MARSBUGS: The Electronic Astrobiology Newsletter Volume 9, Number 22, 17 June 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) STUDY OF FOSSILS FOUND IN ARCTIC SHOWS PLANTS MORE DEVELOPED AT EARLIER TIME By David Williamson 2) HIGH-PRESSURE LIVING By Astrobiology Magazine staff 3) WORLDS OF LIFE BEYOND EARTH By Pat Sheil 4) FOSSILS POINT TO ASTEROID CAUSING DINOSAURS' DEMISE By James Randerson 5) WHITHER EUROPA? RESEARCHERS REGROUP TO MAKE JUPITER'S MOON NASA'S PRIORITY By Leonard David 6) SALT OF THE EARLY EARTH By Leslie Mullen 7) ASTRONAUT FINGERS By Tony Phillips and Steve Price 8) LONG-DURATION ASTRONAUTS NEED PEOPLE SKILLS By William Harwood 9) EXTRATERRESTRIAL JUPITER From NASA Science News 10) WHAT TO SAY WHEN ET FINALLY CALLS By Douglas Vakoch 11) NEW ADDITIONS TO THE ASTROBIOLOGY INDEX By David J. Thomas 12) CASSINI SIGNIFICANT EVENTS NASA/JPL release 13) INTERNATIONAL SPACE STATION EXPEDITION FOUR SCIENCE OPERATIONS STATUS REPORT NASA/MSFC release 02-148 14) MARS ODYSSEY THEMIS IMAGES NASA/JPL/ASU release 15) STARDUST STATUS REPORT NASA/JPL release _____________________________________________________________________ STUDY OF FOSSILS FOUND IN ARCTIC SHOWS PLANTS MORE DEVELOPED AT EARLIER TIME By David Williamson From UNC News Services 7 June 2002 Along with Canadian colleagues, a University of North Carolina at Chapel Hill scientist has discovered fossils of plants dating back some 420 million years. The discovery, made on Bathurst Island in the Northwest Territories about 800 miles from the North Pole, shows vascular plants were more complex at that time than paleontologists previously believed and is significant for that reason, the UNC researcher said. "These are not the earliest vascular plants ever found, but they are the earliest ever found of this size, complexity and degree of diversification," said Dr. Patricia G. Gensel, professor of biology at UNC. "They look something like medium-sized grasses, except that they branch." The discovery adds to the sparse record of early land plants known from North America, Gensel said. Previously, most information on ancient plants has been based on fossils from Wales, Venezuela and China. A report about the findings appears in the June issue of the American Journal of Botany. Besides Gensel, authors are UNC graduate student, Michele E. Kotyk, Dr. James F. Basinger, professor of geology at the University of Saskatchewan, and Dr. Tim A. de Freitas, a Calgary, Canada geologist working for Nexen Inc. Bits and pieces of the earliest known land plants date back almost 500 million years to the Ordovician Period, and their fragmentary remains indicate the plants were related to liverworts that exist today, Gensel said. The earliest vascular plants--ones with water- conducting tissues--so far are known to date back about 425 million years. Sparsely branched, they were about an eighth of an inch tall and grew a few reproductive bodies known as sporangia on their branches. By contrast, the new plants, which lived only a few million years later, would have stood four or more inches tall, bore many branches with dense rows of sporangia and probably grew in clusters, she said. They more closely resembled much younger early Devonian plants from about 390 million years ago than any other Silurian forms. "We found these previously unknown plants in rocky sediments we collected and brought back first by helicopter and then airplane from Bathurst in 1994," the biologist said. "Because of permafrost, digging is impossible, and we picked them up and chipped them out from exposed slopes on the almost completely barren island. Although we worked in July, some days it stayed near freezing all day long. When these plants were alive this land lay near the equator." The team dated specimens by finding them in the same layers as several tiny invertebrate fossilized animals such as graptolites, which under the microscope resemble band saw blades, and conodonts, which resemble miniature jaws and teeth and represent the mouthparts of primitive vertebrates. Such animal remains are excellent index fossils--fossils that indicate time. "We conclude that the Bathurst Island flora presents the best evidence to date of substantial diversity of form, complexity and stature of vascular plants in this period," Gensel said. In 1996, she and colleagues in Virginia and Northern Ireland reported finding fossils of scorpions, millipedes and related arthropods dating back almost 400 million years. Those creatures, which predated dinosaurs and other reptiles by some 50 million to 100 million years, were the largest animals ever found on land up to that time in North America. "Much of science is devoted to understanding and curing diseases, and that’s as it should be," Gensel said. "However, we also need to understand where living things have come from, which we can do by studying fossils. That gives us a better perspective on why the Earth and life are as they are today." Contacts: David Williamson Phone: 919-962-8596 Dr. Patricia Gensel Phone: 919-962-6937 E-mail: pgensel@bio.unc.edu An additional article on this subject is available at http://www.spacedaily.com/news/life-02ze.html. The original article in the American Journal of Botany (volume 89, pages 1004-1013) is available at http://www.amjbot.org/cgi/content/abstract/89/6/1004. _____________________________________________________________________ HIGH-PRESSURE LIVING By Astrobiology Magazine staff From Astrobiology Magazine, NASA Astrobiology Institute 11 June 2002 Descend 30 miles below ground or 100 miles beneath the ocean, and living conditions get extreme. In fact, even at room temperature, the pressures at such depths would compact a single bacterial cell and squeeze any exterior water to solid ice. Because of these hostile conditions, most researchers have concluded that only some exotic forms of life might survive at such depths and high pressures- -about 16 thousand times sea level pressures. But a recent study published in Science magazine highlights what might reveal a large and subterranean biomass, even for common surface bacteria. These findings suggest looking for life deep underneath planetary bodies like the surface of Mars or Europa, where a habitable zone of high- pressure survivors might pool. At the Geophysical Laboratory of the Carnegie Institution of Washington, the scientific team headed by Dr. Anurag Sharma, a geophysicist, and James Scott, a microbiologist, tested such biological limits for high-pressure life. The tools they chose to probe some common bacteria combined their expertise in both physics and biology. They put these bacterial cultures in a vice-like grip, exerting pressure equivalent to plumbing the depths of the Earth. Under pressure Using a vice-like, diamond anvil traditionally found in high-pressure physics and geology laboratories, the team clamped down on two particular bacterial species--E. coli, a bacterium commonly found in the human gut, and the metal-reducing bacteria called Shewanella oneidensis. Shewanella is an important agent in the weathering of rocks, since the organisms can essentially respire "on dust" by reducing metal components to derive their energy. As an alternative control, E. coli was studied as one of the most common and well- described microbes. By most measures, more scientific knowledge has been accumulated on the E. coli organism, (its biochemistry, genetics and metabolism) than any other single species on Earth. Even on Earth, the question of a subterranean world turns out to be far from academic. Nearly half of the Earth's surface is considered to be deep sea (or 75 percent of the total ocean water, which covers more than 70 percent of the Earth's surface). Below 10 kilometers (6 miles), such deep water is often considered a biological wasteland because typical enzyme reactions begin to fail under extreme pressure. But while the exact estimates for subsurface biomass are difficult to gauge, by some accounts life on the surface is indeed the rarer, and not the more common, terrestrial biology at work. Sharma indicated that subsurface biomass is vast, with "estimates varying from 30 to more than 90 percent of the Earth surface diversity. This is only a speculative guess, since one has to consider much more restricted energy and environmental controls." Living outside ordinary pressure limits? According to Dr. Sharma, one feature of their approach was its holistic look at biological prerequisites for survival under extreme conditions. In previous work, "pressure limits were considered based on the limits to enzyme activity and cell membrane viability defined by biophysics studies. However, such studies were never done on whole organisms, until our study, which shows that pressure is not a limiting factor in the viability of life." But in the high-pressure laboratory, Sharma and Scott first tried to peg the room temperature survival of their bacterial cultures. Their first tests included staining both kinds of bacteria (which will highlight only those cells having an active metabolism and thus able to uptake a colored dye). A second test traced the biochemistry of how those surviving organisms might get their energy source. These studies showed survival but not necessarily reproduction or growth at high pressures. As a measure of the organisms' livelihood and resilience, the team plans further studies that will try to determine bacterial growth and replication rates. Even in the absence of oxygen such resilient bacteria can shift their metabolism to radically different pathways. In the case of the E. coli and Shewanella particularly, the bacteria drive their metabolism towards an energy-conserving respiration. Such remarkable dormancy hinges on the presence of a chemical called formate. Formate is the simplest organic acid. For the Carnegie scientists, formate metabolism also proved valuable as a traceable indicator that indeed the bacteria remained viable at the highest pressures yet studied on whole cells. Planetary challenges for plumbing the depths for life One high priority to study next is whether the high-pressure organisms develop a stable population by selection or adaptation. According to Scott, "One of the fundamental questions that needs to be asked now is whether the response exhibited by the bacteria is due to adaptation or selection. Our results raise important questions about the impact of pressure on the evolution of life". The answer to how such bacteria first got this survival trait will likely determine if a unique habitable zone can be found outside the laboratory on Earth or elsewhere in the solar system, and also whether such bacterial traits are common or appear only among their more exotic counterparts, the so-called extremophiles. In the simplest view of evolution, natural selection relies on survival of the fittest, where some percentage of the initial bacterial culture must have the capability to remain robust even at high pressure. But adaptation would likely rely on a more dynamic change within the population as a whole, where a different kind of survival pathway developed over generations to adjust to the inhospitable pressure. How such pressures stack up on other planetary bodies remains unknown. Results from the Galileo spacecraft showed that Europa almost definitely has a layer of ice between 60-120 miles (100 and 200 km) thick, but at such depths, most density probes have been unable to differentiate a liquid or solid. Other than the Earth, Europa is currently considered the most likely (and only) candidate in the solar system for finding any liquid water (as much as 50 km or 30 miles deep). Of the 61 moons in the solar system only four others (Io, Ganymede, Titan and Triton) are known to have atmospheres. Probing subsurface bacteria is a frontier that spans both biology and physics. The subsurface of a planetary body for instance, would likely still need a way to recycle or refresh its nutrient supply to the surface atmosphere and back. According to Sharma, "Eventually the metabolic components have to be recycled otherwise the whole system will eventually stall. Hence there needs to be at least some interaction with the atmosphere." In the wild, some of the deepest terrestrial samples were collected from Antarctica, underneath Lake Vostok, where viable organisms were recovered from a depth of two and half miles (~4 km) and at below freezing (14°F) or -10°C temperatures. One school of thought first proposed by Thomas Gold of Cornell indicated that the frequent coexistence of helium and petroleum in deep drilling pointed to a viable ecosystem many miles below the Earth's surface. According to Gold, the concentration of such helium is a possible biological tracer or signature of subterranean ecosystems. "Soon the only thing that should limit our investigation of the survivability of life on Earth and beyond is our imagination," concludes Scott. What's next? For the Carnegie science team, the challenges and opportunities of using a diamond anvil cell, or DAC, as a kind of petri dish are only beginning to be explored actively. As Sharma notes, many experiments are planned or already in the works. For instance, "although there is no evidence for cell division at these extreme conditions, the cells have however, shown changes in shape, increased size, deformations etc.," said Sharma. "We are in the middle of completing experiments to determine whether there is any cell division ('growth') after the system has undergone decompression, which will answer quite a lot of important questions on implications of this study." "I think another challenge will be to be able to take advantage of molecular biological tools and tags in the DAC. Labeling cells with RNA probes to test for protein synthesis and cell replication might pin down the growth question." E. coli particularly contains over 1,000 known soluble enzymes, many of which can be traced in the complex chains of its life cycle. "Also," notes Sharma, "the challenge of doing analyses with the cells after coming out of the DAC is still an important challenge, as there are many analyses that can not be done inside the diamond cell. How to quench cells without damaging them might be a challenge... At present we are working towards developing experimental techniques to answer such questions." Additional information on this article is available at http://www.astrobio.net/news/modules.php?op=modload&name=News&file=ar ticle&sid=224 The original Science article is available at http://www.sciencemag.org/cgi/content/abstract/295/5559/1514. _____________________________________________________________________ WORLDS OF LIFE BEYOND EARTH By Pat Sheil From SpaceDaily 11 June 2002 Sometime between now and the end of the decade one of the Big Questions may well be answered. Not quite the meaning of Life, The Universe and Everything, but damn close. It seems that after decades of searching and countless centuries of wondering, we may be on the verge of finding out, once and for all, if there is life on other planets. Get the full story at http://www.spacedaily.com/news/extrasolar- 02o.html. _____________________________________________________________________ FOSSILS POINT TO ASTEROID CAUSING DINOSAURS' DEMISE By James Randerson From New Scientist http://www.newscientist.com/news/news.jsp?id=ns99992383 11 June 2002 A massive asteroid impact, not volcanic activity, caused the climate change that wiped out the dinosaurs, new fossil evidence suggests. David Beerling at the University of Sheffield and colleagues analyzed fossilized leaves from plants living before and after the extinction. The work suggests the amount of carbon dioxide in the atmosphere increased suddenly and dramatically 65 million years ago. The increase was the equivalent of injecting at least 6,400 billion tons of carbon into the atmosphere, they say--enough to warm the Earth by as much as 7.5 degrees C and dramatically change the environment. Other researchers have suggested that a series of volcanic eruptions at the Deccan Traps in India, dated to about 65 million years ago, might have prompted the climate changes that accompanied the extinction of 70 per cent of life on the planet. But only a massive asteroid impact--such as the one that left a 145 to 180-kilometre wide crater in the Yucatan peninsula in Mexico at about the same time--could have vaporized enough carbon-containing material in the Earth's crust to account for this rapid carbon dioxide increase, says Beerling's team. Small database As carbon dioxide levels in the atmosphere go up, plant's leaves have fewer pores, because it becomes easier for them to extract carbon dioxide from the air for photosynthesis. So by counting the number of pores on leaves from about 70 plants that were alive between 64 and 65.9 million years ago, Beerling's team could work out the concentration of carbon dioxide in the atmosphere at that time. "We estimate that carbon dioxide levels were four or five times higher about 10,000 years after the impact," says Beerling. "For this much carbon dioxide to come from the Deccan Traps, all the eruptions would have had to come in that time window--but we know they took more like two million," he adds. But Dewey McLean of Virginia Polytechnic Institute who proposed the volcano theory in 1981 is not convinced that Beerling can be so precise about the timing. "Their leaf database is so tiny as to be almost meaningless," he claims. Journal reference: Proceedings of the National Academy of Sciences, USA (volume 12, page 7836). _____________________________________________________________________ WHITHER EUROPA? RESEARCHERS REGROUP TO MAKE JUPITER'S MOON NASA'S PRIORITY By Leonard David From Space.com 12 June 2002 Move over Mars, researchers say Jupiter's icy moon Europa is a possible biological hot spot that's in need of close-up study. Space scientists see the moon as deserving of inspection from top to bottom--charting Europa's fractured face with ice-penetrating radar as well as deep diving below surface to probe a likely liquid ocean that could be teeming with life. Currently, a new strategy is being hammered out that calls for Europa to become a high-priority on NASA's exploration roadmap. A Europa Focus Group of leading specialists--from biologists and planetary scientists to ice experts and technologists--met here [Flagstaff, AZ] May 14-15 at the U.S. Geological Survey to discuss the prospects for an extensive survey of the Galilean satellite. Get the full story at http://www.space.com/scienceastronomy/solarsystem/europa_options_0206 12.html. _____________________________________________________________________ SALT OF THE EARLY EARTH By Leslie Mullen From Astrobiology Magazine, NASA Astrobiology Institute 12 June 2002 The next time you reach for that bag of salty chips, think for a moment about salt and life. Humans need a certain amount of salt; it is necessary for the delivery of nutrients, the transmission of nerve impulses, and the contractions of the heart and other muscles. In fact, every form of life on this planet needs salt. But why should that be? What role did salt play in the evolution of life on Earth? Scientists have long assumed that life originated in the sea. If life did spring from salt water, that could explain why all organisms use salt. But Paul Knauth, an astrobiologist with Arizona State University, says while we always assume that life came from the ocean, this theory has never been proven. He suggests we need to consider the possibility that life originated in fresh water. "Fresh" water is somewhat of a misnomer--all fresh water bodies still do contain some salt. Non-marine salt levels are less than 1 part per thousand, while marine salt levels are around 35 parts per thousand. But when life first appeared around 3.5 billion years ago, the ocean was much saltier than it is today. Estimates of the early ocean's salinity range between 1.2 to 2 times present-day salinity. "Life is stressed today in the current ocean, so one can speculate that higher salinities make things even tougher," says Knauth. Salt does seem to have played some sort of role in the origin of life--it is the precise concentration of salts that is at issue. In constructing the steps that led to the first life form, many scenarios invoke the concentration of salts through evaporation. "In the early saltier ocean, this would lead to a real devil's brew," says Knauth. However, non-marine bodies of water have a wide range of changing environments. Knauth says that some of these fresh water environments probably had the optimal salinity for the kinds of molecular assembly proposed for the origin of life. Shiladitya DasSarma, a professor at the University of Maryland Biotechnology Institute, Center of Marine Biotechnology, agrees that life could have originated in fresh water pools. So long as these pools had a certain amount of organic molecules, prebiotic evolution could have occurred. However, DasSarma thinks that life also could have begun in the early salty ocean. He has found that, due to the low water activity of hypersaline brines, macromolecules can form from organic molecules. A macromolecule is a very large molecule, such as a protein or other polymer. The macromolecules in these salty waters, combined with other molecules, could have formed membranes capable of Darwinian evolution (and thus be classified as a life form). Liquid water began accumulating on the surface of the Earth about 4 billion years ago, forming the early ocean. Most of the ocean's salts came from volcanic activity or from the cooled igneous rocks that formed the ocean floor. This volcanic activity also created island chains that grew over time. Tectonic plate movement caused these islands to collide, forming the cores of the continents. The continents developed fresh water lakes and ponds through rainfall and other meteorological processes. Soon after both salty water and fresh water were available, life originated. The oldest fossils we have are from 3.5 billion-year-old cyanobacteria, but life probably emerged even earlier than that. Genetic analysis has shown that the archaean branch of life came first, appearing sometime before bacteria. One form of archaea is adapted to live in high-salt environments. Known as "halophiles" ("salt lovers"), these organisms live in wet salty environments such as the Dead Sea and Utah's Great Salt Lake. If halophiles were found to be the most ancient archaeans, the origin of life would point toward very salty water. The specific antiquity of halophiles is not currently known, but because they "breathe" oxygen they are not believed to be one of the earliest forms of archaea. Oxygen wasn't a major component of the Earth's atmosphere until anaerobic organisms like cyanobacteria began producing it. However, DasSarma has some evidence that halophiles may lie very deeply in the tree of life. DasSarma and his team have recently sequenced the genome of an extreme halophile called Halobacterium species NRC-1. DasSarma says that when the genes of Halobacterium NRC-1 are compared to other organisms, this halophile seems to be the most ancient archaean. "This is very unexpected," says DasSarma. "The small ribosomal RNA- based trees pointed to halophiles as recent relatives of a class of anaerobic archaea called methanogens, which have very simple metabolism involving methane production from inorganic gases." DasSarma says the close relationship between halophiles and methanogens never made sense because they do not share physiological capabilities: halophiles need oxygen; methanogens do not. But it turns out halophiles are able to produce energy without oxygen in two ways: from the degradation of arginine, and by using the photosynthetic molecule bacteriorhodopsin. Perhaps these two methods of non-oxygen energy production are the last remnants from the halophile's earlier, anaerobic days. As the Earth's oxygen levels rose 2 billion years ago, the gas would have killed off many anaerobic organisms. In a process called "lateral gene transfer," halophiles may have borrowed genes from aerobic bacteria in order to survive this increase in oxygen. "Our analysis of genes in halophiles suggest common ancestry with many bacterial genes, for example, those involved in aerobic respiration," says DasSarma. "Whether these are recently acquired by lateral gene transfers or have common ancestry with bacteria is currently being analyzed." The rise of oxygen as an atmospheric gas changed the face of life on Earth. Many life forms died out, while other life forms adapted to the new gas. But Knauth says the early ocean wouldn't have absorbed very much of this oxygen. If the ocean was warm in its early days-- and Knauth believes that the ocean 3.5 billion years ago was like hot tap water--then the combination of high temperature and high salinity would have resulted in an ocean with very little dissolved oxygen. Oxygen-use has been linked with the development of complex life forms. Therefore, Knauth says the ancient, anoxic sea would have housed only the simpler organisms like anaerobic bacteria, while aerobic organisms and other complex life forms evolved in fresh water. But another dramatic environmental change was on the horizon: the formation of the continents led to a process that reduced the amount of salt in the ocean. Ocean waters sometimes flooded low- lying continental areas, but these shallow seas evaporated relatively quickly--in about 100 million years. The minerals left behind formed large salt basins, and this sequestered salt resulted in lower ocean salinity. As the ocean cooled and salt basins began to form, the ocean would have been able to absorb more oxygen. This oxygen absorption opened up a new environmental niche for aerobic organisms, and the sea would have seen an explosion of new life forms. In fact, if the salt basins formed around 540 million years ago, Knauth believes ocean salt levels could have had a hand in the Cambrian Explosion. Scientists still have not figured out what triggered the enormous increase in the diversity of life in the Cambrian era. But salt basins, forming in a brief period of time and decreasing the salinity of the oceans, would have had a profound impact on life. "The currently favored view for the major control on the Cambrian explosion of life is that atmospheric oxygen levels built up until metazoan life was possible," says Knauth. "These larger organisms need higher oxygen levels to survive. My point is that it is dissolved oxygen that is critical here, not just the atmospheric level. The arrival of big salt deposits on the continents in the latest Precambrian could have been one of the key factors that allowed the shallower oceans to finally oxygenate enough for metazoans to take to the sea." The role of salt in the origin and evolution of life is still an open question. To find answers, Knauth says scientists need to take a closer look at the depositional environments of sedimentary rocks that hold Precambrian microfossils. But what if the answer is not to be found in the rocks of Earth? If halophiles turn out to be the most ancient life form, perhaps we need to look at the red rocks of Mars for our answers. Mars originally had much more salt than the Earth, and when Mars lost 50 to 90 percent of its water through evaporation it became even saltier. The Panspermia [hypothesis] says that life originated elsewhere and then was transferred to Earth by meteors. If the earliest life forms were halophiles, says Knauth, then perhaps we are really Martians. DasSarma finds the idea of halophilic life on Mars a fascinating concept. He says it may be possible to look for such life on Mars today. "If indeed Mars is salty and life could have evolved there, it may still be trapped in brine inclusions within salt crystals," says DasSarma. "Another property of earthly halophiles that may have some bearing on their ability to survive is that these organisms are extremely resistant to solar radiation, and therefore would be excellent candidates for interplanetary travel." What next? DasSarma suggests it may be possible to discover what halophiles were like in their early days by studying salt bitterns: hypersaline brines that are left after the commercial production of salt. Like the early ocean, salt bitterns are anoxic as well as extremely salty. "It is intriguing that the intracellular salt concentrations of modern halophiles resemble the potassium-enriched, sodium-depleted bitterns remaining after the harvesting of marine salt," says DasSarma. DasSarma says it may be possible to create a "prebiotic soup" of organic and inorganic components along with brine from a bittern. This mixture perhaps could allow growth of modern halophiles exhibiting some of their primordial capabilities. Knauth, meanwhile, is working on the question of whether life evolved in the ocean and adapted to lower salinity environments, or whether life evolved in fresh water and then adapted to life in the oceans. He is looking at the fossil record of various non-marine environments to try to answer this question, and has found some very promising sites in Australia. "Currently I'm exploring life on land in the Precambrian," says Knauth. "I'm looking at non-marine environments to see if the fossil record indicates whether life could have originated in that environment rather than in the sea, as we've always thought." Additional information on this article is available at http://www.astrobio.net/news/modules.php?op=modload&name=News&file=ar ticle&sid=223. _____________________________________________________________________ ASTRONAUT FINGERS By Tony Phillips and Steve Price From NASA Science News 12 June 2002 When Mary Etta Wright was a child, she loved to experiment. She mixed powders from her chemistry set, took apart the family radio... and, oh yes, there was that time when she dropped (and shattered) her father's piggy bank. "It seemed I was always getting in trouble," laughs Wright. "But touching things was how I learned about them." Now Wright, who works at NASA's Microgravity Development Lab at the Marshall Space Flight Center, is helping astronauts get their hands on things, too. She's the lead engineer for the Microgravity Science Glovebox--a device that will allow astronauts to reach in and touch some of the amazing experiments onboard the International Space Station (ISS). "Humans are natural scientists," says Wright. "We can observe, react to the unexpected and tinker with things to squeeze the most out of any experiment." Yet until now, that was often impossible on the ISS. Many experiments took place inside sealed compartments, and reaching in was not allowed. The barriers were for the crew's own good. Liquids in zero-g, for example, don't always stay in their test tubes. And if fumes get thick, astronauts can't throw open the nearest window for fresh air. Floating contaminants pose a danger to the crew and to the station itself--they must be contained. Scientists needed something that would keep contaminants in... yet not keep astronauts out. The solution is the ESA-built Microgravity Science Glovebox, or "MSG" as it's known around NASA. The glovebox is a tightly sealed aluminum chamber... with hands. "The MSG is about the size of a spacious juke box," says Wright. There's room for experiments as large as 255 liters (67 gallons). Astronauts can reach into the chamber using rubber gloves attached to the front and sides. Large windows made of Lexan (a tough plastic widely used on Earth for items ranging from water bottles to bus stops) provide a clear view of what's happening inside. "It's a beautiful setup, like a small laboratory," says Aleksander Ostrogorsky, a professor at the Rensselaer Polytechnic Institute who will soon use the glovebox to study semiconductors. The glovebox is laid out much like a traditional lab bench. There are power supplies, vacuum ports and computer interfaces. The familiar arrangement helps scientists design space-experiments using their own lab benches on Earth. Human participation allows for simpler designs. Experiments can be developed for the glovebox within two to three years at a fraction of the cost of totally automated systems. This isn't the first time a glovebox has flown to space. Astronauts have used them on NASA's space shuttle and on the Russian space station Mir. But the MSG is bigger and better than its predecessors in many ways. For example, cameras mounted inside the MSG can transmit live images to Earth, where scientists can monitor and even control their own experiments. As a result, astronauts and scientists form a team of creative, brainstorming co-workers-- "something we couldn't do before," says Wright. Scientists are looking forward to using the MSG for many things--to probe the physics of fluids, the strange behavior of flames, the inner workings of cells, the growth of tissues... the list goes on and on. Some of the experiments slated for flight are so cutting- edge they sound more like science fiction than ordinary science. Imagine, for example, a fluid that stiffens when you hold a magnet near it, and softens again when the magnet goes away. Sounds amazing, but it's a real effect. An upcoming experiment called InSPACE will use the glovebox to explore these exotic liquids, called "magnetorheological fluids." The possibilities are mind-boggling. In theory, surfaces coated with such fluids could change form at the bidding of magnetic controls. A single magnetorehelogical mold could cast an infinite variety of shapes. Book makers could publish magnetic texts in Braille--as easily scrolled and edited as words on a computer screen. Medical engineers could build magnetorheological limbs that bend and move as if alive. "But first," cautions Jack Lekan, the project manager for InSPACE at the Glenn Research Center, "we have to learn more about the basic physics of these fluids." That's what InSPACE aims to do. During the experiment, astronauts will observe what happens when a floating magnetorehelogical fluid is exposed to magnetic pulses. To collect the data scientists need, astronauts will reach into the glovebox to align and focus cameras on a spot only 0.2 mm wide. If a fluid bubble gets in the way of the shot... flick! They can remove it. "Astronauts are an integral part of our study," says Lekan. Shuttle Endeavour (STS-111) delivered the glovebox to the space station this week--good news for scientists on Earth and for the station's crew. Says Wright, "astronauts love doing hands-on experiments." And now they can. The Microgravity Science Glovebox was built for NASA by the European Space Agency (ESA). In exchange, the ESA will be able to use other facilities inside the Destiny lab until that agency's own laboratory- -the Columbus Orbital Facility--is attached to the space station in a couple of years. Additional information on this article is available at http://science.nasa.gov/headlines/y2002/12jun_fingers.htm?list52260. _____________________________________________________________________ LONG-DURATION ASTRONAUTS NEED PEOPLE SKILLS By William Harwood From Spaceflight Now 12 June 2002 To understand what's it's like to make a long-duration voyage aboard the international space station, imagine taking a really long trip in a car. And then imagine never getting a chance to stop or step outside, even if your traveling companion is driving you up the wall. "I don't care who you fly with, it could be your best friend, there are going to be times where you get on each other's nerves," said station astronaut Daniel Bursch, wrapping up a record 194-day stay in space. "That happens, and you find a way to deal with it, whether its exercise or be by yourself or work on a hobby." Get the full story at http://spaceflightnow.com/station/sts111/020612crew/. _____________________________________________________________________ EXTRATERRESTRIAL JUPITER From NASA Science News 13 June 2002 Today astronomers announced the discovery of more than a dozen new planets orbiting distant stars. One of those planetary systems looks a bit like our own. After 15 years of looking, a top planet-hunting team has finally found a distant planetary system that reminds them of home. Geoffrey Marcy, astronomy professor at the University of California, Berkeley, and astronomer Paul Butler of the Carnegie Institution of Washington today announced their discovery of a Jupiter-like planet orbiting a Sun-like star at nearly the same distance as the real Jupiter orbits our own Sun. Astronomers had found Jupiter-like planets around other stars before. But they were all very close to their parent suns (astronomers called the planets "hot Jupiters") and their orbits were elongated--not circular. "This new planet orbits as far from its star as our own Jupiter orbits the Sun," said Marcy. That's what makes it interesting. The star, 55 Cancri in the constellation Cancer, was already known to have one planet, announced by Butler and Marcy in 1996. That planet is a gas giant slightly smaller than the mass of Jupiter. It whips around the star in 14.6 days at a distance of only 0.1 AU. (AU means "astronomical unit." It's the distance between Earth and the Sun-- approximately 93-million miles. So, the first planet found in the 55 Cancri system is only one-tenth as far from its star as Earth is from the Sun.) The newfound planet, announced today, orbits 55 Cancri at 5.5 AU, comparable to Jupiter's distance from our Sun of 5.2 AU. Its slightly elongated orbit takes it around the star in about 13 years, comparable to Jupiter's orbital period of 11.86 years. It is 3.5 to 5 times the mass of Jupiter. The star 55 Cancri is 41 light years from Earth and is about 5-billion years old--about the same age as our own Sun. "We haven't yet found an exact solar system analog, which would have a circular orbit and a mass closer to that of Jupiter. But this shows we are getting close, we are at the point of finding planets at distances greater than 4 AU from the host star," said Butler. "I think we will be finding more of them among the 1,200 stars we are now monitoring." The team shared its data with astronomer Greg Laughlin at the University of California, Santa Cruz. His dynamical calculations show that an Earth-sized planet could survive in a stable orbit between the two gas giants. For the foreseeable future, existence of any such planet around 55 Cancri will remain speculative. "This planetary system will be the best candidate for direct pictures when the Terrestrial Planet Finder is launched later this decade," added UC Berkeley astronomer Debra Fischer. Marcy, Butler, Fischer and their team also announced a total of 13 new planets today, including the smallest ever detected: a planet circling the star HD49674 in the constellation Auriga at a distance of .05 AU, one-twentieth the distance from Earth to the Sun. Its mass is about 15 percent that of Jupiter and 40 times that of Earth. This brings the number of known planets outside our solar system to more than 90. More information on this article is available at http://science.nasa.gov/headlines/y2002/13jun_newplanets.htm?list6924 7. Additional articles on this subject are available at: http://www.astrobio.net/news/modules.php?op=modload&name=News&file=ar ticle&sid=225 http://www.cnn.com/2002/TECH/space/06/13/new.planets/index.html http://www.space.com/scienceastronomy/astronomy/planet_discovery_0206 13.html _____________________________________________________________________ WHAT TO SAY WHEN ET FINALLY CALLS By Douglas Vakoch From Space.com 13 June 2002 Over the past forty years, astronomers have intermittently observed the heavens with radio telescopes, looking for signs of intelligent life around distant stars. During its early decades, this search was limited by the amount of time available on major telescopes, as well as signal processing capability. Only recently, with more powerful search programs such as the SETI Institute's Project Phoenix, have we conducted more comprehensive searches. Even so, the most sensitive searches proceed star by star--a process requiring considerable patience. Given these constraints, it is hardly surprising that we have not yet discovered intelligence beyond Earth. But with SETI Institute's Allen Telescope Array slated for completion in 2005, we will soon have a world-class radio telescope scanning the skies twenty-four hours a day, seven days a week. It's possible that the search will continue for centuries, with no indication that intelligence exists beyond Earth. It's also possible that astronomers will detect ET tomorrow. What then? What will we do if we succeed? Get the full story at http://www.space.com/searchforlife/seti_vakoch_message_020613.html. _____________________________________________________________________ NEW ADDITIONS TO THE ASTROBIOLOGY INDEX By David J. Thomas http://www.lyon.edu/webdata/users/dthomas/astrobiology/astrobiology.h tml 17 June 2002 Astrobiology, exobiology and terraformation articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_article s1.html R. R. Britt, 2002. Jupiter-like planet could point to another Earth. Space.com. L. David, 2002. Whither Europa? Researchers regroup to make Jupiter's moon NASA's priority. Space.com. NASA Headquarters, 2002. Extraterrestrial Jupiter. NASA Science News. NASA Headquarters, 2002. Newfound planetary systems: "hometown" look. Astrobiology Magazine. P. Sheil, 2002. Worlds of life beyond Earth. Spacedaily. R. Stenger, 2002. Planetary system found that resembles ours. CNN. Terrestrial extreme environments articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_article s2.html Astrobiology Magazine staff, 2002. High-pressure living. Astrobiology Magazine. Human space exploration and microgravity effects articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_article s3.html W. Harwood, 2002. Long-duration astronauts need people skills. Spaceflight Now and CBS News. T. Phillips and S. Price, 2002. Astronaut fingers. NASA Science News. Search for extraterrestrial intelligence (SETI) articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_article s4.html D. Vakoch, 2002. What to say when ET finally calls. Space.com. Evolutionary biology and chemistry articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_article s5.html J. L. Bada and A. Lazcano, 2002. Some like it hot, but not the first biomolecules. Science, 296(5575):1982-1983. S. C. Dawson and N. R. Pace, 2002. Novel kingdom-level eukaryotic diversity in anoxic environments. Proceedings of the National Academy of Sciences, USA, 99(12):8324-8329. M. E. Kotyk, J. F. Basinger, P. G. Gensel and T. A. de Freitas, 2002. Morphologically complex plant macrofossils from the Late Silurian of Arctic Canada. American Journal of Botany, 89(6):1004-1013. J. Randerson, 2002. Fossils point to asteroid causing dinosaurs' demise. New Scientist. D. Williamson, 2002. Fossils found in arctic shows plants more developed at earlier time. SpaceDaily. _____________________________________________________________________ CASSINI SIGNIFICANT EVENTS NASA/JPL release 6-12 June 2002 The most recent spacecraft telemetry was acquired from the Goldstone tracking station on Wednesday, June 12. The Cassini spacecraft is in an excellent state of health and is operating normally. Information on the present position and speed of the Cassini spacecraft may be found on the "Present Position" web page located at http://saturn.jpl.nasa.gov/cassini/english/where/. On-board activities were light this week and will remain so as Cassini passes through solar conjunction. Events included a clearing of the High Water Marks and an autonomous CDS Solid State Recorder memory load partition repair. As part of last week's Spica observations, 26 Narrow Angle Camera, and 2 Wide Angle Camera images were collected along with 41 Visual and Infrared Mapping Spectrometer cubes. Analysis of last week's Imaging Science Subsystem diagnostic imaging was inconclusive due to the small amount of cooling time before the images were taken, and to the loss of some data during transmission. Data in some filters looked slightly improved and some looked slightly worse. Data taken at -40C has more noise than -90C data. This complicates ongoing analysis and comparison activities. The Radio Science Subsystem Solar Conjunction Experiment is underway and will continue until early July. For the first three days there were technical difficulties at the Goldstone DSN complex resulting in loss of data. By Sunday operations were nominal and the experiment continued as planned. The Spacecraft Operations Office delivered version 8.0.1 of the Kinematic Prediction Tool/Inertial Vector Propagator software. This is a maintenance delivery to be integrated into the Mission Sequence Subsystem software in support of Science Operations Plan development. Mission Support and Services Office personnel successfully installed the new software. The Attitude Control Flight Software team delivered version A8.6.0. This is the "hard freeze" version. The only planned updates are parameter changes for the critical sequences. An Operational Readiness Review was held for Cassini's use of the new Command System. Approval was given to make the new Command System the default standard for all Cassini commanding starting with the beginning of the Solar Conjunction Experiment. The old Command System is still available for contingency commanding should there be a need to revert from the new system. Cassini Outreach met with its kindergarten-4th grade partners to finalize plans and the long-term objectives in the K-4 language & reading program. This new program will be the cornerstone in Cassini's elementary education initiative. Mission Assurance and the implementers of the Cassini online Risk Management Tool discussed and agreed upon the several sets of automated metrics to be included in the tool. A schedule has been established that shows the additions completed by the end of the fiscal year. These metrics will be used to illustrate the Program's risk posture given intervals, and will be presented at Monthly and Quarterly Management Reviews. In addition to the metrics, several minor modifications were also agreed upon, to ensure consistency between the online tool and the Risk Management Plan. 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. _____________________________________________________________________ INTERNATIONAL SPACE STATION EXPEDITION FOUR SCIENCE OPERATIONS STATUS REPORT NASA/MSFC release 02-148 12 June 2002 Working ahead of schedule, Space Station and Space Shuttle crews during the past week have almost completed moving new Expedition Five science experiments and lab equipment into the Station and transferring completed experiments to the Shuttle for waiting scientists on the ground. On Saturday, crews moved the new EXPRESS Rack 3 from the Leonardo Multi Purpose Logistics Module into position in the Station's Destiny laboratory. There are now five floor-to- ceiling EXPRESS experiment racks in the lab. The racks, built by Boeing at NASA's Marshall Space Flight Center in Huntsville, provide experiments with basic utilities such as power, communications, cooling, and fluids. Like EXPRESS Rack 2 already on board, Rack 3 is equipped with the Active Rack Isolation System for protecting delicate microgravity experiments inside from vibrations caused by crew movement and operating equipment. Transferred inside the rack was the Microencapsulation Electrostatic Processing System (MEPS) experiment. On Sunday, the crew transferred the Microgravity Science Glovebox to the Destiny lab, a day ahead of schedule. The glovebox is a sealed container with built-in gloves that will make it possible for crews to do more hands-on science experiments involving fluids, flames, particles, and fumes. The gloves allow crews to change samples, adjust video and perform other operations in a sealed atmosphere. The Payload Operations Center will be working with the crew to complete the Glovebox's installation and checkout during the first week in July. The Glovebox was built by the European Space Agency with help from engineers in the Microgravity and Applications Department at Marshall. Two Glovebox experiments were also transferred from the Shuttle to the Station during the past week. The Solidification Using a Baffle in Sealed Ampoules (SUBSA) experiment places samples in a furnace inside the Glovebox to study production of semiconductor materials. The Pore Formation and Mobility Investigation experiment also uses a furnace inside the Glovebox to examine the formation and movement of bubbles in molten materials in microgravity. Last Thursday aboard the Station, one day after the Shuttle lifted off, the Expedition 4 crew planted the last set of wheat seeds in the Biomass Production System (BPS), a plant growth system developed by Orbital Technology Corp, Madison, WI, for the Space Station Biological Research Project at NASA's Ames Research Center, Moffett Field, CA. The crew then transferred BPS to the Shuttle on Saturday. The seeds from this fast-growing hybrid were expected to germinate and grow while the Shuttle is docked with the Station. When Endeavour returns to Earth, the scientists from Orbital Technology Corp and Kennedy Space Center will harvest the plants and compare it with other plants grown during the two months that the BPS was on-orbit. On Friday, the crew moved the new ARCTIC 2 freezer from the logistics module to a temporary location next to EXPRESS Rack 4. ARCTIC is used to preserve biological samples after processing until they can be returned to Earth. They also transferred the Commercial Generic Bioprocessing Apparatus from the Station to the Shuttle for return to Earth. On Saturday, the crew transferred the Protein Crystal Growth Single Thermal Enclosure System (PCG-STES) experiment from Endeavour to the Station and activated it on Sunday. Crystals of biological substances will be grown during the Expedition. Frozen human liver cells and the media pouches to support the StelSys investigation of those cells functioning in microgravity were transferred from the Shuttle to the Station on Saturday. The cells are kept frozen in a liquid nitrogen dewar, and the media pouches were placed in the ARCTIC 1 refrigerator on the ISS. The dewar will maintain the viability of the liver cells until they are injected into the media pouches on June 18 for incubation in the Biotechnology Specimen Temperature Controller. On Sunday, Flight Engineer Dan Bursch conducted pre-spacewalk readings of the EVA Radiation Monitoring experiment dosimeter badges worn by STS-111 crewmwmbers Franklin Chang-Diaz and Philippe Perrin during their spacewalk later that day. Also on Sunday, the crew transferred the Advanced Astroculture commercial plant growth experiment from the Shuttle into the Station and activated it on Tuesday, initiating the germination of soybean seeds for a planned growth period of 71 days. On Monday, the Experiment on Physics of Colloids in Space was transferred to a temporary location in the logistics module for later stowage and return to Earth. Crew Earth Observations (CEO) photography subjects during the past week included vegetation and coastal dunes in Somalia, Amazon delta wetlands, and reefs and lagoons of the Tuamotu Archipelago. Eleven experiments are completed and scheduled for return aboard the Shuttle. Another 11 continue operating aboard the Station, joined now by four all-new Expedition Five experiments, two re-flights of earlier experiments and additional research samples for research facilities already on board. Ahead this week, the crew will transfer the Protein Crystal Growth Enhanced Gasseous Nitrogen dewar experiment from the Station to the Shuttle for return on Saturday. The upcoming week is an unusually good time for people in North America to spot the International Space Station docked with Space Shuttle Endeavour. For more information, please click on http://www.spacescience.com/headlines/y2002/10jun_spaceship.htm. _____________________________________________________________________ MARS ODYSSEY THEMIS IMAGES NASA/JPL/ASU release 10-14 June 2002 * Streamlined Islands in Ares Valles (Released 10 June 2002) http://themis.la.asu.edu/zoom-20020610a.html * Gullies of Gorgonus Chaos (Released 11 June 2002) http://themis.la.asu.edu/zoom-20020611a.html * Northwestern Branch of Mangala Vallis (Released 12 June 2002) http://themis.la.asu.edu/zoom-20020612a.html * Floor of Baldet Crater (Released 13 June 2002) http://themis.la.asu.edu/zoom-20020613a.html * Impact Crater with Peak (Released 14 June 2002) http://themis.la.asu.edu/zoom-20020614a.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. Dr. Philip Christensen leads the THEMIS investigation at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena. _____________________________________________________________________ STARDUST STATUS REPORT NASA/JPL release 14 June 2002 There was one Deep Space Network tracking pass on Tuesday, June 11, and all subsystems are performing normally. The power subsystem's performance continues to be excellent. The spacecraft is currently 298 million kilometers (182 million miles) from Earth and has traveled over 2.2 billion kilometers (1.4 billion miles) around the Sun since its launch in February 1999. In 567 days, Stardust will encounter Comet Wild 2 in January 2004. 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 22.