MARSBUGS: The Electronic Astrobiology Newsletter Volume 9, Number 5, 4 February 2002. Editors: Dr. David J. Thomas, Science Division, Lyon College, Batesville, AR 72503-2317, USA. dthomas@lyon.edu Dr. Julian A. Hiscox, School of Animal and Microbial Sciences, University of Reading, Reading, RG6 6AJ, United Kingdom. J.A.Hiscox@reading.ac.uk Marsbugs is published on a weekly to monthly basis as warranted by the number of articles and announcements. Copyright of this compilation exists with the editors, except for specific articles, in which instance copyright exists with the author/authors. While we cannot copyright our mailing list, our readers would appreciate it if others would not send unsolicited e-mail using the Marsbugs mailing list. The editors do not condone "spamming" of our subscribers. Persons who have information that may be of interest to subscribers of Marsbugs should send that information to the editors. E-mail subscriptions are free, and may be obtained by contacting either of the editors. Information concerning the scope of this newsletter, subscription formats and availability of back-issues is available from the Marsbugs web page at http://welcome.to/marsbugs or http://www.lyon.edu/webdata/users/dthomas/marsbugs/marsbugs.html. _____________________________________________________________________ CONTENTS 1) CELL WARS By Karen Miller 2) THE GREAT DYING By Patrick L. Barry 3) LOOKING FOR LIFE'S IMPRINT--LIGHT YEARS AWAY NASA/JPL release 4) STUDENTS CAN "SEARCH" FOR A HABITABLE PLANET ON NEW NASA WEB SITE NASA/ARC release 02-09AR 5) IS THERE LIFE BEYOND EARTH? By Andrew Chaikin 6) 30 BILLION EARTHS? NEW ESTIMATE OF EXOPLANETS IN OUR GALAXY By Robert Roy Britt 7) SOME MARS RESEARCHERS SEE LIFE IN PLANET'S DUNES By Leonard David 8) ARE WE THE GALAXY'S DUMBEST CIVILIZATION? By Seth Shostak 9) ANNIHILATING ANTHRAX By Tony Phillips 10) MARS ATLAS REVISITED: THE MGS MOC WIDE ANGLE MAP OF MARS NASA/JPL release 11) NEW ADDITIONS TO THE ASTROBIOLOGY INDEX By David J. Thomas 12) FOUR WEEKS ON GALILEO NASA/JPL release 13) MARS ODYSSEY MISSION STATUS NASA/JPL release 14) STARDUST STATUS REPORT NASA/JPL release _____________________________________________________________________ CELL WARS By Karen Miller From NASA Science News 23 January 2002 Immune cells vs. invaders: it's a war going on in every healthy human body. When the combatants travel to space, say NASA scientists, curious things happen. When you wake up, maybe you yawn, switch off your alarm clock, and listen for the perking of an automatic coffee maker--a normal morning routine on Earth. But if you were in orbit, the first thing you'd do is take a little roll of cotton, swish it around in your mouth, and then drop it in a tube filled with preservative. The cotton collects viruses, and the goal of that good-morning ritual is to help determine why astronaut saliva contains more viruses in space than it does on the ground. It's not a trivial question. Our bodies are chock-full of tiny invaders: bacteria, viruses, protozoans. Multitudes inhabit our gut, more slip in on the food we eat and through the air we breathe. Usually they're not a problem. Indeed, some are even helpful--and the ones that aren't are kept in check by our vigorous immune system, which marks and destroys pathogens before they get out of control. Without immune systems, humans would die. In space, our immune system functions differently. This complex system consists, essentially, of disease-fighting cells that can travel throughout the body. There are many kinds of immune cells; two of the most important are B-cells, which send out antibodies-- proteins that latch onto germs or other problem-causing invaders, flagging them as invaders to be destroyed, and T-cells, which are the soldiers of the system, physically attacking and destroying pathogens. In space, these cells don't work the way they do on the ground. T- cells, for example, don't multiply properly; there aren't as many of them as there should be. They can't move well. They don't signal each other as effectively. Overall, they seem less able to destroy invading germs. Here on Earth, doctors have learned that stress can suppress the immune system by causing the body to release hormones that affect the way T-cells behave. Likewise, the unique physical and psychological stresses of space flight (takeoff and landing, for example) might trigger immune-altering hormones. Another possibility is that something about space itself--weightlessness, perhaps, and not hormones at all--might affect immune cells directly. To help solve the mystery, researchers are using a NASA-developed "rotating bioreactor," which provides a reasonable analog of microgravity here on Earth. Neal Pellis, chief of the Biological Systems Office in the Johnson Space Center, explains: The core of the bioreactor is a soup-can size container that spins at the leisurely rate of 14 rpm. It allows cells to remain suspended for months at a time in continual free fall. Within their fluid environment, the tumbling cells fall toward Earth as fast as they can--just as they would in Earth orbit. Using the bioreactor, researchers can separate the immune system from its hormonal controls. Rather than looking at the human immune system as a whole, Pellis and his colleagues can examine the possible effects of low-gravity on individual immune cells. In the bioreactor, says Pellis, cells begin to change within the first 15 minutes. Indeed, one of the first alterations researchers observe could possibly trigger all the other effects: T-cells are somehow forced to remain round. It's an important change. On Earth, these cells can alter their shape. They're able to protrude portions of themselves--an ability that they use to move around, just like amoebas do. And they need to move in order to do their job: They travel to the sites of infections, where they attack germs. They move to the sites of tumors. They locomote in and out of immune system organs, such as the appendix and tonsils, where other T-cells share samples of invading pathogens. But it's not only the ability to move that's hampered by roundness. This simple change also makes it harder for cells to communicate. Round cells, explains Pellis, find it harder to touch each other. Their ability to interact is reduced. Imagine two balloons, he says. "If you put them side by side, and pressed them together, the surface area that's in contact can be quite large." But, he says, if you have two bowling balls, no matter how hard you press them together, only a tiny fraction of their surfaces will meet. Such cells have less ability to exchange the chemical signals that command them to go into action It's still unclear what these findings mean for the health of space travelers. Astronauts do show an increase in virus levels. For example, notes Duane Pierson, head of microbiology for the Johnson Space Center, when astronauts cough or sneeze, the droplets released contain 8 to 10 times more of the common Epstein-Barr virus (which causes infectious mononucleosis) than normal Earth sneezes. Although that's an indication of immune system suppression, the astronauts themselves have remained completely without symptoms. Nor is it yet clear exactly what keeps T-cells round. Without the usual effects of gravity, explains Pellis, other forces--perhaps intermolecular or submolecular forces, such as hydrogen bonding--must play a larger role, so that in microgravity, these other forces control the shape that the cell takes. "But exactly which forces are doing what to whom, where and how, to arrive at a spherical cell, I don't think anybody knows.” Finding out is important, and not only for astronauts. This research will also help people on Earth. T-cells protect us from all kinds of problems, says Pellis, but they don't always behave as we would like. "There are times when we don't want them to invade--transplants, for example. And there are cases when we want them to act vigorously, like in tumors." Understanding the way physical forces affect T-cells could eventually allow scientists to control them--"taming" them so that they help us, as they're meant to, in far more effective ways. Additional information on this article is available at http://science.nasa.gov/headlines/y2002/23jan_cellwars.htm?list52260. _____________________________________________________________________ THE GREAT DYING By Patrick L. Barry From NASA Science News 28 January 2002 250 million years ago something unknown wiped out most life on our planet. Now scientists are finding buried clues to the mystery inside tiny capsules of cosmic gas. It was almost the perfect crime. Some perpetrator--or perpetrators-- committed murder on a scale unequaled in the history of the world. They left few clues to their identity, and they buried all the evidence under layers and layers of earth. The case has gone unsolved for years--250 million years, that is. But now the pieces are starting to come together, thanks to a team of NASA-funded sleuths who have found the "fingerprints" of the villain, or at least of one of the accomplices. The terrible event had been lost in the amnesia of time for eons. It was only recently that paleontologists, like hikers stumbling upon an unmarked grave in the woods, noticed a startling pattern in the fossil record. Below a certain point in the accumulated layers of earth, the rock shows signs of an ancient world teeming with life. In more recent layers just above that point, signs of life all but vanish. Somehow, most of the life on Earth perished in a brief moment of geologic time roughly 250 million years ago. Scientists call it the Permian-Triassic extinction or "the Great Dying"--not to be confused with the better-known Cretaceous-Tertiary extinction that signaled the end of the dinosaurs 65 million years ago. Whatever happened during the Permian-Triassic period was much worse. No class of life was spared from the devastation. Trees, plants, lizards, proto- mammals, insects, fish, mollusks, and microbes--all were nearly wiped out. Roughly 9 in 10 marine species and 7 in 10 land species vanished. Life on our planet almost came to an end. Scientists have suggested many possible causes for the Great Dying: severe volcanism, a nearby supernova, environmental changes wrought by the formation of a super-continent, the devastating impact of a large asteroid--or some combination of these. Proving which theory is correct has been difficult. The trail has grown cold over the last quarter billion years; much of the evidence has been destroyed. "These rocks have been through a lot, geologically speaking, and a lot of times they don't preserve the (extinction) boundary very well," says Luann Becker, a geologist at the University of California, Santa Barbara. Indeed, there are few 250 million-year- old rocks left on Earth. Most have been recycled by our planet's tectonic activity. Undaunted, Becker led a NASA-funded science team to sites in Hungary, Japan and China where such rocks still exist and have been exposed. There they found telltale signs of a collision between our planet and an asteroid 6 to 12 km across--in other words, as big or bigger than Mt. Everest. Many paleontologists have been skeptical of the theory that an asteroid caused the extinction. Early studies of the fossil record suggested that the die-out happened gradually over millions of years- -not suddenly like an impact event. But as their methods for dating the disappearance of species has improved, estimates of its duration have shrunk from millions of years to between 8,000 and 100,000 years. That's a blink of the eye in geological terms. "I think paleontologists are now coming full circle and leading the way, saying that the extinction was extremely abrupt," Becker notes. "Life vanished quickly on the scale of geologic time, and it takes something catastrophic to do that." Such evidence is merely circumstantial--it doesn't actually prove anything. Becker's evidence, however, is more direct and persuasive. Deep inside Permian-Triassic rocks, Becker's team found soccer ball- shaped molecules called "fullerenes" (or "buckyballs") with traces of helium and argon gas trapped inside. The fullerenes held an unusual number of 3He and 36Ar atoms--isotopes that are more common in space than on Earth. Something, like a comet or an asteroid, must have brought the fullerenes to our planet. Becker's team had previously found such gas-bearing buckyballs in rock layers associated with two known impact events: the 65 million- year-old Cretaceous-Tertiary impact and the 1.8 billion-year-old Sudbury impact crater in Ontario, Canada. They also found fullerenes containing similar gases in some meteorites. Taken together, these clues make a compelling case that a space rock struck the Earth at the time of the Great Dying. But was an asteroid the killer, or merely an accomplice? Many scientists believe that life was already struggling when the putative space rock arrived. Our planet was in the throes of severe volcanism. In a region that is now called Siberia, 1.5 million cubic kilometers of lava flowed from an awesome fissure in the crust. (For comparison, Mt. St. Helens [in Washington State] unleashed about one cubic kilometer of lava in 1980.) Such an eruption would have scorched vast expanses of land, clouded the atmosphere with dust, and released climate-altering greenhouse gases. World geography was also changing then. Plate tectonics pushed the continents together to form the super-continent Pangea and the super- ocean Panthalassa. Weather patterns and ocean currents shifted, many coastlines and their shallow marine ecosystems vanished, sea levels dropped. "If life suddenly has all these different things happen to it," Becker says, "and then you slam it with a rock the size of Mt. Everest--boy! That's just really bad luck." Was the "crime" then merely an accident? Perhaps so; nevertheless, it's wise to identify the suspects--an ongoing process--before it happens again. Note: Becker's colleagues include Robert Poreda and Andrew Hunt from the University of Rochester, NY; Ted Bunch of the NASA Ames Research Center; and Michael Rampino of New York University and NASA's Goddard Institute of Space Sciences. NASA's Astrobiology and Cosmochemistry programs and the National Science Foundation provided funding for the research. Additional information on this article is available at http://science.nasa.gov/headlines/y2002/28jan_extinction.htm?list5226 0. _____________________________________________________________________ LOOKING FOR LIFE'S IMPRINT--LIGHT YEARS AWAY NASA/JPL release http://www.jpl.nasa.gov/stars_galaxies/features/light_imprint.html 28 January 2002 Are we alone in the universe? Short of receiving a convenient radio transmission from another civilization, how can we find out if a distant world harbors some form of life? The discovery of more than 70 planets outside our solar system within less than a decade has brought a new sense of immediacy to the search for life. Scientists believe our best bet might be to build instruments capable of detecting life's chemical signatures, called biosignatures, or biomarkers. Terrestrial Planet Finder, a mission managed by JPL for NASA's Origins program, will be among the first generation of instruments capable of searching for the atmospheric "life signs" of habitable, or even inhabited, planets. Terrestrial Planet Finder, scheduled for launch in 2014, will deploy revolutionary technologies to block the blinding glare of a star. By doing this, scientists will be able to detect planets as small as Earth, which are considered better prospects for life than the large planets detectable with current technology. The closest planetary systems are many light years away, but the faint light the planets emit, if separated into its component frequencies, can provide a wealth of information. By analyzing the colors of infrared radiation detected by Terrestrial Planet Finder, astronomers can search for atmospheric gases such as carbon dioxide, water vapor and ozone. The best candidates for closer study would be located in the habitable zone, the region around the system's star where we can expect to find liquid water, which is considered a prerequisite for life. If the planet is too hot, the water evaporates. If the planet is too cold, the water freezes. Earth is inside the habitable zone for our star, the Sun; the zone starts beyond Venus and ends before Mars. Among the most reliable biomarkers we might find is oxygen--a byproduct of photosynthesis on Earth. Oxygen molecules don't linger in the atmosphere, but combine with other molecular types in a process known as oxidation. An even more valuable biomarker is ozone, a form of oxygen that's easier to detect by analyzing the wavelengths of light. So, a planet with an atmosphere rich in oxygen or ozone implies the presence of a source to keep it replenished--in other words, life, right? Not so fast, says James F. Kasting of Pennsylvania State University, a member of the Terrestrial Planet Finder science working group. "We know of non-biological processes that can also result in an oxygen- rich atmosphere," Kasting said. "The runaway greenhouse effect on Venus is one example. A frozen, Mars-like planet big enough to hold its oxygen would be another." Still, the presence of ozone would at least suggest we're "getting warm" in the search for life. What additional clues could we look for? The most persuasive indicator of life, Kasting says, would be the simultaneous presence of oxygen or ozone, along with another chemical such as methane or nitrous oxide. These gases are more abundant than we might expect in Earth's atmosphere. They are present because they, too, are produced by organisms. Methane comes from a type of bacteria that lives in soils without oxygen, such as rice paddies, and in the intestines of cows and sheep. Nitrous oxide comes from a type of bacteria in the ocean and in soils without oxygen. James Lovelock, a British scientist who has written numerous books on the "Gaia Hypothesis"--the theory that life controls atmospheric composition and climate--suggested more than 30 years ago that the simultaneous presence of oxygen and a reduced gas like nitrous oxide or methane would be strong evidence for life. This advice is still considered good today, Kasting says. In any case, the large-scale chemical clues won't tell us about the complexity of the discovered life; it could be either algae or a developed civilization. It's possible that planets without oxygen could sustain life as well. Photosynthesis might conceivably occur with another element, such as sulfur, playing the role of oxygen. In the search for life, scientists acknowledge, we must control our assumptions of just what it means to be living. Related links Planet Quest: the Search for Another Earth http://planetquest.jpl.nasa.gov Terrestrial Planet Finder http://planetquest/TPF/tpf_index.html An additional article on this subject is available at http://www.spacedaily.com/news/extrasolar-02b.html. _____________________________________________________________________ STUDENTS CAN "SEARCH" FOR A HABITABLE PLANET ON NEW NASA WEB SITE NASA/ARC release 02-09AR 29 January 2002 Searching for a fictional planet on which people could live is one of the student activities available on a new NASA web site that will open for business on February 1 at http://astroventure.arc.nasa.gov. "Astro ferret," a cartoon character, will guide students through a series of role-playing steps on the multi-media, interactive web site. Young people using the "Astro-venture" web site can observe the effects of changes to the Earth and draw conclusions about what is needed for survival. Participants can "feel" that they are part of an Internet world by7 receiving information seamlessly, through use of graphics, audio, video and audio transcriptions. "Students in grades 5-8 are transported to the future where they role-play NASA occupations and use scientific inquiry, as they search for and eventually build a planet with the necessary characteristics for human habitation," said Christina O'Guinn of the educational technology team at NASA Ames Research Center, in California's Silicon Valley. "Supporting activities include Internet webcasts with real NASA scientists, online collaborations, classroom lessons, a student publishing area and occupation-related fact sheets and trading cards." Webcasts enable students to watch live video, listen to audio and interact in real-time on the Internet with experts. The webcasts' URL is http://quest.nasa.gov/astrobiology/astroventure/2002/index.html. Two one-hour Astro-venture webcasts will take place in April. The first, "Habitable Planets," will be on April 2 at 10:00 AM PST. The second, "Doppler Shift," will take place on April 9 at 10:00 AM PDT. "Our goal is to inspire students to pursue science, math and technology careers by engaging them in an extremely compelling topic, astrobiology, in a way that is very relevant to them, focusing on Earth and human survival," said Donald James, education director at NASA Ames. Astrobiology is the study of the origin, evolution, distribution and destiny of life in the universe. "Research shows that it is crucial to capture students' interest in science before they reach high school," he said. O'Guinn will describe the "Astro-venture" web site to as many as 150 teachers who will be attending a "Space in the Classroom" conference at the Golden State Museum in Sacramento, CA. The conference, for K- 12 educators, is sponsored by the California Space Authority and will be hosted by the Space Foundation of Colorado Springs, Colo. More information about the conference can be found at http://www.spacefoundation.org/sitc. The astronomy section of NASA's new web site zeros in on our solar system's astronomical characteristics that make it livable to human beings. "Students test cause-and-effect relationships to discover the characteristics that allow Earth to remain habitable. Students also will explore hands-on, inquiry-based lessons on states of matter and systems and then complete a mission in which they simulate the process scientists might use to find a planet that would be habitable to humans," said O'Guinn. Students can participate in the NASA-sponsored Astro-venture Internet events without pre-registering. There is no charge. The Astro- venture lessons meet national education standards and provide a purpose for understanding concepts such as states of matter. "Since we need liquid water to survive, we need to understand how liquid water is different from solid and gas and what conditions allow for water to be a liquid," O'Guinn explained. The web site also highlights NASA careers and astrobiology research in astronomy, geology, biology and atmospheric sciences. According to web team members, they are developing the web site to meet educational standards, research-based instructional methods and the constraints of today's classrooms. The team includes instructional designers, graphic artists, multimedia programmers and web developers who work with NASA scientists, including some astrobiologists and their support personnel from the NASA Astrobiology Institute, which is headquartered, at NASA Ames. Astrobiologists at NASA Ames are studying the organic chemistry of space, the formation of planetary systems, and the early history of the Earth, one NASA astrobiologist explained. These scientists investigate the origin of life and explore the most extreme environments that support life, from boiling hot springs to cold Antarctic rocks. Astrobiologists analyze Martian meteorites for possible fossil evidence of life and carry out experiments in evolutionary biology using space shuttle flights. "NASA Ames also is beginning a collaboration with California State University, Hayward, educational technology graduate students who are rapid-prototyping other modules and curriculum," O'Guinn said. Contacts: John Bluck NASA Ames Research Center, Moffett Field, CA Phone: 650-604-5026 or 604-9000 E-mail: jbluck@mail.arc.nasa.gov Julie Howell Space Foundation, Colorado Springs, CO Phone: 719-576-8000, extension 103 E-mail: julie@spacefoundation.org _____________________________________________________________________ IS THERE LIFE BEYOND EARTH? By Andrew Chaikin From Space.com 29 January 2002 ...Stare into a starry night sky and ask yourself if someone, or something, might be staring back. Just the thought is enough to make the hair on the back of your neck stand up. But even now, after centuries of wondering, and decades of actively looking, humans still don’t know the answer. But that may be because they haven’t been asking the right questions. We Earthlings know only one type of life, in only one place. The very idea of looking for life elsewhere confronts us with a series of questions that are maddeningly undefined. Where should we look? Can we even be sure what we’re looking for? Or how to find it? These are the kinds of questions Ken Nealson struggles with. A geo- biologist at the University of Southern California, Nealson is heavily involved in devising strategies for searching for extraterrestrial life. And his number one goal is to free himself and his colleagues from the confines of their own preconceptions about life. "It seems to me the worst people to look for life are biologists," Nealson, also a senior scientist at the NASA/Caltech Jet Propulsion Laboratory, says. "Because they’re so darned sure of what life is that if it happened to be different, they’d miss it." Nealson admits this point of view isn’t very popular with his colleagues. "Oh, they love me," he laughs. "At least I'm a biologist saying it, so they can’t just claim I'm some mad physicist who’s trying to take their funding away." Get the full story at http://www.space.com/news/cosmic_life_020129- 1.html. _____________________________________________________________________ 30 BILLION EARTHS? NEW ESTIMATE OF EXOPLANETS IN OUR GALAXY By Robert Roy Britt From Space.com 29 January 2002 Chances are you haven't spent a whole lot of time wondering how many Jupiter-like planets exist in our galaxy. But Charley Lineweaver has, because it bears on a more important question. How many potentially habitable planets are there? New calculations by Lineweaver and Daniel Grether, both of the University of New South Wales in Australia, provide an encouraging answer to this question. The researchers expect a flood of Jupiters will be found, perhaps 50 percent more than currently expected. Each such discovery would be significant in the hunt for planets that could harbor life. Why? Because much of the evolution of our own solar system, including the formation of Earth, was orchestrated or affected by Jupiter, the largest planet with by far the bulk of the solar system's mass, excepting the Sun, of course. ...When Jupiter developed, it simply bullied other objects into position or out of existence. Then the mighty gas giant became Earth's protector. Though the fledgling Earth was pummeled by asteroids and comets, making it difficult for life to take hold, it could have been much worse. Jupiter shielded Earth from an even heavier bombardment of debris that made its way from the outskirts of the new system toward its central star. Get the full story at http://www.space.com/scienceastronomy/astronomy/jupiter_typical_02012 8.html. _____________________________________________________________________ SOME MARS RESEARCHERS SEE LIFE IN PLANET'S DUNES By Leonard David From Space.com 30 January 2002 A Hungarian research team claims that Martian organisms dot certain areas of the Red Planet. Calling the intriguing blemishes "dark dune spots", the scientists argue that these changing features are "probable Martian surface organisms." Their evidence is based on studies of imagery snapped by NASA's Mars Global Surveyor (MGS), a spacecraft now orbiting that planet. However, this is at odds with the published conclusions of the MGS team, and at least one leading Mars researcher and astrobiology expert deems the life-form assertion "premature". This is also not the first time that images of Martian surface features from MGS have sparked the life debate. Get the full story at http://www.space.com/scienceastronomy/solarsystem/mars_blotches_02013 0.html. _____________________________________________________________________ ARE WE THE GALAXY'S DUMBEST CIVILIZATION? By Seth Shostak From Space.com 31 January 2002 What does it mean to be intelligent? I get this question a lot, given the fact that "intelligence" is the last word of the SETI acronym. "Is there intelligence on Earth?" wags will ask (and by so doing, make their query relevant). What defines a species as intelligent, and how do SETI researchers decide? SETI folk are mostly interested in alien intelligence, not the brainpower of the local school kids. But investigating terrestrial IQs may help us estimate how often sentient beings evolve elsewhere. To test human intelligence is straightforward, if controversial. But how can we assess the brainpower of other critters? One approach taken by biologists is to compute an "encephalization quotient," which is really no more than a measure of how weighty the brain is for an animal of a given body size. Of course, bigger bodies usually mean bigger brains (compare--at least in your mind, if not the kitchen--the brain of a rhino to that of a mouse). But sheer size isn’t the whole story. Animals of any given mass have a variety of brain weights. Those with the heftier cerebrums are observed to have more sophisticated behavior, and are ranked as smarter. Humans, it will not surprise you to learn, have the largest brains for their body mass, roughly twice that of their nearest intellectual competitors, the chimps. That factor-of-two difference determines who runs the planet. This is all interesting for studying the evolution of sentience, but in practice SETI has a far simpler definition of what it means to be intelligent: you’re "intelligent" if you can build a powerful laser or a thumping radio transmitter. After all, that’s what we demand if our SETI experiments are going to find something. In other words, the "intelligence" in SETI really means technical sophistication. By that very practical, operational definition, humans have been intelligent for less than a century. Get the full story at http://www.space.com/searchforlife/seti_dumbest_020131.html. _____________________________________________________________________ ANNIHILATING ANTHRAX By Tony Phillips From NASA Science News 1 February 2002 NASA- and industry-sponsored research aimed at growing plants in space has led to a device that attacks and destroys airborne pathogens--like anthrax. Unseen and odorless, a cloud of Anthrax spores wafts through an office. People inside are talking, laughing... breathing. They have no idea something is in the air. One yawn, one gasp, one happy guffaw could be deadly. That's how bioterrorism works. But this office has a defense. Bolted to the ceiling is a curious flat box. It's made of metal, about the size of a table-top, and it's humming softly--the sound of fans drawing airborne spores toward it and away from the people. The breeze is gentle but insistent. Eight cubic feet of air per minute flow into the box. What lies inside is bad news for anthrax. Swirling air forces spores through a bewildering maze of thin tubes bristling with hydroxyl (OH-) ions that attack and destroy pathogens. Some spores are buffeted against the OH--lined walls of the labyrinth. Others are caught in windy eddies where they linger, exposed to high-energy (254 nm) ultraviolet photons. Every second, one hundred billion such photons bathe the chamber--and just one is enough to destroy a spore. "Spores that pass through the box aren't filtered, they're fried," says John Hayman, whose company, KES Science & Technology, Inc., builds and sells the device called AiroCide TiO2. "That's appealing," he notes, "for people who don't want to change an anthrax-laden air filter." Tests show that as many as 93% of Anthrax spores that enter AiroCide TiO2 are destroyed. Survivors circulate out of the chamber where they are likely to be sucked back in again for another pass. This extraordinary anthrax killer is a result of NASA- and industry- sponsored research aimed at building better greenhouses in space. "Greenhouses may seem to have little to do with the war against terror," says Mark Nall, the director of NASA's Space Product Development (SPD) program. "But this shows how space research, along with its direct benefits, also helps people on Earth in indirect and unexpected ways." Hayman explains, "[Space faring] astronauts will eventually need to grow some of their own food in greenhouses. But there's a problem: the leaves of growing plants release ethylene (C2H4)--a gas that causes fruits and vegetables to mature." In the close quarters of a spacecraft (or inside an enclosed plant growth chamber), ethylene would build up and ripen greenhouse plants prematurely. Space greenhouses needed a new technology to remove that ethylene. Marc Anderson, a professor and chemist at the University of Wisconsin-Madison, led the team that made a crucial discovery in the mid-1990's. They found that ultra-thin layers of titanium dioxide (TiO2) exposed to ultraviolet light would efficiently convert ethylene into carbon dioxide (CO2) and water (H2O)--substances that are good for plants. Titanium dioxide itself is a harmless, non-toxic coloring agent used in many consumer products. It is a catalyst for the ethylene-destroying reaction; no TiO2 is consumed. TiO2-based ethylene removers have since flown to space inside a pair of plant growth chambers: Astroculture™ on board NASA's space shuttle and Advanced Astroculture™ on the International Space Station (ISS). Both were designed and built by the Wisconsin Center for Space Automation and Robotics (WCSAR) in collaboration with Marc Anderson. (WCSAR is a NASA Commercial Space Center at the University of Wisconsin--one of 17 such centers around the country sponsored by NASA's Space Product Development program to encourage the commercialization of space by industry.) The technology worked so well that the University of Wisconsin then joined forces with KES Science and Technology, Inc., to develop an ethylene scrubber for Earth. The device, called Bio-KES, works wonders in supermarkets where ethylene in the air of produce aisles reduces the shelf life of vegetables. Bio-KES was nominated as Discover Magazine's Product of the Year in 1998, and it's since been shipped across the globe for use by grocers and florists. Moreover, Bio-KES is the parent of AiroCide TiO2. "It was a serendipitous discovery," recalls Hayman. Tests showed that Bio-KES not only removed ethylene, but also killed airborne dust mites. Marc Anderson quickly realized why. When ultraviolet (UV) photons strike something coated by TiO2--like the tubes inside Bio- KES--positive and negative charges appear on its surface. Those charges tear apart nearby water molecules. The OH- ion, a by-product of the reaction, disrupts organic molecules. It's deadly to dust mites, anthrax and many other pathogens. Technicians modified Bio- KES--adding higher-power UV lamps, for example, to give it "an extra kick," says Hayman--and AiroCide TiO2 was born. Dean Tompkins, a colleague of Anderson's at the University of Wisconsin, is in charge of testing AiroCide TiO2. "We don't use real anthrax," he notes. "That would be too dangerous. Instead, we experiment with one of its non-virulent cousins, Bacillus thurengiensis." During a typical experiment, Tompkins propels a cloud of approximately 1000 spores through the AiroCide chamber. Only 100 or so emerge intact. Spores that enter AiroCide TiO2 spend at least 5 to 10 seconds in transit through the device. "That's important," adds Hayman, "because pathogens that remain inside longer are more likely to die." To slow the spores, TiO2-coated tubes within the unit are randomly arranged--there's no direct path through the machine. When air moves across the jumbled tubes, the flow becomes turbulent--forcing spores to linger where they can be attacked by OH- and illuminated by germ- killing ultraviolet light. Such powerful tools against bio-terror indeed seem a far cry from star-trekking greenhouses, but that's how many discoveries are made. You never know what new invention might emerge--like AiroCide TiO2--or what might be annihilated in the process--like anthrax! More information on this article is available at http://science.nasa.gov/headlines/y2002/01feb_anthrax.htm?list52260. _____________________________________________________________________ MARS ATLAS REVISITED: THE MGS MOC WIDE ANGLE MAP OF MARS NASA/JPL release http://www.msss.com/mars_images/moc/moc_atlas/index.html 1 February 2002 In 1979, NASA published ATLAS OF MARS: THE 1:5,000,000 MAP SERIES, edited by R. M. Batson, P. M. Bridges, and J. L. Inge, of the U.S. Geological Survey in Flagstaff, Arizona. This was a compendium of airbrushed shaded relief maps, controlled photomosaics, and in a few cases albedo (shading) maps, mostly assembled from Mariner 9 survey images, with some gaps filled by Viking orbiter images. The planet was divided into thirty "quadrangles" or areas, each with an "Mars Chart" or "MC" number (MC-1 through MC-30). The equatorial region was portrayed in the Mercator projection, with Lambert Conformal Conic for the mid-latitudes and Polar Stereographic for the poles. Although digital products such as the Mars Digital Image Mosaic (MDIM) and various Mars Global Surveyor (MGS) Mars Orbiter Laser Altimeter (MOLA) maps have partially supplanted the ATLAS, it remains a standard desktop reference today. In 1999, the Mars Orbiter Camera (MOC) aboard the MGS orbiter acquired a global stereo image dataset using its red-filter Wide Angle Camera. We have recently completed a 256 pixel/degree (about 230 meters/pixel) mosaic of these images using software developed at Malin Space Science Systems (MSSS). To access both partial and full- resolution mosaics in Planetary Data System format, go to http://www.msss.com/mgcwg/mgm/. The image above is a reproduction of the new MGS MOC Mars Digital Map. By clicking on the various sections (quadrangles) of the map, one can access the atlas at two resolutions: first a browse image at about 6 km/pixel, and by clicking on that browse image, at a resolution of about 1 kilometer per pixel (~0.62 miles per pixel). Each quadrangle is independently contrast-enhanced and labeled with a 5-degree grid. This is the first of several cartographic products that MSSS expects to release this year. The index map can be viewed at full resolution at http://www.msss.com/mgcwg/mgm/mc21.jpg. Malin Space Science Systems 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. _____________________________________________________________________ NEW ADDITIONS TO THE ASTROBIOLOGY INDEX By David J. Thomas http://www.lyon.edu/webdata/users/dthomas/astrobiology/astrobiology.h tml 4 February 2002 Articles about astrobiology, exobiology and terraformation http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_article s1.html R. R. Britt, 2002. 30 billion Earths? New estimate of exoplanets in our galaxy. Space.com. A. Chaikin, 2002. Is there life beyond Earth? Space.com. L. David, 2002. Some Mars researchers see life in planet's dunes. Space.com. SpaceDaily, 2002. Looking for life's imprint--light years away. SpaceDaily. Articles about human space exploration and the microgravity environment http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_article s3.html K. Miller, 2002. Cell wars. NASA Science News. T. Phillips, 2002. Annihilating anthrax. NASA Science News. Articles about the search for extraterrestrial intelligence (SETI) http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_article s4.html S. Shostak, 2002. Are we the galaxy's dumbest civilization? Space.com. Articles about evolutionary biology and chemistry http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_article s5.html P. L. Barry, 2002. The great dying. NASA Science News. _____________________________________________________________________ FOUR WEEKS ON GALILEO NASA/JPL release 28 January - 24 February 2002 The long cruise period between encounters is now under way. In fact, this is the longest period between encounters that Galileo has spent since entering orbit around Jupiter in December 1995. Between our January 17 flyby of Io and the November 5 flyby of Amalthea, 292 days will pass. This long, looping trajectory will also take us the farthest from Jupiter we have been since entering orbit. On June 13 we will reach a distance of 348 Jupiter radii from the planet, which is nearly 25 million kilometers or 15.5 million miles. At that distance, light from the giant planet takes nearly a minute and a half to reach the spacecraft! On the same day the signal from Galileo takes 49.8 minutes to travel all the way to Earth. Tuesday morning, January 29, the spacecraft executes a small 2-degree turn in place to keep the communications antenna pointed towards Earth. Friday night, February 1, the Near Infrared Mapping Spectrometer (NIMS) performs the final planned remote sensing observation of the mission. This observation is a calibration to determine the response of the instrument to a known input signal. By periodically performing these calibrations throughout the mission, scientists are able to track how the performance of the instrument changes with time. This allows them to translate the instrument measurements into absolute physical quantities. On Monday night, February 11, routine maintenance of the spacecraft propulsion system is performed. On Wednesday, February 13, routine maintenance of the tape recorder is performed. On Friday night, February 22, the path of Jupiter and the spacecraft in Earth's sky takes it near our own Moon as seen by the tracking station near Madrid, Spain. Though the Moon does not actually block the spacecraft, reflected the antenna can see thermal radiation from the surface of this very close body, and this can interfere with the signal from the spacecraft. Data return from Galileo this month consists of playback of the recorded data that we were able to acquire during the Io flyby. These data include pictures of Europa and Amalthea (though not, unfortunately, of Io), and of Jupiter's atmosphere. Also included is a set of global maps of Jupiter's clouds by NIMS. While the playback continues, the Magnetometer, the Dust Detector, and the Extreme Ultraviolet Spectrometer continue collecting and periodically transmitting real-time data about the local environment of the spacecraft and about the interplanetary hydrogen distribution. With the long gap between highlights, these reports are shifting to a monthly publishing schedule. Weekly reports will resume in October as we approach Amalthea and the activity level for the spacecraft picks up. For more information on the Galileo spacecraft and its mission to Jupiter, please visit the Galileo home page at one of the following URL's: http://galileo.jpl.nasa.gov http://www.jpl.nasa.gov/galileo _____________________________________________________________________ MARS ODYSSEY MISSION STATUS NASA/JPL release 30 January 2002 NASA's Mars Odyssey spacecraft is now in its mapping orbit after completing two maneuvers this week to fine-tune its nearly circular orbit and prepare it for the start of the science mission. At 12:14 PM Pacific Time today, Odyssey fired its thrusters for 25 seconds and decreased the velocity of the spacecraft by less than 2 meters per second (less than 4 miles per hour). On Monday, January 28, Odyssey fired its thrusters for 15 seconds, increasing its speed by just over 1 meter per second (about 2.5 miles per hour). "These small orbit trim maneuvers complement the larger maneuvers we executed two weeks ago and tweak the orbit to get just the right altitude and ground track coverage that we desire. The net effect is that we move the periapsis point, the point nearest the planet, directly over the south pole and keep it there," said Bob Mase, Odyssey's lead navigator at NASA's Jet Propulsion Laboratory, Pasadena, CA. "We are now in our final mapping orbit and we don't expect to perform any additional maneuvers to change the orbit." Engineers are continuing to check out the spacecraft systems and science instruments in preparation for the science mapping mission that will begin in February. Two of the science instruments, both neutron spectrometers that are part of the gamma ray spectrometer suite, are currently operating and collecting science data about the composition of the Mars surface. JPL manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, DC. Principal investigators at Arizona State University in Tempe, the University of Arizona in Tucson, and NASA's Johnson Space Center, Houston, Texas, operate the science instruments. Additional science investigators are located at the Russian Space Research Institute and Los Alamos National Laboratories, New Mexico. Lockheed Martin Astronautics, Denver, CO, is the prime contractor for the project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena. NASA's Langley Research Center in Hampton, VA, has provided aerobraking support to JPL's navigation team during mission operations. _____________________________________________________________________ STARDUST STATUS REPORT NASA/JPL release 1 February 2002 There were two Deep Space Network tracking passes in the past week and all subsystems are normal. Stardust is currently 2.66 AU (247 million miles or 397 million miles) from the Sun. Telemetry and navigation tracking verified that Deep Space Maneuver #2 was performed flawlessly. The Stardust Outreach team presented its Education and Public Opportunity Wild 2 Encounter Plan to the JPL Solar System Leadership Council. This plan included interactions with the armada of other missions having critical events during late 2003 and early 2004 and included planned events during the spacecraft encounter. The Outreach team and the Stardust Principal Investigator, Don Brownlee, conducted a virtual training session on comets and astrobiology to the 17 Solar System Educator's participating in the program. For more information on the Stardust mission--the first ever comet sample return mission--please visit the Stardust home page at http://stardust.jpl.nasa.gov. _____________________________________________________________________ End Marsbugs, Volume 9, Number 5.