viking would have found nothing." During field studies, the team analyzed Atacama's depleted Mars-like soils and found organic materials at such low levels and released at such high temperatures that Viking would not have been able to detect them, said McKay, who noted that the team did discover a non-biological oxidative substance that appears to have reacted with the organics-- results that mimicked Viking's results. "The Atacama is the only place on Earth that I've taken soil samples to grow microorganisms back at the lab and nothing whatsoever grew," said Dr. Fred A. Rainey, a co-author from Louisiana State University, who studies microorganisms in extreme environments. According to the researchers, the Atacama site they studied could serve as a valuable testbed for developing instruments and experiments that are better tailored to finding microbial life on Mars thanthe current generation. "We think Atacama's lifeless zone is a great resource to develop portable and self-contained instruments that are especially designed for taking and analyzing samples of the martian soil," McKay said. More sophisticated instruments on future sample-return Mars missions are a necessity if scientists are to avoid contaminating future martian samples, McKay noted. "We're still doing the first steps of instrument development for Mars." Recently, researchers have developed a method to extract DNA from soil without humans getting involved in processing the data, which is "a step in the right direction," according to McKay. The reason Chile's Atacama Desert is so dry and virtually sterile, researchers say, is because it is blocked from moisture on both sides by the Andes Mountains and by coastal mountains. At 3,000 feet, the Atacama is 15 million years old and 50 times more arid than California's Death Valley. The scientists studied the driest part of the Atacama, an area called the "double rain shadow." During the past four years, the team's sensor station has recorded only one rainfall, which shed a paltry 1/10 of an inch of moisture. McKay hypothesizes that it rains in the arid core of the Atacama on average of only once every 10 years. The Atacama research was funded by NASA's Astrobiology Science and Technology for Exploring Planets program, by Louisiana State University, the National Science Foundation and by several other organizations. The article was also authored by Dr. Rafael Navarro-Gonzalez, Dr. Paola Molina and Dr .Jose de la Rosa from the Universidad Nacional Autonoma de Mexico, Mexico City, MX; Danielle Bagaley, Becky Hollen and Alanna Small, Louisiana State University, Baton Rouge, LA.; Dr. Richard Quinn, the SETI Institute, Mountain View, CA; Dr. Frank Grunthaner, NASA Jet Propulsion Laboratory, Pasadena, CA; Dr. Luis Caceres, Instituto del Desierto y Departameno de Ingenieria, Quimica; and Dr. Benito Gomez- Silva, Instituto del Desierto y unidad de Bioquimica, Universidad de Antofagasta, Antofagasta, Chile. For images of the field experiments, please go to www.sciencemag.org. Contacts: Kathleen Burton NASA Ames Research Center, Moffett Field, CA Phone: 650-604-1731 or 604-9000 E-mail: kburton@mail.arc.nasa.gov Robert Anderson Louisiana State University, Baton Rouge, LA Phone: 225-578-3871 E-mail: rander8@lsu.edu Licenciada Guadalupe Dias Universidad Nacional Autonoma de Mexico, Mexico City, Mexico Phone: 52-55-5622-1087 Email: lupitadi@servdor.unam.mx Additional articles on this subject are available at: http://www.spacedaily.com/news/mars-life-03j.html http://spaceflightnow.com/news/n0311/08marsnolife/ ________________________________________________________________________ NOT YOUR TYPICAL "ROCK" TOUR: MARS ROCKS WITH MARSAPALOOZA! NASA/JPL release 7 November 2003 What in the world is Marsapalooza? Marsapalooza, part of NASA's Mars 2004 ("M2K4") effort to promote the Mars Exploration Rovers mission and NASA Mars education initiatives, is a tour during which a team of youthful scientists and engineers (the "M-Team") will visit five cities across the country to raise public literacy about the Mars mission, to reach out to students in underserved communities, and to present themselves as role models to inspire the next generation of explorers. The tour is the product of a unique partnership involving NASA, the National Science Foundation, Passport to Knowledge, and several museums, planetariums, and science centers across the country. The kickoff event for Marsapalooza will be held on December 2nd in New York City at the American Museum of Natural History. The tour, the partnership's take on Lollapalooza, a concept introduced by alternative rock group Jane's Addiction's front man Perry Farrell as slang for "something or someone striking or unusual", hopes to capture the spirit of a true rock concert tour. Marsapalooza will come complete with special lighting, a video, and its own musical soundtrack, while communicating the message to young people that science and math are cool. M-Team members Jim Rice, Deborah Bass, Zoe Learner, Kobie Boykins, Adam Steltzner, and Shonte Wright, a diverse group of scientists and engineers, will represent the Mars Exploration Rovers mission team. Marsapalooza will begin in New York City, proceed to the Naval Observatory in Washington on December 3, the Adler Planetarium in Chicago on December 4, the Denver Museum of Nature and Science on December 6, and will wrap up at a special, yet-to-be-announced location in Los Angeles on December 8. The public will have a chance in each city to meet with the M-Team, and K-12 students will have the opportunity to participate in hands-on activities and demonstrations related to the science of the Mars Exploration Rovers mission. The rovers, named Spirit and Opportunity, will arrive at Mars in January to examine rocks there with more tools than the much smaller rover of NASA's 1997 Mars Pathfinder mission. One of the messages the M-Team hopes to convey about the Mars Exploration Rovers mission is how exciting and extremely challenging it is to land and operate a rover on Mars. "Making a machine that works perfectly is always a goal, and [to see it] working on Mars is that extra little tidbit that puts it over the top. It's the icing on the cake," commented Kobie Boykins, a mechanical engineer at NASA's Jet Propulsion Laboratory and youthful member of the M-Team. Marsapalooza gives scientists and engineers such as Kobie a chance to show the world that, both literally--the average temperature on Mars is -63 degrees Celsius!--and figuratively, nothing is "cooler" than contributing to one of the greatest space exploration missions of all time. The kickoff event will be Web cast live at http://www.nasa.gov/. Stay tuned to the NASA Web site in the weeks to come to find out more about Marsapalooza and NASA's own rock stars: the M-Team! More information is available at http://mars.jpl.nasa.gov/events/marsapalooza.html. ________________________________________________________________________ LOCATION, LOCATION: PUERTO RICO IS LISTENING By Seth Shostak From Astrobiology Magazine 7 November 2003 Puerto Rico Coast--at first glance, Puerto Rico seems a strange place to eye the sky. A tilted block of land guarding the eastern end of the Greater Antilles, this island boasts no soaring mountains on which an optical telescope could perch, nor an unpopulated outback that would suit the signal-sensitive ears of a radio array. What Puerto Rico does have is geology and location. Stretching across the islands northern edge from the suburbs of San Juan to the western town of Aguadilla is a bumpy, limestone terrain known as karst. Pockmarked from thousands of millennia of rain, the karst is a jumble of haystack hills and broad sinkholes. One of the latter, about 8 miles south of the coastal city of Arecibo, is a perfect natural dimple to house the world's biggest single-dish antenna: the Arecibo radio telescope. Cornell University, which built this instrument in the early 1960s, realized that Puerto Rico offers more than accommodating topography. The islands southern latitude (18 degrees north) ensures that Venus and other members of our solar system pass overhead a big plus for a telescope whose 1,000-foot reflector, aimed at the zenith, is far too large to tilt. Twice a year Spring and Fall we come to Arecibo, to profit from its unrivaled sensitivity in our search for signals from other worlds and other beings. This time, our night-time observing shift will be from 5:00 PM to 8:00 AM, somewhat longer than usual. The run lasts 2-1/2 weeks, which is a very healthy allocation on an instrument in constant and widespread demand by astronomers worldwide. Cornell now operates the observatory under a cooperative agreement with the U.S. National Science Foundation, and Arecibo is frequently busy with studies of pulsars, galaxies, and (as Madison Avenue would gush) a whole lot more. Project Phoenix has been using Arecibo since 1998, and in that time hundreds of nearby star systems have been examined for microwave signals. Unlike other SETI experiments, Phoenix can drill down on its targets to maximize the chances of picking up truly faint emissions. If an extraterrestrial broadcast breathes as much as 0.00000000000000000001 watts onto Arecibo's 18-acre reflector, we could detect it. That's a billion times fainter than kisses blown across a stadium. I was packed and prepped for April in Arecibo, but my connecting flight to the island is hung up in Dallas. An ornery fuel valve necessitates an extra stop, and many of the passengers are peeved. I try to remain philosophical. After all, in November, 1493, when Columbus first stumbled upon the island, it had taken him 40 days to bridge the Atlantic from Cadiz to the Caribbean, a distance roughly comparable to the mileage from California. Despite the delays, my trip is still a hundred times faster than his. Watching the iridescent towns of the Bahamas slide by in the dark waters below, it strikes me how five centuries an eye blink in the history of humanity has changed Puerto Rico from an island awaiting discovery to one from which discovery is made. The plane bounces onto the tarmac in San Juan, and the windows immediately fog up from the humidity. Once outside, I find the evening air a pleasant 77°F. Soon, I'm stuffed into a rental car with fellow astronomer Mike Davis, his wife Jean, a small dog, and an impressive collection of luggage. We snake our way out of the airport, and ease on to the freeway to the west. It takes just over an hour to reach the small, labyrinthine roads that lead to the observatory. Somewhat after midnight we pull into the observatory gates, and I collect my cabin key. The coquis, thumb-size frogs with watermelon-size throats are out in force, lacing the humid air with their familiar ko- kee calls. In the near distance, the tracking motors of the telescope grind and groan. I find my way to bed. The morrow will bring work, yes; but also promise. Read the original article at http://www.astrobio.net/news/article662.html. ________________________________________________________________________ SPACE INVADERS By David H. Grinspoon From Astrobiology Magazine 8 November 2003 Sixty-five years ago, on "mischief night," Orson Welles spooked millions of radio listeners with his legendary "War of the Worlds" broadcast [October 30th]. Many who did not hear the "only fiction" disclaimers fled their homes to avoid imminent gas attack by marauding Martians who had landed in Grovers Mill, NJ, creating traffic jams and sending dozens to the hospital for shock and hysteria. Could this happen today? In an age of multiple media, radio has lost some of its punch, but a well-executed Internet hoax of an alien invasion might set some hearts racing. Public fascination with the possibility of extraterrestrial life shows no sign of abating, and the scientific search for it has gained respectability in recent years with the formation and growth of NASA's Astrobiology Institute. The threat of invasion by intelligent, high-tech aliens is not one to lose sleep over. Why would aliens even want our Earth? One of the few things we have learned about planets is that they are complex individuals no two will be exactly alike. Aliens will surely be better adapted to their own planets, and it is highly unlikely that they will be able to breathe our air or infect us, let alone eat us at least not without some expensive and messy food processing. As entertaining as "War of the Worlds" was for those who did not need treatment for shock or hysteria afterwards, Welles' scenario is not a likely one. But there is another threat that deserves immediate attention: the remote but scary possibility of accidental microbial contamination from space. In H. G. Wells' original "War of the Worlds" (1897), the superior Martian invaders were defeated in the end by "the humblest thing that God in His wisdom put upon this Earth" by microbes, who caused the defenseless Martians to catch colds and die. You may not know it, but NASA is guarding you against this danger through the "Office of Planetary Protection," which is charged with preventing the inadvertent spreading of life between worlds during space exploration. Our efforts to prevent "back contamination" the accidental return to Earth of dangerous alien microbes from other worlds are the subject of a new NASA report that details how we might test for living organisms in returned samples. NASA intends to return a sample from Mars within the next decade or two. NASA is also making concerted efforts to prevent "forward contamination," in which we would be the evil alien invaders who seed other planets with Earth bugs. NASA crashed the Galileo spacecraft into Jupiter last month in an effort to avoid the remote possibility that the spacecraft would one day smash into Europa and cause an unforgivable planetary pandemic on that watery moon. Three new spacecraft are headed for landings on Mars in the next couple of months, and their missions are all focused on the search for current life, past life and conditions conducive to life. These craft have all been carefully sterilized so that we will not return to Mars one day to find Earthly life forms that we accidentally deposited in an earlier voyage. Although issues of interplanetary contamination may seem fantastic, they force us to confront the limits of our knowledge about life and where it might thrive. Some prominent scientists have criticized "planetary protection" as based on dubious science, but there is humility and wisdom in this approach. It is true that if our current concepts of biology are correct, then there is virtually no possibility that an alien organism, not adapted for this world, could dangerously out- compete the locals who are marvelously fit to survive here. "Planetary protection" contains an implicit acknowledgement that scientific knowledge is never final or complete. We have been wrong before in the history of space exploration, and we should not wager our planet's safety on the assumption that we need not worry about extraterrestrial life accidentally brought back to Earth. All of our ideas about life elsewhere are based on extrapolation from one example Earth life and science is not at its best when basing sweeping conclusions on a sample size of one. Although common sense strongly suggests that the threats are minimal, we are wise not to ignore them. Let's face it, human intelligence puts us at greater risk than the possibility that malevolent aliens may someday wander through our corner of the galaxy. The fact that we take planetary protection seriously, though, hints that we may have the tools to tame the beast within and use our brains wisely in the service of life. Through the "safe exploring" embodied in planetary protection, we take the best in our nature with us as we take our first steps beyond the Earth. There is no way to stay 100 percent safe from scary monsters that might lurk in the cosmos, but it would be paranoid and self-defeating to avoid exploration out of vague fears of the unknown. With planetary protection, we strive to insure that, through the marvelous tricks of space exploration, we do not give or receive any unwelcome and dangerous planetary treats. What's next? Some might argue that the precautions of containment or sterilization are not necessary, since samples from other celestial bodies have been falling on Earth since its origin. Comets and asteroids are believed to have impacted the Earth frequently in its earliest years, seeding the young planet with water and organic chemicals. The only samples that have been returned to Earth so far have come from the moon. Astronauts on the Apollo missions returned 379 kilograms (835 pounds) of rock and soil from the Moon, and three Russian spacecraft (Luna 16, 20 and 24) also returned moon samples. The samples were kept in sealed containers until they arrived at their respective laboratories for study. According to says John Rummel, NASA's Planetary Protection Officer, there are no set plans to bring a Mars sample back to Earth. However, some proposals discuss having both the European Space Agency and NASA launch martian sample return missions by 2011, with samples returning to Earth by 2016. Sample return missions currently in progress include spacecraft designed to sample a comet, an asteroid, and the solar wind. Although life is not likely to be found in these places, the precursor chemicals that make life possible may be present. NASA's Stardust mission, launched in 1999, will reach comet Wild 2 in January 2004. Stardust will return to Earth with both cometary and interstellar dust particle samples in January 2006. NASA's Genesis mission was designed to collect solar wind samples. The spacecraft was launched in August of 2001 and is now collecting particles coming off the sun. The samples will be returned to Earth in September 2004. Japan's MUSES-C spacecraft, launched May 2003, is headed for asteroid 1998 SF36. After its arrival in June 2005, the spacecraft will gather up to one gram of material from a variety of sites on the asteroid. The samples are expected to arrive back on Earth by June 2007. Read the original article at http://www.astrobio.net/news/article663.html. ________________________________________________________________________ PREEMIES FROM THE PRECAMBRIAN By Lee J. Siegel From Astrobiology Magazine 10 November 2003 "In the eyes of most naturalists, the structure of the embryo is even more important for classification than the adult." --Charles Darwin, On the Origin of Species In his 1859 classic, On the Origin of Species, Charles Darwin noted that even when adult animals of different species look distinctly different, the similar appearance of their embryos could reveal how they are related, and how they descended from a common ancestor. Now, almost a century and a half later, scientists are using a new technique called microCT--a spin-off of the medical CAT scan--to study rare fossils of the early-stage embryos of what may be Earth's oldest animals. While the fossils examined so far are no bigger than 32-cell embryos, they suggest the earliest stages of animal development haven't changed much in 600 million years. Once more mature embryo fossils are found, researchers hope microCT will shed light on evolution of Earth's earliest animals and, ultimately, on how the development of embryos evolved over time. "By looking at these fossils, we're trying to identify who were the first animals swimming around in the ocean or sitting on the seafloor, what environments were they living in--shallow marine settings or the deep sea--and what did they eat," says Whitey Hagadorn, an assistant professor of geology at Amherst College in Massachusetts. Hagadorn used microCT to study fossils collected during the past five years from the Doushantuo Formation in southwest China. The rock contained what appear to be fossils of ancient algae and early-stage embryos of unknown animals. "They are possibly the oldest fossils of animals on Earth," says paleontologist David Bottjer of the University of Southern California. Recent dating, based on the decay of one lead isotope to another, puts the fossils' age at 599 million years, give or take 4.2 million years, which would make them the oldest known animal fossils, Bottjer says. "If you don't look at them real close, they look like little round balls," Hagadorn says. The fossil embryos range from 100 to 500 microns in diameter (a hair is about 50 to 75 microns wide). Algae found in the same formation are roughly one-tenth as wide. Hagadorn says he and his collaborator, Shuhai Xiao of Virginia Tech, have identified nine different forms or "morphotypes" among the dozens of animal embryo fossils they examined. These included embryos comprised of 1, 2, 4, 8, 16 and 32 cells, plus others with envelopes or coatings that were thin or thick. Hagadorn and Xiao don't know if the nine types of embryos represent one or more species of early animal. "There could be many taxa here that all develop in the same way, and we might not recognize it," Hagadorn says. "We don't know exactly what those embryos are," says Bottjer. "It's hard to know are they sponges or cnidarians [animals such as sea anemones, jellyfish and corals]." Hagadorn says fossilized embryos are "incredibly rare," and were preserved because their organic matter was replaced by calcium phosphate, which has tiny crystals that are not big enough to destroy fine structures such as individual cells. The discovery of ancient fossilized embryos "demonstrates that remarkably unpreservable material can be preserved," says Bruce Runnegar, a professor of paleontology at the University of California, Los Angeles, and director of the NASA Astrobiology Institute. "The last thing you'd expect to find in the fossil record 500 million years in age or more are embryos." Runnegar and Bottjer both note that with a maximum of 32 cells, there is only so much information to be obtained from the embryos Hagadorn examined. "It's a little difficult to do the compete embryology using what's been discovered," Runnegar says. "Of course it's really exciting there are any [fossil] embryos and that we know anything about them at all." Yet, "what is really remarkable is that these fossilized embryos seem to be very similar to modern invertebrate embryos," says Bottjer, a professor of earth and biological sciences who once was Hagadorn's adviser at USC. "They certainly tell us that how you start to build an animal hasn't changed a whole hell of a lot since animals evolved," even if adult forms of animals diverged considerably. Bottjer suspects that "even though they are the oldest fossils, there was probably a lot of evolution that went on beforehand, because the embryos already have a lot of features of modern embryos." In the future, researchers want to use microCT on more mature fossil embryos to study how embryonic development changed over time. "Evolutionary and developmental biology have begun to make predictions about how and when ancient animals diverged from one another," says Hagadorn. "One of the ways they are thought to have diverged is through different developmental pathways. So what does a many-celled embryo do differently that causes it to change into a sponge versus a coral? We have potential way to test that by looking at different stages represented in ancient embryos." "Whitey's [microCT] method is going to be able to give us a detailed 3-D description of these embryos and any others we find," Bottjer says. "It's going to be very useful," Runnegar says. "We can see the three- dimensional geometry [of fossilized embryos] fairly easily in a nondestructive way." He says that for more than a century, paleontologists have sectioned fossils and drawn a series of pictures of the cross-sections to construct three-dimensional images. More recently, paleontologists have used room-sized medical CT (computerized tomography) scan equipment to X-ray fossils such as dinosaur skulls, making three-dimensional images from a series of "slices" to get an idea of the internal structure, or to locate the fossil within rock. MicrofocusCT or microCT, uses the same technology as medical CAT scans but in a version that first was miniaturized to look for microscopic defects in manufactured products such as aircraft components. Hagadorn, working with geologist Shuhai Xiao of Virginia Tech in Blacksburg, Virginia, pioneered the use of desktop microCT equipment to examine the internal structure of ancient embryo fossils. Hagadorn started using microCT while doing postdoctoral research at NASA's Jet Propulsion Laboratory (JPL), which was studying the technique for possible use on future Mars rover vehicles. JPL's tabletop device measures roughly 2.5 feet wide by 5 feet long and is attached to a computer that combines X-ray cross sections into three-dimensional images. Before the advent of microCT, the embryo fossils had been examined with other methods. Scanning electron microscopes (SEM) showed individual cells within the embryos, and could distinguish them from algal cells. Cells within an animal embryo deformed each other more than the stiffer plant cells in algae. Conventional and petrographic microscopes were used to examine thin sections shaved off embryo fossils. They revealed internal structures inside the embryos, including cell membranes and dark spots that some scientists have suggested might be cell organelles, Hagadorn says. He says microCT revealed even more about the embryos and the cells within them, including the way they are packed together to form hexagonal, pentagonal and other multifaceted faces typical of modern animal embryo cells. In the four-celled embryos, "we saw paired ovoidal structures with a nucleus-like shape - like seeing seeds within the grapes," says Hagadorn. "There are two of them in each cell. We really don't know what they are," although he wonders if the twin ovoids might be cell nuclei fossilized in the process of dividing. What's next? In addition to conducting more microCT studies of the primitive embryos, Hagadorn wants to confirm or rule out whether their cells' internal structures are cell nuclei. "We look forward to scanning a lot more samples and investigating these embryos in detail," he says. "Maybe two years down the line someone will find another deposit [with fossils] that we can use this technique to look at." Hagadorn wants to search for embryo fossils in slightly younger rock formations in China and Russia, and see how they changed from their Doushantuo ancestors. Bottjer says paleontologists have scratched only the surface in extracting animal embryos and other fossils from the Doushanto. "There could be all sorts of interesting things to be discovered," he says. Read the original article at http://www.astrobio.net/news/article667.html. ________________________________________________________________________ PLANETARY SOCIETY JOINS CAMPAIGN TO MAKE HUMAN MARS EXPLORATION NASA'S GOAL Mars Society release 10 November 2003 Acting in tandem with the Mars Society's current political mobilization, The Planetary Society has imitated a campaign to urge the Bush administration to make human Mars exploration NASA's driving goal. The Planetary Society's move could not have come at a more opportune moment. With the failure of the aimless destination-free approach to NASA operation's now evident, the Bush administration is conducting a review of U.S. space policy, and is preparing to set a goal for NASA. The key issue is what that goal will be; the Moon, or a Mars program that will give us access to the Moon and the near Earth asteroids as well. It is essential that the bolder latter goal be embraced, or NASA will enter a lunar cul-de-sac that will lead nowhere else. To facilitate citizen political action on behalf of the Mars goal, the Planetary Society has set up a weblink at http://www.planetary.org/action/president_letter.html. If you go there, you can fill out a brief form and the system will automatically fax or send by postal mail a letter to President Bush urging a humans to Mars program. You can use the TPS draft letter, which is pretty good, or you can change to text as you desire. The Planetary's Society's suggested draft message reads as follows. Dear President Bush: Your Administration is conducting a review of U.S. space policy. Our nation needs the challenge of grander space exploration, beyond just circling our own planet. To justify the risk and cost of human space flight, we must lift our sights, fuel human dreams and advance human discovery and knowledge. We urge you to direct NASA to devise a plan for human exploration beyond Earth orbit with the ultimate goal of landing humans on Mars sometime in the first decades of this new century. Mars is the most exciting and rewarding destination for exploration in our Solar System, and the one place that can galvanize human interest like no other. Sincerely, Your Name The Mars Society fully supports this imitative. We urge everyone to send a letter to President Bush today urging that NASA adopt humans to Mars as its goal. You can use the convenient Planetary Society system, or just write and mail a letter via U.S. mail. The President's address is President George W. Bush, The White House, 1600 Pennsylvania Ave. NW, Washington, DC 20500. Do it either way, but act today. Humanity's future in space could depend on it. For further information about the Mars Society, visit our web site at www.marssociety.org. ________________________________________________________________________ KEEPING WATCH FOR INTERSTELLAR COMPUTER VIRUSES By Leonard David From Space.com 11 November 2003 Microsoft may have to fork up big bounty bucks trying to unearth future hackers, particularly when they are light years away on distant worlds. Add one more worry to the computerized world of the 21st century. Could a signal from the stars broadcast by an alien intelligence also carry harmful information, in the spirit of a computer virus? Could star folk launch a "disinformation" campaign--one that covers up aspects of their culture? Perhaps they might even mask the "real" intent of dispatching a message to other civilizations scattered throughout the Cosmos. These are concerns that deserve attention explains Richard Carrigan, Jr., a physicist at the Fermi National Accelerator Laboratory in Batavia, Illinois. Those engaged in the Search for Extraterrestrial Intelligence (SETI), he contends, should think about decontaminating potential SETI signals. The so-called "SETI Hacker" hypothesis, Carrigan argues, is an issue of interstellar discourse that should be taken seriously. We should exercise caution when handling SETI downloads, he said. Read the full article at http://www.space.com/scienceastronomy/space_hackers_031111.html. ________________________________________________________________________ WORMS IN THE MIST By Leslie Mullen From Astrobiology Magazine 12 November 2003 To see what sort of wildlife gathers at the shoreline, look for prints pressed into the wet sand. Hermit crab, sandpiper, five-toed Speedo- wearer... Look quickly, for the incoming tide will soon wipe the sands clean. Some animals can leave a more permanent footprint, however. Preserved in Cambrian sandstone are trails made by worm-like creatures wriggling in what was once the wet sand of tidal areas. Such "trace" fossils are fairly common in Cambrian rocks. Most of these trace fossils were made by creatures burrowing down into the sand. The tracks were preserved partly because they were made below the surface, away from the erasing action of water. But some tracks made on the surface also have been preserved, especially if the organism who made them used mucus for locomotion. As it slid along, plowing a ditch in the sand, the mucus coating the body caused the sand grains to clump together. The clumped sand withstood being broken apart by water long enough to be buried by more sand. Last year, Birger Rasmussen, Ian Fletcher, and Neal McNaughton of the University of Western Australia, along with Stefan Bengtson of the Swedish Museum of Natural History, reported finding such surface trace fossils in rocks from Australia's Stirling Range Formation. However, the Stirling rocks pre-dated the Cambrian period by several hundred million years, forming long before multi-celled mobile animals were supposed to have evolved. In the journal Science, the scientists reported that the age of the Stirling rock was somewhere between 1.2 to 2 billion years old. Life 1.2 to 2 billion years ago was mainly composed of microscopic, single-celled bacteria and archaea. Single-celled algae--members of the eukaryotic branch that now includes plants, fungi, and animals--made their first tentative appearance 1.8 billion years ago. According to the fossil record, multi-cellularity took a long time to get going. There are well-preserved fossils of multi-cellular algae dating back 1.2 billion years. The oldest multi-celled animal fossils are less than 600 million years old, dating back to right before the Cambrian explosion. Why did multi-cellular life take so long to get going? The origin of multi-cellular life may be related to the rise of oxygen on Earth, because a larger body composed of multiple cells needs the extra energy that oxidation provides. Based on clues in rocks, the first major boost of oxygen probably occurred between 2.5 and 2 billion years ago. Presumably, multi-cellular life could have appeared soon after the rise in oxygen. Molecular clock dating is not inconsistent with this idea, placing the emergence of multi-cellular life to sometime between 700 million and 1.5 billion years ago. [Molecular clocks are based on the assumption that evolutionary changes in the genetic code are roughly correlated with the passage of time.] The tracks in the Stirling rocks, if they were made by multi-cellular organisms, would provide another line of evidence for the early emergence of multi-cellular life. The Stirling tracks are about two millimeters wide and several centimeters long. Some of the tracks are wider at one end, suggesting that whatever made them stretched out and became slimmer when it moved. Some of the tracks terminate in a U- shape, suggesting a point where the creature may have stopped in its wanderings. According to Bengtson, although the Stirling tracks look like they were made by a worm-like animal, the creature that made the tracks was most likely not a worm, or even the primitive ancestor of a worm. Instead, it may have been an organism that died out long before multi-cellular animals emerged. The rock itself tells us that this creature--whatever it was--lived in a shallow-water tidal environment. Ripple marks and mud cracks indicate the sand was deposited in a shallow sea. The rocks can't yield any biological information, such as DNA, because during burial the rocks became heated and oxidized. Any biological remains have long since been degraded. "DNA, in particular, is a fragile molecule and is not known to have survived for more than some tens of thousands of years," says Bengtson. "The Stirling fossils are about a hundred thousand times older than that." The Stirling rocks also display disc-shaped structures in several of the rock layers. Similar discoidal fossils have cropped up in other ancient rocks, and one interpretation is that they are the holdfasts of sponge- like animals that embedded themselves in the ocean bottom. Sponges branched away very early in the history of animals, and therefore are quite different from what we normally think of as an "animal." They are rooted in place like a plant, and composed of various cells that work to draw in nutrients from the surrounding seawater. The earliest sponge fossils date back to about 600 million years ago. There is no evidence that the disc-shaped structures in the Stirling rocks are the remains of sponges. And although the discoidal fossils appear in the same rock as the trace fossils, Bengtson says the different structures don't have anything to do with each other. Bengtson doesn't think the tracings in the rock could have been made by algae, with grass-like strands that traced loops into the wet sand. The reason, he says, is that such random tracings are inconsistent with the patterns in the Stirling rocks. "The Stirling fossils form a very conspicuous double-stranded structure, where the two strands join in a loop at one end and form a flaring opening at the other," says Bengtson. "Interpreting them as folded single threads likewise meets with difficulties, as there is no reason why these would always be folded at the middle and remain at the same distance from each other." Doug Erwin of the Smithsonian Museum of Natural History thinks looking for biological causes for the Stirling markings is the wrong approach. Instead, he says we must presume the markings are made by non-biological sources, unless proven otherwise. "Extraordinary claims require extraordinary evidence, as the saying goes, and I don't think the Science article rises to that level," says Erwin. "The variety of apparent traces is striking, and many do not appear to be biologic. I guess my concern is that the authors, unintentionally, have selected the most biologic looking objects from a large population." Bengtson counters this concern by saying that the illustrations published with their Science article showed the total variation of markings associated with the traces, without selection for biological- looking objects. But the age of the rocks remains a sticking point with Erwin. Because the rocks are so old, he says, more evidence is needed to prove biology. Just because the tracings look similar to Cambrian tracings is not sufficient evidence for a biologic origin. Erwin suggests that the trace fossils could have been created by such non-biological means as cracks, various sedimentary processes, or torn microbial mats (which are non-biological in the sense that they are accumulations of trapped matter). Bengtson and his colleagues considered these possibilities in their Science paper, but discounted them. The markings were not made by geological processes, they say, because the rocks lack the features you would expect to see from such an origin. The tracings don't resemble swash marks, rill marks, or shrinkage cracks. Bengtson and his colleagues don't believe that microbial mats could have made the tracings, either. They say that torn mats are dominated by irregular, contorted, and twisted structures, which are not found in the Stirling rocks. Interpreting the structures as microbial mats, says Bengtson, "now seems to be the popular excuse to dismiss the Stirling fossils, even though nobody has even tried to explain how these structures could have been formed by disruption of mats." The Stirling fossils are not the only trace fossils under contention. Other wiggly grooves have been found in 1.6-billion-year-old sandstone from central India. The scientists who reported these tracks concluded they were made by a worm-like animal that propelled itself with rhythmic muscle contractions. They also concluded that the animal grazed on decayed microbial mats on the sea floor, because the tracings follow the base of a thin veneer of darker sandstone that may be the remains of a mat. According to Erwin, there is a very long history of such claims of ancient trace fossils. "Most of them simply die off and don't get cited," says Erwin. "I think it is fair to say that they haven't achieved much acceptance within the paleontological community." What's next? The reluctance of the paleontological community to accept the Stirling markings as trace fossils dismays Bengtson, but he seems even more pained when scientists don't even try to suggest plausible alternative hypotheses for the structures. "So far I'm disappointed by the general reception--I had hoped for more challenging and constructive criticism than we have received so far," he says. Still, Bengtson and Birger Rasmussen are continuing to study the Stirling fossils, as well as other trace-like fossils in ancient rocks. "In a field full of potential pitfalls, we need to analyze all new finds with the utmost care," says Bengtson, "An unconditional search for such traces is necessary, if we are ever to get a representative picture of the emergence of multi-cellular life on Earth." Read the original article at http://www.astrobio.net/news/article669.html. ________________________________________________________________________ NOT-YET-TURNED-ON STAR IS FORMING JUPITER-LIKE PLANET By Lori Stiles University of Arizona release 12 November 2003 University of Arizona astronomers have used a new technique called nulling interferometry to probe a dust disk around a young nearby star for the first time. They not only confirmed that the young star does have a protoplanetary disk--the stuff from which solar systems are born- -but discovered a gap in the disk, which is strong evidence of a forming planet. "It's very exciting to find a star that we think should be forming planets, and actually see evidence of that happening," said UA astronomer Philip Hinz. "The bottom line is, we not only confirmed the hypothesis that this young star has a protoplanetary disk, we found evidence that a giant, Jupiter-like protoplanet is forming in this disk," said Wilson Liu, a doctoral student and research assistant on the project. "There's evidence that this star is right on the cusp of becoming a main-sequence star," Liu added. "So basically, we're catching a star that is right at the point of becoming a main-sequence star, and it looks like it's caught in the act of forming planets." Main-sequence stars are those like our sun that burn hydrogen at their cores. Earlier this year, Hinz and Liu realized that observations of HD 100546 at thermal, or mid-infrared, wavelengths showed that the star had a dust disk. Finding faint dust disks is "analogous to finding a lighted flashlight next to Arizona Stadium when the lights are on," Liu said. The nulling technique combines starlight in such a way that it is canceled out, creating a dark background where the star's image normally would be. Because HD 100546 is such a young star, its dust disk is still relatively bright, about as bright as the star itself. The nulling technique is needed to distinguish what light comes from the star, which can be suppressed, and what comes from the extended dust disk, which nulling does not suppress. Hinz and UA astronomers Michael Meyer, Eric Mamajek, and William Hoffmann took the observations in May 2002. They used BLINC, the only working nulling interferometer in the world, along with MIRAC, a state- of-the-art mid-infrared camera, on the 6.5-meter (21-foot) diameter Magellan telescope in Chile to study the roughly 10-million-year-old star in the Southern Hemisphere sky. Typically, dust in disks around stars is uniformly distributed, forming a continuous, flattened, orbiting cloud of material that is hot on the inner edge but cold most of the distance to the frigid outer edge. "The data reduction was complicated enough that we didn't realize until later that there was an inner gap in the disk," Hinz noted. "We realized the disk appeared about the same size at warmer (10 micron) wavelengths and at colder (20 micron) wavelengths. The only way that could be is if there's an inner gap." The most likely explanation for this gap is that it is created by the gravitational field of a giant protoplanet--an object that could be several times more massive than Jupiter. The researchers believe the protoplanet may be orbiting the star at perhaps 10 AU. (An AU, or astronomical unit, is the distance between Earth and the sun. Jupiter is about 5 AU from the sun.) Astronomers from the Netherlands and Belgium had previously used the Infrared Space Observatory to study HD 100546, which is 330 light-years from Earth. They detected comet-like dust around the star and concluded that it might be a protoplanetary disk. But the European space telescope was too small to clearly see dust surrounding the star. Hinz, who developed BLINC, has been using the nulling interferometer with two 6.5-meter telescopes for the past three years for his survey of nearby stars in search of protoplanetary systems. In addition to the Magellan telescope that covers the Southern Hemisphere, Hinz uses the 6.5-meter UA/Smithsonian MMT atop Mount Hopkins, AZ, for the Northern Hemisphere sky. Hinz developed BLINC as a technology demonstration for the Terrestrial Planet Finder mission, which is managed for NASA by the Jet Propulsion Laboratory, Pasadena, CA. NASA, which funds Hinz' survey, supports research on solar-system formation under its Origins program and is developing nulling interferometry for Terrestrial Planet Finder. "Nulling interferometry is very exciting because it is one of only a few technologies that can directly image circumstellar environments," Liu said. Using MIRAC, the camera developed by William Hoffmann and others, was important because it is sensitive to mid-infrared wavelengths, Hinz said. Astronomers will have to look in mid-infrared wavelengths, which correspond to room temperatures, to find planets with liquid water and possible life, he said. Hinz' survey includes HD 100546 and other "Herbig Ae" stars, which are nearby young stars generally more massive than our sun, but are not yet main sequence stars powered by nuclear fusion. Hinz and Liu plan to observe increasingly mature star systems, searching for ever-fainter circumstellar dust disks and planets, as they continue to improve nulling interferometry and adaptive optics technologies. Adaptive optics is a technique that eliminates the effects of Earth's shimmering atmosphere from starlight. Hinz and others at UA Steward Observatory are designing a nulling interferometer for the Large Binocular Telescope, which will view the sky with two 8.4-meter (27-foot) diameter mirrors on Mount Graham, AZ, in 2005. The UA team is reporting the research in Astrophysical Journal Letters and also will present a paper on the research at the American Astronomical Society meeting in Atlanta, GA, in January 2004. Read the original news release at http://uanews.org/cgi- bin/WebObjects/UANews.woa/5/wa/SRStoryDetails?ArticleID=8087&wosid=94M3Y ftkfZ9gN00356xz8w. An additional article on this subject is available at http://www.universetoday.com/am/publish/unstarted_star_seen.html. ________________________________________________________________________ ESA'S FIRST STEP TOWARDS MARS SAMPLE RETURN ESA release 12 November 2003 What is the next best thing to humans landing on Mars and exploring the wonders of the Red Planet? The answer: touching, imaging and analyzing carefully preserved samples of martian rock in a state-of-the-art laboratory on Earth. If all goes according to plan, this is exactly what ESA's long-term Aurora Programme of solar system exploration will achieve a decade from now, when the first samples of Mars material will be sealed in a special capsule and returned to Earth for analysis. The first step towards making this great leap in human knowledge a reality was taken at the end of October with the announcement of the winners of competitive contracts for the Mars Sample Return (MSR) mission, the second Flagship robotic mission to be proposed as part of Aurora. The parallel contracts for the Phase A studies that will carry out a full mission design iteration for the MSR have been placed with two industrial teams. One team, headed by Alenia Spazio (Italy), includes Alcatel (France), Dutch Space (Netherlands), ELV (Italy) and MDR (Canada). The other team, headed by EADS Astrium (UK), also includes Astrium SAS (France), EADS ST (France), Galileo Avionica (Italy), RAL (UK), SAS (Belgium), SENER (Spain) and Utopia Consultancies (Germany). "The industrial proposals received were of outstanding quality, reflecting the enthusiasm and the commitment of the industrial teams who prepared them," said Bruno Gardini, Aurora Project Manager. Bringing Mars back to Earth As currently envisaged, the MSR will be a two-stage endeavor. First, a spacecraft that includes a return capsule will be launched in 2011 and inserted into orbit around Mars. Then, two years later, a second spacecraft carrying a descent module and a Mars ascent vehicle (MAV) will be launched on a similar trajectory. During its final approach to Mars, the descent module/MAV will be released and make a controlled landing on the planet. A robotic drill will then collect a soil sample from a depth of 11/2 to 2 meters and seal it inside a small canister on the ascent vehicle. Other samples of martian soil and air may also be gathered and stored inside the canister. Carrying its precious samples, the MAV will lift off from the surface, then rendezvous and dock with the spacecraft in martian orbit. After receiving the canister loaded with martian rocks, the spacecraft will return to Earth with the re-entry capsule containing the samples and send it plummeting into the atmosphere. Slowed by a parachute or inflatable device, the capsule will make a fairly gentle touchdown before recovery teams retrieve the container from the landing site and deliver it to a planetary protection facility where the samples will be removed to await analysis by eager scientists. The design of the capsule will ensure that the structural integrity of the sample container remains intact, even if the parachute fails to open and a crash landing occurs. "The Mars Sample Return mission is one of the most challenging missions ever considered by ESA," said Gardini. "Not only does it include many new technologies and four or five different spacecraft, but it is also a mission of tremendous scientific importance and the first robotic mission with a similar profile to a possible human expedition to Mars." A number of the critical technologies required for the success of this ambitious endeavor have yet to be developed in Europe, e.g., re-entry of spacecraft arriving from deep space at a high velocity. As a preliminary stage in developing a vehicle capable of bringing back samples from Mars, it was considered necessary to develop this re-entry capability and to demonstrate its maturity as part of the Aurora Programme. Feasibility studies for a dedicated Arrow mission, known as the Earth re-entry Vehicle Demonstrator (EVD), were recently announced. In the same way, testing of the complex rendezvous and docking techniques will be carried out as an experiment on the ExoMars mission, the first Flagship mission of the Aurora Programme. The Phase A industrial study contracts for the ExoMars mission began in September. Contact: Bruno Gardini Aurora Project Manager ESTEC The Netherlands Phone: +31-71-565-3849 E-mail: Bruno.Gardini@esa.int Read the original news release at http://www.esa.int/export/esaCP/SEML90XLDMD_index_0.html. ________________________________________________________________________ OUR PLACE IN THE COSMOS: BIG HISTORY AND THE STORIES OF SCIENCE By Douglas Vakoch From Space.com 13 November 2003 As if college students didn't already have a hard enough time studying for their final exams, Professor David Christian has made it even harder. Most instructors of History 100 would find it ambitious enough to survey all of recorded history in a single semester, but not Christian. In his survey course at San Diego State University, history begins much earlier--by his reckoning, about 13.7 billion years earlier, going back to the Big Bang. "Normally," Christian explains, "historians look at the past on the scale of two or three centuries." With his traditional training in Russian history, this was how he began his own career as well. But ultimately, the standard approach to the past wasn't enough for him. "I got fascinated by the question, 'When is the beginning of history?'," Christian says, "and once you start asking that question, you go back and back and back. And eventually I found myself going back to the origins of the universe, because that seemed the only logical point to stop." And so, for the past fifteen years, he has taught a course on Big History, which he describes as "an attempt to look at the past on all possible time scales." Read the full article at http://www.space.com/searchforlife/seti_cosmos_vakoch_031113.html. ________________________________________________________________________ DELTA-LIKE FAN ON MARS SUGGEST ANCIENT RIVERS WERE PERSISTENT NASA/JPL release 2003-151 13 November 2003 Newly seen details in a fan-shaped apron of debris on Mars may help settle a decades-long debate about whether the planet had long-lasting rivers instead of just brief, intense floods. Pictures from NASA's Mars Global Surveyor orbiter show eroded ancient deposits of transported sediment long since hardened into interweaving, curved ridges of layered rock. Scientists interpret some of the curves as traces of ancient meanders made in a sedimentary fan as flowing water changed its course over time. "Meanders are key, unequivocal evidence that some valleys on early Mars held persistent flows of water over considerable periods of time," said Dr. Michael Malin of Malin Space Science Systems, San Diego, which supplied and operates the spacecraft's Mars Orbiter Camera. "The shape of the fan and the pattern of inverted channels in it suggest it may have been a real delta, a deposit made where a river enters a body of water," he said. "If so, it would be the strongest indicator yet Mars once had lakes." Malin and Dr. Ken Edgett, also of Malin Space Science Systems, have published pictures and analysis of the landform in today's online edition of Science Express. The images with captions are available online from the Mars Orbiter Camera team, at http://www.msss.com/mars_images/moc/2003/11/13/ and from NASA's Jet Propulsion Laboratory, Pasadena, CA, at http://photojournal.jpl.nasa.gov/catalog/PIA04869. The fan covers an area about 13 kilometers (8 miles) long and 11 kilometers (7 miles) wide in an unnamed southern hemisphere crater downslope from a large network of channels that apparently drained into it billions of years ago. "This latest discovery by the intrepid Mars Global Surveyor is our first definitive evidence of persistent surface water," commented Dr. Jim Garvin, NASA's Lead Scientist for Mars Exploration, NASA Headquarters, Washington, DC. "It reaffirms we are on the right pathway for searching the record of martian landscapes and eventually rocks for the record of habitats. Such localities may serve as key landing sites for future missions, such as the Mars Science Laboratory in 2009," continued Garvin. "These astounding findings suggest that "following the water" with Mars Global Surveyor, Mars Odyssey, and soon with the Mars Exploration Rovers, is a powerful approach that will ultimately allow us to understand the history of habitats on the red planet." No liquid water has been detected on Mars, although one of the previous major discoveries from Mars Global Surveyor pictures suggests that some gullies have been cut in geologically recent times by the flow of ephemeral liquid water. Another NASA orbiter, Mars Odyssey, has discovered extensive deposits of near-surface ice at high latitudes. Mars' atmosphere is now so thin that, over most of the planet, any liquid water at the surface would rapidly evaporate or freeze, so evidence of persistent surface water climate. Malin and Edgett estimate that the volume of material in the delta-like fan is about one-fourth the volume of what was removed by the cutting of the upstream channels. Their analysis draws on information from Mars Global Surveyor's laser altimeter and from cameras on Mars Odyssey and NASA's Viking Orbiter, as well as images from the Mars Orbiter Camera. "Because the debris in this fan is now cemented, it shows that some sedimentary rocks on Mars were deposited by water," Edgett said. "This has been suspected, but never so clearly demonstrated before." The camera on Mars Global Surveyor has returned more than 155,000 pictures since the spacecraft began orbiting Mars on Sept. 12, 1997. Still, its high-resolution images cover only about three percent of the planet's surface. Information about Mars Global Surveyor is available on the Internet at http://mars.jpl.nasa.gov/mgs. JPL, a division of the California Institute of Technology, Pasadena, manages Mars Global Surveyor for NASA's Office of Space Science in Washington. JPL's industrial partner is Lockheed Martin Space Systems, Denver, which developed and operates the spacecraft. Malin Space Science Systems and the California Institute of Technology built the Mars Orbiter Camera. Malin Space Science Systems operates the camera from facilities in San Diego. Contacts: Guy Webster Jet Propulsion Laboratory, Pasadena, CA Phone: 818-354-6278 Donald Savage NASA Headquarters, Washington, DC Phone: 202-358-1547 Ken Edgett Malin Space Science Systems, San Diego, CA Phone: 858-552-2650 x500 Additional articles on this subject are available at: http://www.astrobio.net/news/article673.html http://www.space.com/scienceastronomy/mars_water_031114.html ________________________________________________________________________ EXTRATERRESTRIAL RESOURCES: "LIVING OFF THE LAND" By Leonard David From Space.com 14 November 2003 Outer space has an endless supply of resources. Within rocket's reach there are light buckets full of intense solar energy, at least out to Mars. Then there are valuable materials on the Moon, as well as on Mars and its moons. Near Earth asteroids offer yet another mother lode of minerals. At present, the vast gulf of space prohibits access to these treasures, but a loosely knit group of like-minded experts believe that by tapping the rich resources of space, humanity's foothold on other worlds will be far more secure and long-lived. Mining specialists, space engineers, and energy strategists were among those gathered at Space Resources Roundtable V, held here October 28-30 at the Colorado School of Mines. Also giving space resource mining its "due diligence" were lawyers. Turns out you can't leave Earth without them. Read the full article at http://www.space.com/businesstechnology/technology/space_resources_03111 4.html. ________________________________________________________________________ LIFE'S RECIPE CARD Based on a DOE report From Astrobiology Magazine 14 November 2003 Scientists announced significant progress toward creating an artificial organism that one day may have uses ranging from pollution control to clean energy production. Scientists using commercially available DNA took only two weeks to build from scratch an artificial virus with the identical genetic code of a simple virus already known to infect and kill bacterial cells. The research at the Institute of Biological Energy Alternatives in Rockville, MD, was detailed in a paper to be published in the Proceedings of the National Academy of Sciences and at a news conference by the Energy Department, which funded the three-year research effort. While the project was based on widely known molecular biology principles, the breakthrough was in the short time--days instead of months or years--it took to construct the virus, said institute founder J. Craig Venter, one of the lead researchers. Researchers previously synthesized the polio virus from enzymes that naturally occurred in cells, but that process took three years and produced viruses with defects. The effort last summer by Venter and his colleagues took only two weeks from start to finish and created a viral DNA identical to the known genetic code, the researchers said. The team used enzymes to glue the oligonucleotides together accurately into the complete 5,386-base genetic strand, and to copy it many times. The synthetic virus "had the ability to infect and kill bacterial cells," the authors wrote in the paper. Even though the experiment involved a simple organism, the researchers suggested their work demonstrated the ability to quickly and accurately synthesize long segments of DNA that can serve as "a stepping stone to manipulating more complex organisms." At a news conference, Energy Secretary Spencer Abraham called the accomplishment "an extraordinary and exciting development" that will speed up "our ability to develop biology-based solutions for some of our most pressing energy and environmental challenges." As a result of the scientists' progress, Abraham said it is now "easier to imagine in the not-too-distance future a colony of specially designed microbes living within the emission-control system of a coal-fired plant, consuming its pollution and its carbon dioxide, or employing microbes to radically reduce water pollution or to reduce the toxic effects of radioactive water." Their project is part of a three-year, $3-million (U.S.) Energy Department grant, to create a single-celled organism with the minimum number of genes necessary to sustain life. To begin the plan, computer simulations attempted to mimic what genetic starting materials might be needed for life, mainly feeding, reproduction, and death. Eventually in a petri dish, their experiment would then have spawned a new human-made species on Earth. For astrobiologists, such a prospect offers up an intriguing kind of milestone--one not unlike how first creating amino acids from simpler biochemicals shaped the subsequent origin of life debate. As the Astrobiology Roadmap for this new field states: "A golden age has begun for the life sciences, an age in which science and technology will benefit enormously from a fundamental understanding of the full potential of living systems... This is an agenda for inspiring the next generation of planetary explorers and stewards to sustain the NASA vision and mission." NASA's Astrobiology Institute has recently initiated a Working Group specifically devoted to studying the role of viruses and primordial life. The molecular definition of life Several years ago, Venter first looked at a mycoplasma as the best such model, because the organism is a record-holder of sorts: the self- replicating life form with the smallest known complement of genetic material. Unlike the human genome with its 30,000 to 50,000 genes, M. genitalium gets by with only 517. But remarkably, nearly half of even that minimal set is extra baggage. Under some laboratory conditions, as few as 300 of the genes can fulfill its definition as a lifeform that feeds and divides. As it turns out, what is the definition of life itself? and also exactly what is its minimal genetic set? have been hotly contested. Gene size is one of the main limits to what could be the final and minimal cell size, and thus may set a limit on possible targets for creating life from scratch. But what structures are too small or too simple to be considered "life"? To answer this question, NASA earlier asked the National Research Council of the National Academy of Sciences to convene an expert panel. It met in late 1998 and published the report, "Size Limits of Very Small Micro-organisms." Some scientists believe that life can be very small indeed. If mycoplasma's small gene set is too challenging for laboratory "synthesis", then there are even more radical choices to consider. Called nanobes, nanobacteria, or nano-organisms, these miniscule structures borrow their name from their unit of measurement, the nanometer. A nanometer is one billionth of a meter. That's about the length of 10 hydrogen atoms laid out side by side. The period at the end of this sentence is approximately one million nanometers in diameter. While the tiniest bacteria measure 200 nanometers across, nanobes are even smaller. They can range anywhere from 20 to 150 nanometers long. "The limit adopted by biologists is 200 to 250 nanometers on the basis that [the structures] must be large enough to contain a DNA or RNA strand, and have the ribosomes, etc., necessary to carry on metabolism," said Robert Folk of the University of Texas at Austin. "My opinion is that scientists do not know enough to set arbitrary limits on life. After all, pre-Pasteur, nobody even thought there were things such as germs, and pre-1890 nobody knew there were viruses." Century of struggle and discovery The Latin name itself for virus means "poison". The collection labs have identified thousands (approximately 3500) so far. The basic modus operandi of a virus is to take over another organism's cellular machinery. The virus thus ties its fate intimately with the internal-- and not external--ecosystem of another species. Since the first virus was isolated one-hundred and eleven years ago (1892, by Russian Dimitrii Ivanovsky), the number of questions centering on their transmission and lifecycle seem to have ballooned: how do viruses move from host-to-host, how does the host's immune system try to check their replication, and even more simply, what do they look like? One question that arises in this context but without consensus is whether viruses are living at all--or just living with us? The problem with this question is how one defines life. Viruses do seemingly have "a plan", thus satisfying the earliest definitions for life offered by Aristotle. Viruses do furthermore offer a surprising and radical set of Darwinian choices; indeed high mutation rates are often credited with their robust survival strategies. A clean separation of viruses from the continuum of biochemistry seems unlikely. There is evidence that human DNA has many viral vestiges, thus elevating the virus kingdom to much more than some kind of biological passenger status. From generation to generation, viruses have introduced new genetic information into their victims and hosts. The debate on defining life rarely has reached scientific consensus, despite volumes written cataloguing the various qualifications for being "alive". Of note however, the presence of similar molecules like DNA and RNA, even in the simplest life forms like viruses, is often suggestive of a single origin event--or at least, a whittling away of inferior encoding molecules from a multitude of less fit alternatives. What's next? To continue this research, Venter's recipe is not entirely one constructed from scratch. First all genetic material will be removed from an existing organism called Mycoplasma genitalium, a tiny organism that lives in human genital tracts. The 25-person research team led by Venter and Smith will then synthesize an artificial string of genetic material, resembling a naturally occurring chromosome. If the project goes according to their outline, this basic biochemical soup will then contain the minimum number of M. genitalium genes needed to sustain life. By first "gutting" their mycoplasma to its minimal genetic needs, they will then try to stitch the pieces back together and see if they can reassemble the whole. A hollowed-out cell membrane will encase the simplified chromosome, and its basic life-sustaining capabilities will become the new and never-before-seen organism. But Venter, among the scientists who first produced a map of the complete human genetic code, said much research is needed to produce such a significantly larger artificial organism. "It's an interim step. Now we have the enabling technology to take us to these next exciting frontiers," Venter said. For now, "This is basic science at the most basic level with lots of unknowns." Still, he said, "the ability to construct synthetic genomes may lead to extraordinary advances in our ability to engineer microorganisms for many vital energy and environmental purposes." Venter said all the research details would be included in the paper to be published in the scientific journal and that at this time, his company has no plans to file for any patents. Read the original article at http://www.astrobio.net/news/article674.html. ________________________________________________________________________ ARECIBO DIARIES: ONCE MORE INTO THE BREACH! By Peter Backus From Space.com 14 November 2003 "Deployment" is the term we use at the Institute for what is perhaps our most enormous undertaking, Project Phoenix observing. That the word derives from the language of warfare seems all too appropriate sometimes. We make complex plans for transporting personnel and equipment across many miles, so that the right people and equipment arrive at the right place and time for best effect. Some of both remain behind the line--the people remain to provide support, the equipment we hold in reserve "just in case." Fortunately for our personnel battle fatigue is temporary, limited to the weariness from nine hours of flying and jet lag from jumping four time zones. With a good night's sleep and a delicious café con leche from the Observatory cafeteria, the troops were ready for the boxes. Read the full article at http://www.space.com/searchforlife/seti_arecibo_backus_031114.html. ________________________________________________________________________ DAMAGED JAPANESE SPACECRAFT MIGHT CONTAMINATE MARS IF IT HITS From SpaceDaily 14 November 2003 Japan's leading national daily the Yomiuri Shimbun is reporting that the ill fated Nozomi explorer that is Japan's first Mars probe, is expect to crash into the red planet on December 14 if it remains on its current course. According to officials at the newly formed Japan Aerospace Exploration Agency (JAXA)--the operating agency--the Institute of Space and Astronautical Science is urgently investigating how to avoid the impact. The mission which has cost some $US200 million can no longer carry out its mission in any form and the priority now is to dispose of the spacecraft safely and avoid any potential contamination of Mars with any Earth microbes still on the spacecraft. As Nozomi was only intended to be a Mars orbiter it's decontamination program was virtually non- existent compared to the full scrub downs Britain Beagle 2 lander and the U.S. twin rovers were subjected to, under agreed protocols formulated by the National Academy of Sciences in Washington DC. Read the full article at http://www.spacedaily.com/news/mars-life- 03k.html. ________________________________________________________________________ SKEPTICISM WITH WONDER: INTERVIEW WITH CAROL OLIVER From Astrobiology Magazine 17 November 2003 Among astrobiologists, the past few years have witnessed marvelous findings--and some skepticism: the discovery of planets around other stars, strong circumstantial evidence for a liquid water ocean beneath the surface of Jupiter's moons Europa, Ganymede, and Callisto, controversial claims for biological activity in a martian meteorite, the discovery of life in extreme terrestrial environments, and a genuine revolution in our understanding and manipulation of the genetic mechanisms of the living cell. As Dr. Bruce Runnegar, Director of NASA's Astrobiology Institute, summarized, this scientific horizon is challenging: "Where did we come from? How did we originate? ...astrobiology is something that any civilization worth its salt should do, provided it can afford to do so." Communicating the importance of these results has attracted the interest of a wider academic community, in an attempt to understand how to educate ourselves, while also unifying both our own skepticism and wonder. Astrobiology Magazine had the chance to talk with Carol Oliver, Executive Officer of the Australian Centre for Astrobiology, about the challenges and opportunities for communicating this new science of astrobiology. Astrobiology Magazine (AM): You did a formative interview with Carl Sagan in late 1980's. When we interviewed his widow, Ann Druyan, about why Dr. Sagan was so effective, she remarked that he "reunified skepticism with wonder-and never one at the expense of the other, but always in equal parts." How does that conclusion meet up with your own experience in person, and also with the way you have seen other science communicators go about this difficult problem? Carol Oliver (CO): My experience has largely been that scientists have interesting things to say, but in a one-dimensional way bereft of the wonder that captures the imagination. Carl Sagan knew how to do both, as Ann Druyan remarks. He did this with a breathtaking technique in driving the interview to convey what he wanted to say and largely whether the reporter asked the right questions or not. My memory of that interview was of a man brimming over with the desire to share his passion science. In some respects he was way ahead of his time. He talked to me then of his hopes that the superpowers would get together and build a huge space ship in low Earth orbit to take people to Mars--remember this was in Cold War days. Well, we got the International Space Station and maybe Sagan's Mars spaceship will get built too at some point in the future. I've seen other science communicators use a number of different techniques to connect with the public, for example, using everyday analogies and well constructed easy-to-read prose to explain complex concepts. Paul Davies uses funny little stick men in his PowerPoint presentations that immediately puts the audience at ease. Seth Shostak of the SETI Institute recently captured the undivided attention of a hall full of European students by using humor and analogy. The common thread is that good science communicators are as passionate about communication as they are the science. It comes through, and audiences are swept up in this passion that carries them across this scary area called science. AM: Ann Druyan also said that he paid for his efforts at communicating to the general public, with his colleagues. But went on anyway, under the premise that "if science was a kind of preserve of the privileged few, then even the little democracy that we have would be jeopardized. He saw it as an act of citizenship." Would you agree first that scientists are reluctant to get into research topics in a public way, and secondly that science communication is part of preserving a democracy since we all depend so much on the results of science and technology, say, even to vote? CO: Yes indeed he did. Good science communicators still suffer from it. Peers tend view translating science into something public audiences can appreciate somehow trivializes science. In Australia it is even worse--a scientist who dares to communicate risks being pilloried for "big-noting" him or herself. It may be the same in the U.S. and elsewhere. Those who become good science communicators are usually in a position that is out of reach of this dinosaur and self-defeating attitude. Shostak, for example, benefits from being part of an organization that recognizes his talent as a science communicator and encourages it--that doesn't happen in the academic environment. Scientists usually have no training in public communication. They are sometimes thrust in front of the media by well-meaning press officers--the expectation being they can easily translate their work into common language. I've seen puzzlement on how to do this. One scientist once asked me the best way to convey the process of science in a 30-second sound bite! Is science communication part of preserving democracy? Perhaps--but the real issue is whether public audiences have the critical thinking necessary to participate in either science communication or democracy. Sagan said in the last book before his death in 1996 "The Demon-Haunted World" that both were impossible without understanding the scientific method and the critical thinking that comes with that. It's clear that is in woefully short supply with more than half the U.S. public believing we're being regularly visited by beings from other worlds. AM: From your experience, in retrospect, what is your opinion of the communication strategy that surrounded the martian meteorite finding, the Allen Hills meteor result? CO: I actually think this was a good strategy. NASA brought in the skeptics and called the press conference as soon as it was clear there was a leak of the news. The fact that the media was speculating the night before the press conference only added to the focus. I don't think there was anything the strategists could have done about the caveats being left out--particularly with the Presidential announcement, which perhaps added to the public perception that past life on Mars had been discovered. I don't think subsequent criticisms have done any damage at all--in fact perhaps it has helped generate public opinion that supports further studies of Mars. It's not a done deal and I believe the public understands that and why there is the need to continue the search for the answer to questions on whether life exists on Mars today or existed at some point deep in its archean history. Together with the discovery of extrasolar planets ten months earlier, the Allen Hills meteorite probably laid the ground for astrobiology as we see it today. AM: Similarly, what is your opinion of the way SETI@home is able to communicate and put science in the hands of millions of people directly? CO: I think SETI@home is a fun thing to do, with the potential for some good science. Some researchers are doubtful about the value of the project and worry if nothing is detected using this technique in, say, ten years. I think these critics miss the point. It's okay to have some fun, especially when there is some good science being done at the same time. It definitely is better than flying toasters. SETI@home also assists in raising the profile of SETI--and offers the potential to make SETI a household name. AM: Many of our essayists, such as Oliver Sacks, have talked about early formative experiences with science fiction like HG Wells as informing their interest in astrobiology. Can you comment from your research if you believe science fiction has any role in shaping interest, and what its limits or strengths might be? CO: I've no evidence that science fiction shapes our thinking about science--but it seems obvious that it must. Mars in particular has fired the imaginations of science fiction authors--Edgar Rice Burroughs, Ray Bradbury, and Kim Stanley Robinson. Oliver Morton says in his book "Mapping Mars" that the arrival of humans on Mars will not be the dawn of a new era, but a chapter in an ongoing novel. I think that is right. We've already been there, many times, in our literature. So the key strength is in the ability to envision a vista of red rocks, valleys and craters through our culture, without even stepping onto the red planet--virtual visits of the imagination. On the other hand the Hollywood depiction of aliens is often banal and improbable, as in Independence Day. Perhaps that doesn't do any favors for astrobiology. Star Trek is an interesting kettle of fish--it has been predictive of many things. Compare cell phones with the Enterprise communicators from 1966, for example, and witness the books that delve into the "science of Star Trek". On the downside it has shrunk the cosmos to something our minds can manage instead of underscoring the reality of the gaping chasm between the Sun and even the nearest stars, and encouraged the belief that if communicating extraterrestrial civilizations are out there they look approximately like us and speak perfect English. Overall though, I believe science fiction fires the imagination and partly drives our curiosity. We want to go there and know what it is really like rather than rely entirely on the limitations of robot probes. AM: You completed a thesis entitled "SETI and the Media: Improving Science Communication"--what are its general findings regarding the good and bad ways this field has been shaped in popular media? CO: Governments and institutions promote the concept that more and better science news will address a serious problem--the very high science illiteracy rate among adult populations. This approach is flawed for several reasons. But the bottom line is that to expect the media to provide lessons on science literacy is like expecting a newspaper to contain instructions on how to read it. (The latest National Science Foundation's Science and Engineering Indicators suggests that in the U.S. that is running at 75% of the adult population--that means three out of every four citizens are probably unable to either fully understand a news piece on astrobiology or any other science. More than half the U.S. public, for example, absolutely believes the universe is teeming with intelligent life--and they are visiting us on a regular basis. In Europe it is not that much better. According to the Eurobarometer 55.2 survey around 50% of the adult population suffer from science illiteracy. The survey found, for example, that more than 25% of the public believes the Sun goes around the Earth--where does that leave attempts to convey astrobiology to adult audiences? There are three clear reasons why more and better science news won't fix this: 1. There is no survey data in the past 50 years of science communication on how public audiences make sense of science stories in the media. 2. The measure used for science illiteracy is questionable. 3. The mass media does not educate, it informs--the subtle difference means understanding only happens serendipitously.) Astrobiology is a fast emerging science in an age where the Internet is rapidly changing the face of science communication across formal and informal education, media, scientific publications and public opinion in a dynamic two-way communication multi-media environment. Globally, more than half a billion people are now connected. In the U.S., 9% of the NSF survey respondents said the Internet served as their primary source of science information and the Eurobarometer survey, 16%. It appears a major paradigm shift is required in order to make any significant improvement in science communication. We need to understand more clearly how to engage public audiences and across multiple communication platforms--astrobiology has all the elements already and the potential to lead the change in approach for science communication in general. The SETI Institute made a very interesting case study because of the cultural nature of its SETI experiment--it forced the Institute to think about public communication and education as an integral part of the research at an early stage rather than an "add-on", which is the way I think it should be. The science teachers I've spoken with largely feel totally disconnected from cutting edge research--how then can they inspire our children with limited and often out of date resources? (I'm currently putting together a proposal for a new NASA Astrobiology Institute Science Communication Focus Group--these are groups of experts inside and outside the NAI, focused on a particular element of astrobiology such as Mars. A band of experts experienced in communicating astrobiology is being brought together to tackle the issues I've mentioned. They are science journalists, science communicators, science educators, science museum experts, science web specialists, science TV producers and other related experts. I'm not sure such a multi-communication group has been brought together before. They are mostly U.S. based, but some from the UK, Europe and Australia. Science communication is a global thing. I expect good outcomes.) AM: Some have argued that a detectable SETI event would be the greatest challenge to media communication ever. And numerous organizations like the Planetary Society have outlined strategies for how to communicate such news. Can you comment on what you believe might be an effective strategy there? CO: People resources are SETI's greatest weakness in the event of a detection. A SETI colleague aptly points out that a single large supermarket could barely get full staffing using the entire global community of professional SETI researchers. Media is not going to be their priority in a potential detection--confirming the signal will be. A close second is that SETI researchers are scattered around the world mostly in small independent groups that have no effective communication system between the groups that would work in the media demands of a potential detection. The challenge for SETI is in marshalling these people resources to enable a credible, timely response to the media-- which almost certainly won't happen in a nice ordered press conference type of way because there is no secrecy attached to SETI. A third problem in thinking about how to manage this is that with researchers expecting it to be a long-haul project, how do you encourage planning now? This is also a challenge, and one I've been aware of at an international level for some years. Most of my science journalist friends are incredulous when I tell them there is no international SETI media plan to respond to a promising detection. I'm hopeful that will change. AM: Working from Australia now, but having spent time in the U.S. and UK, do you believe that at least English-speaking media has much commonality in how they handle science and how new findings trickle into the public consciousness? CO: There is some commonality, but the reception environment is culturally and socially very different. For example, in the UK there is a high level of public mistrust in government and science. This is a country crippled by both Mad Cow Disease (BSE) and public suspicion of genetically modified crops. In the U.S. you have Roswell, Area 51 and extraterrestrials buzzing the countryside after their long-haul flights from the stars--remember half the U.S. public believes this. In the UK, Britons are demanding a voice in science research. Astrobiology researchers should not think they are immune to such a backlash, as remote a possibility as that seems. Missions that bring back samples from comets, asteroids and eventually Mars are not that far away. Organics means life in the public mind, and that raises the spectre of a War of the Worlds in reverse. Remember it was an Earthly bug that got the Martians in the end, not the bombs. Risk communication planning isn't taken as nearly as seriously in science as it is in the corporate world. The Cassini mission [a 1997 nuclear-fueled probe to Saturn] proved that stance is an error of judgement. Of course the public are concerned, even when scientists view the risk as virtually zero to none. Read the original article at http://www.astrobio.net/news/article678.html. ________________________________________________________________________ NEW ADDITIONS TO THE ASTROBIOLOGY INDEX By David J. Thomas http://www.lyon.edu/projects/marsbugs/astrobiology/astrobiology.html 18 November 2003 Astrobiology and planetary engineering articles http://www.lyon.edu/projects/marsbugs/astrobiology/online_articles1.html Astrobiology Magazine, 2003. Skepticism with wonder: interview with Carol Oliver. Astrobiology Magazine. B. E. DiGregorio, 2003. The calm before the storm: an interview with Dr. Gilbert Levin. SpaceDaily. Terrestrial extreme environments articles http://www.lyon.edu/projects/marsbugs/astrobiology/online_articles2.html Illinois State Water Survey, 2003. World's most alkaline life forms found near Chicago. SpaceDaily. R. Kunzig, 2003. Deep-sea biology: living with the endless frontier. Science, 302(5647):991 NASA Ames Research Center, 2003. Mars-like Atacama Desert could explain Viking no life results. SpaceDaily. NASA Ames Research Center, 2003. Mars-like desert could explain Viking 'no life' results. Spaceflight Now. National Research Council, 2003. Exploration of the Seas: Voyage into the Unknown. National Academies Press, Washington, DC. R. Navarro-Gonzalez, F. A. Rainey, P. Molina, D. R. Bagaley, B. J. Hollen, J. de la Rosa, A. M. Small, R. C. Quinn, F. J. Grunthaner, L. Caceres, B. Gomez-Silva and C. P. McKay, 2003. Mars-like soils in the Atacama Desert, Chile, and the dry limit of microbial life. Science, 302(5647):1018-1021. Human space exploration articles http://www.lyon.edu/projects/marsbugs/astrobiology/online_articles3.html L. David, 2003. Extraterrestrial resources: "living off the land". Space.com. SETI articles http://www.lyon.edu/projects/marsbugs/astrobiology/online_articles4.html P. Backus, 2003. Arecibo diaries: once more into the breach! Space.com. L. David, 2003. Keeping watch for interstellar computer viruses. Space.com. S. Shostak, 2003. Location, location: Puerto Rico is listening. Astrobiology Magazine. Evolution (biological, chemical and cosmological) articles http://www.lyon.edu/projects/marsbugs/astrobiology/online_articles5.html E. DeVore, 2003. Voyages Through Time(tm)--a new way to teach science. Space.com. J. M. García-Ruiz, S. T. Hyde, A. M. Carnerup, A. G. Christy, M. J. Van Kranendonk, N. J. Welham, 2003. Self-assembled silica-carbonate structures and detection of ancient microfossils. Science, 302:1194- 1197. A. I. Miller and M. Foote, 2003. Increased longevities of post- Paleozoic marine genera after mass extinctions. Science, 302(5647):1030-1032. L. Mullen, 2003. Worms in the mist. Astrobiology Magazine. Pennsylvania State University, 2003. Hydrogen sulfide, not carbon dioxide, may have caused largest mass extinction. SpaceDaily. B. Rasmussen, S. Bengtson, I. R. Fletcher, and N. J. McNaughton, 2002. Discoidal impressions and trace-like fossils more than 1200 million years old. Science, 296:1112-1115. L. J. Siegel, 2003. Preemies from the Precambrian. Astrobiology Magazine. U.S. Department of Energy, 2003. Life's recipe card. Astrobiology Magazine. University of Washington, 2003. The suffocating age. Astrobiology Magazine. Planetary protection articles http://www.lyon.edu/projects/marsbugs/astrobiology/online_articles6.html D. H. Grinspoon, 2003. Space invaders. Astrobiology magazine. SpaceDaily, 2003. Damaged Japanese spacecraft might contaminate Mars if it hits. SpaceDaily. Extrasolar planets articles http://www.lyon.edu/projects/marsbugs/astrobiology/online_articles7.html L. Stiles, 2003. Nearby star is forming a Jupiter-like planet. Universe Today. Astrobiology and extreme environments book list http://www.lyon.edu/projects/marsbugs/astrobiology/astrobiology_books.ht ml National Research Council, 2003. Exploration of the Seas: Voyage into the Unknown. National Academies Press, Washington, DC. ________________________________________________________________________ CASSINI SIGNIFICANT EVENTS NASA/JPL releases 30 October - 5 November 2003 The most recent spacecraft telemetry was acquired from the Goldstone tracking station on Wednesday, November 5. 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. On-board activities this week included Radio and Plasma Wave Science (RPWS) high frequency receiver calibrations, uplink of an RPWS Instrument Expanded Block (IEB) load test, a command to halt the Cosmic Dust Analyzer (CDA) IEB in slot 2, a Magnetospheric Imaging Instrument data rate throttle down, and execution of an X-band body vector table update. The University of Iowa has released additional information regarding RPWS recordings of the sound of one of the largest solar flares seen in decades as it moved outward from the sun. The radio wave burst was recorded Tuesday, October 28, by Cassini. The radio waves, moving at the speed of light, took just 69 minutes to reach the spacecraft, currently some 8.7 Astronomical Units (AU) distant from Earth. One AU is approximately 150 million kilometers. Port #1 analysis of the Science Operations Plan Implementation for tour sequences S05 and S06 was completed. A number of problems were found that will need to be resolved by the final input port in mid November. The Program conducted the Saturn Orbit Insertion (SOI) Risk Review on Thursday, 10/30. This was an external review convened to assess the risks and risk mitigation measures associated with a successful Saturn orbit insertion. The board was comprised of independent reviewers from JPL, other NASA agencies, industry, and private consultants. Closing comments from the board were very positive. All teams and offices participated in this month's NASA Quarterly Review. An informal peer review was held for the Cassini Archive Tracking System (CATS). Software design and technologies were discussed with representatives from JPL's section 382 and the Planetary Data System who made recommendations to the development team. Visual and Infrared Mapping Spectrometer personnel conducted a ground acceptance test of their instrument flight software version 8.1. The spectral summing capability worked flawlessly. Regression testing will now begin. The Multi Mission Image Processing Laboratory reprocessed many Imaging Subsystem (ISS) Narrow-angle calibration files from pre-launch data. A correction step was added to eliminate anti-blooming artifacts that won't show up in flight data. The reprocessed data have been delivered to the ISS Science Team. CDA flight software V 9.2.0 was delivered to the project software library. Preliminary Alf_Tool checks indicate no errors. A Software Requirements and Certification Review is to be scheduled in mid-November with an uplink date set for mid-January 2004. A Delivery Coordination Meeting was held for Spacecraft Operations Office (SCO) Solaris 9 tools. Most of the items being delivered were ports of existing tools to the new operating system. The delivery included Propulsion Tools V3.0, High Gain Antenna Tools 10.0, Maneuver Automation Software 4.0, MPLOT 1.6, and Telecom Forecaster Predictor 3.2. Bookmarks announcing Cassini's elementary school education program "Reading, Writing, and Rings" are available through the Cassini Outreach Office for distribution at education conferences and classrooms. Both Spanish and English versions are available. 6-12 November 2003 On-board activities this week included transition to Reaction Wheel Control in preparation for Gravitational Wave Experiment (GWE) #3, ACS X-Band body vector update, and biasing of the reaction wheels. Instrument activities included a Radio and Plasma Wave Science (RPWS) high frequency receiver calibration, Imaging Science Subsystem (ISS) data compression check, Ultraviolet Imaging Spectrograph solar port calibration and bright star observation, Composite InfraRed Spectrometer flight software upload to the solid state recorder, Ion and Neutral Mass Spectrometer power on, pressure test, memory dump and power off, and an eight day RPWS Saturn orbit insertion instrument expanded block test. As part of this week's activities, ISS successfully acquired 100 star images and 393 Saturn images. The Multi Mission Image Processing Laboratory automated downlink subsystem processed and delivered these to the ISS Science Team at SSI at a rate of 3 seconds/image. The Radio Science Subsystem (RSS) Gravitational Wave Experiment (GWE) #3 started on the evening of November 9 over Goldstone's DSS-25 station. The experiment will continue for 20 days with continuous DSN support. The spacecraft will remain on reaction wheel control for the duration of the experiment. The Ka-band transmitter at DSS-25 has been restored to operations, although at a lower output power, and without redundancy. The DSN engineers are working towards returning it to the nominal 800 Watts in the future. Development of the C42 background sequence is on track. The merged products for the Preliminary Sequence Integration and Validation (PSIV) cycle 1 phase have been released. As there have been no changes to the DSN allocation file, and simulation of the sequence is not required, the PSI&V Science Allocation Panel, Simulation Coordination, and Simulation Procedure Review meetings were cancelled. Preliminary port1 for the Science Operations Plan Implementation process was reached for tour sequences S19 and S20, and preliminary port 2 for S05 and S06. Official ports were reached for two sequences as part of the Science Planning Team process. C43 passed its third and final port with the merged product currently being run through Kinematic Prediction Tool (KPT)/ Inertial Vector Propagator (IVP). C44 reached its first official port. The product was merged and delivered to ACS for KPT/IVP analysis. A Project Software Monthly Management Review was held to review status of Spacecraft Operations Office and Uplink Operations tools. Development continues on schedule. A Delivery Coordination Meeting was held for Mission Planning's version 5.1 of AP_DOWNLINK. 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. ________________________________________________________________________ MARS GLOBAL SURVEYOR IMAGES NASA/JPL/MSSS release 30 October - 12 November 2003 The following new images taken by the Mars Orbiter Camera (MOC) on the Mars Global Surveyor spacecraft are now available. Valley Floor (Released 30 October 2003) http://www.msss.com/mars_images/moc/2003/10/30/index.html Isidis Planitia (Released 31 October 2003) http://www.msss.com/mars_images/moc/2003/10/30/index.html Defrosting Scene (Released 01 November 2003) http://www.msss.com/mars_images/moc/2003/11/01/index.html Frosty Wind Streaks (Released 02 November 2003) http://www.msss.com/mars_images/moc/2003/11/02/index.html Tharsis Wind Streaks (Released 03 November 2003) http://www.msss.com/mars_images/moc/2003/11/03/index.html Olympica Fossae (Released 04 November 2003) http://www.msss.com/mars_images/moc/2003/11/04/index.html Gullies in Nirgal (Released 05 November 2003) http://www.msss.com/mars_images/moc/2003/11/05/index.html All of the Mars Global Surveyor images are archived at http://www.msss.com/mars_images/moc/index.html. Cracked and Pitted Plain (Released 06 November 2003) http://www.msss.com/mars_images/moc/2003/11/06/index.html Sand Dunes in Hellas (Released 07 November 2003) http://www.msss.com/mars_images/moc/2003/11/07/index.html Circular Mesa (Released 08 November 2003) http://www.msss.com/mars_images/moc/2003/11/08/index.html Valley near Olympus (Released 09 November 2003) http://www.msss.com/mars_images/moc/2003/11/09/index.html South Polar Patterns (Released 10 November 2003) http://www.msss.com/mars_images/moc/2003/11/10/index.html Dust Devil Art (Released 11 November 2003) http://www.msss.com/mars_images/moc/2003/11/11/index.html Ius Chasma Layers (Released 12 November 2003) http://www.msss.com/mars_images/moc/2003/11/12/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. Additional articles on this subject are available at: http://spaceflightnow.com/news/n0311/04merrovers/ http://www.universetoday.com/am/publish/mars_rover_will_be_okay.html ________________________________________________________________________ MARS ODYSSEY THEMIS IMAGES NASA/JPL/ASU release 3-14 November 2003 Battered Terrain of Amenthes (Released 3 November 2003) http://themis.la.asu.edu/zoom-20031103a.html Layers and erosion and more layers (Released 4 November 2003) http://themis.la.asu.edu/zoom-20031104a.html Layers in Meridiani Planum (Released 5 November 2003) http://themis.la.asu.edu/zoom-20031105a.html Devil's Den in Terra Sirenum (Released 6 November 2003) http://themis.la.asu.edu/zoom-20031106a.html Sand and Water (Released 7 November 2003) http://themis.la.asu.edu/zoom-20031107a.html Dust and Sand Mixing (Released 10 November 2003) http://themis.la.asu.edu/zoom-20031110a.html Aureum Chaos (Released 11 November 2003) http://themis.la.asu.edu/zoom-20031111a.html Cutting Craters (Released 12 November 2003) http://themis.la.asu.edu/zoom-20031112a.html Canyons of Aeolis Mensae (Released 13 November 2003) http://themis.la.asu.edu/zoom-20031113a.html Mars in True Color (almost) (Released 14 November 2003) http://themis.la.asu.edu/zoom-20031114a.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. ________________________________________________________________________ MARS ROVER SPIRIT MISSION STATUS NASA/JPL release 2003-144 4 November 2003 A series of tests of one of the science instruments on NASA's Mars Exploration Rover Spirit has enabled engineers and scientists to identify how to work around an apparent problem detected in August. Tests now indicate that all of the science instruments on both Spirit and its twin, Opportunity, are in suitable condition to provide full capabilities for examining the sites on Mars where they will land in January. Spirit's Mössbauer spectrometer, a tool for identifying the types of iron-bearing minerals in rocks and soil, returned data that did not fit expectations during its first in-flight checkup three months ago. A drive system that rapidly vibrates a gamma-ray source back and forth inside the instrument appeared to show partial restriction in its motion. "The drive system is adjustable. We can change its velocity. We can change its frequency," said Dr. Steve Squyres of Cornell University, Ithaca, NY, principal investigator for the rovers' science instruments. "We've found a set of parameters that will give us good Mössbauer science if the instrument behaves on Mars the way it is behaving now." The corrective countermeasures include using a higher frequency of back- and-forth motion. "With these settings, whatever happened during launch will not decrease the quality of the data we get from the instrument," said Dr. Göstar Klingelhöfer, of Johannes Gutenberg University, Mainz, Germany, lead scientist for the Mössbauer spectrometers on both rovers. "The instrument was designed with enough margin in its performance that we can make this change with no significant science impact." A possible explanation for the instrument's behavior since launch is that intense vibration of the spacecraft during launch shook something inside the spectrometer slightly out of position, he said. Landings on Mars are risky. Most attempts over the years have failed. And even if the spacecraft survives the landing, there is the potential that individual components could be damaged. "One remaining issue with the Mössbauer Spectrometer on Spirit, as with all the instruments, is that we can't be one hundred percent sure it'll operate on Mars the way it's operating now," Squyres said. "We'll breathe easier once we've done all our post-landing health checks." Another fact that has emerged from the in-flight checkouts of the Mössbauer spectrometers on both spacecraft is that the internal calibration channel of the Mössbauer spectrometer on Opportunity is not functioning properly. But because the instrument has the redundancy of a separate, completely independent external calibration method, this problem will not hamper use of that instrument, Squyres said. Spirit is on course to arrive at Mars' Gusev Crater at 04:35 January 4, 2004, Universal Time, which is 8:35 PM January 3, Pacific Standard Time and 11:35 PM January 3, Eastern Standard Time. (These are "Earth received times," meaning they reflect the delay necessary for a speed- of-light signal from Mars to reach Earth; on Mars, the landing will have happened nearly 10 minutes earlier.) Three weeks later, Opportunity will arrive at a level plain called Meridiani Planum on the opposite side of Mars from Gusev. Opportunity will search for the history of water there, key information for assessing whether the site ever could have been hospitable to life. As of 13:00 Universal Time on November 5 (5:00 AM PST, 8:00 AM EST), Spirit will have traveled 367.4 million kilometers (228.3 million miles) since its launch on June 10 and will still have 119.6 million kilometers (74.3 million miles) to go before reaching Mars. Opportunity will have traveled 296 million kilometers (184 million miles) since its launch on July 7 and will still have 160 million kilometers (99.2 million miles) to go to reach Mars. The Jet Propulsion Laboratory, a division of the California Institute of Technology, manages the Mars Exploration Rover project for NASA's Office of Space Science, Washington, DC. Additional information about the project is available from JPL at http://mars.jpl.nasa.gov/mer and from Cornell University, Ithaca, NY, at http: