MARSBUGS: The Electronic Astrobiology Newsletter Volume 9, Number 29, 13 August 2002. Editor/Publisher: David J. Thomas, Ph.D., Science Division, Lyon College, Batesville, AR 72503-2317, USA. dthomas@lyon.edu Contributing Editor: Julian A. Hiscox, Ph.D., 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) ARE YOUNG SOLAR NEBULAE NURSERIES FOR MICROORGANISMS? By Michael Mautner 2) ESA AT THE WORLD SUMMIT ON SUSTAINABLE DEVELOPMENT ESA release 55-2002 3) SICK OR SLEEPY--NO OPTION IN OUTER SPACE National Space Biomedical Research Institute release 4) JUPITER UNCLOAKS: MOST MOONS EVER FOUND AT ONCE From Astrobiology Magazine 5) ONE SMALL STEP... BUT ONLY ON A HOSPITABLE PLANET! From ESA Science News 6) TO DISTILL SOME WATER By Trudy E. Bell and Tony Phillips 7) TRADITIONAL CHINESE MEDICAL HERBS GET BOOST FROM SPACE TRAVEL From SpaceDaily and Agence France-Presse 8) WEIRD LIFE ON THE MATS By Lee J. Siegel 9) NEW ADDITIONS TO THE ASTROBIOLOGY INDEX By David J. Thomas 10) CASSINI SIGNIFICANT EVENTS NASA/JPL release 11) THE NEXT FOUR WEEKS ON GALILEO NASA/JPL release 12) INTERNATIONAL SPACE STATION SCIENCE OPERATIONS STATUS REPORT NASA/MSFC release 02-199 13) MARS GLOBAL SURVEYOR MARS ORBITER CAMERA (MOC) 2002 SOLAR CONJUNCTION SAMPLER NASA/JPL/MSSS release 14) MARS ODYSSEY THEMIS IMAGES NASA/JPL/ASU release 15) STARDUST SPACECRAFT REACHES FOR COSMIC DUST NASA/JPL release 16) STARDUST STATUS REPORT NASA/JPL release _____________________________________________________________________ ARE YOUNG SOLAR NEBULAE NURSERIES FOR MICROORGANISMS? By Michael Mautner 5 August 2002 New evidence suggests that conditions hospitable to life may have existed in the early Solar System, even before the planets became habitable. If so, similar solar nebulae could sustain and disperse life through the galaxy by natural or directed panspermia. Further, the remaining materials in asteroids and comets can support vast human populations in the Solar System. To examine these proposals, we have been pursuing a research program in experimental astroecology--measuring nutrients in planetary materials, and biological responses to these nutrients. These studies use small planetary microcosms based on asteroid and Martian materials that are represented by meteorites. The experiments involve extracting nutrients and growing microorganisms, algae and plant tissue samples on these materials. The formation of solar systems starts with solar nebulae--gas and dust from a collapsed interstellar cloud--that form stars and planets. Could life have existed early in the early solar nebula before the Earth and (possibly) Mars became habitable? Carbonaceous asteroids in the early Solar System contained liquid water. This is evidenced by water-processed phyllosilicate materials in CM2 meteorites, and also by the presence of soluble salts. The solutions in these early asteroid pores can be reconstructed by adding 10% water to the crushed meteorites, about equal to the amount of water that filled the pores of the early asteroids. We found that the reconstructed solutions are highly concentrated, containing (in units of mg/liter or ppm): calcium, 14,000 mg/L, magnesium, 17,000, sodium 19,000, potassium 1,100, sulphate 57,000. Also present are biologically useful concentrations of the essential plant/algal nutrients nitrate, phosphate and iron. In total, these solutions contain about the same salinity as the early oceans, although possibly of a different composition. Significantly, these solutions also contained fairly concentrated solutions, about 10 g/liter, of organics. The organics were trapped for long periods in the internal pores of the early asteroids, and exposed to temperatures over 100 C and catalytic electrolytes and minerals. Under these conditions, the trapped organics had time to build up complex biomolecules, and maybe the first microbes. Once life arises, or is introduced to, the solutions in these asteroids, they can support the growth of microrganisms, especially halophiles that seem to have been the earliest microorganisms (Leslie Mullen, Marsbugs 17 June 2002). Evidence for possible early life in carbonaceous asteroids includes: 1. The relative amounts of the essential elements carbon, nitrogen, phosphorus and potassium in CM2 meteorites are similar to those in biological matter. 2. Biological molecules such as amino acids and adenine are present in meteorites, although mixed with non-biological organics. 3. Organic polymers are present that resemble kerogens of biological origin. 4. Structures resembling fossilized blue-green algae were reported in the meteorites (Claus and Nagy, 1961; Harold Urey, 1962; and Richard Hoover in recent research). It is also noteworthy that life appeared on Earth soon after the end of Late Bombardment, when large amounts of impacting asteroids and comets could have imported microorganisms. To examine whether microorganisms can survive in the asteroid internal solutions, we inoculated these reconstructed solutions and actual wetted meteorites with microorganisms from a wetland. We found that several soil microorganisms, including Nocardia asteroides and Pseudomonas fluorescens, as well as fungi, could grow on the meteorites to populations up to 10 million per milliliter, similar to those in soil solutions. Several types of algae, including filamentous blue-green cyanobacteria, also grew well in these solutions, and are still surviving after more than a year. It therefore appears that the early Solar System contained habitats where life could originate, and nutrient environments where microorganisms can multiply. Moreover, frequent collisions amongst the early asteroids can disperse microorganisms throughout the early asteroid belt. The results have implications about panspermia and about future life in space. A large number of asteroids and comets were ejected from the early Solar System to interstellar space. If the Solar Nebula hosted microorganisms, the ejected asteroids and comets would have carried them into deep space, some possibly landing in other solar systems. The same resources, preserved from the early Solar Nebula, are still present in the asteroid belt, and in larger amounts in the comets. We measured the amounts of bioavailable nutrients in carbonaceous meteorites. Based on the results, soils derived from the carbonaceous asteroids can sustain a biomass of 10^18 kg. This biomass in turn can support a human population of one hundred trillion, equivalent to 10,000 Earths. Solar nebulae can be also used as vehicles for expanding life in the galaxy. A panbiotic, life-centered ethics may motivate such as program, based on the uniqueness of life in nature, the basic unity of all organic gene/protein life, and of ourselves belonging to this family of organic Life. In the near future, we will have the technology to undertake such programs, sending microbial payloads to new solar systems in star-forming interstellar clouds. Later, if materials from the Oort Belt comets can be accessed, they contain enough organic material for seeding every new planetary system in the galaxy. Extremophile microorganisms with high chances of survival can be bioengineered for such missions. In fact, our experiments with genetically modified Pseudomonas fluorescens showed that a genetically modified microorganism can use meteorite organics. The panspermia payloads can also include simple multicellular organisms. After capture by asteroids and comets in the new solar nebulae, some may land on planets when they are habitable to multicellular species. Eventually, some of these new branches of life may evolve into intelligent life-forms who will propagate life further in the galaxy. Experimental results on the astroecolgy of asteroids/meteorites therefore suggest that solar nebulae contain suitable conditions and materials for the origins of life. Native or introduced microrganisms can multiply and disperse in the asteroid belt, and beyond the Solar System. Once planted naturally or by design in new solar nebulae, the process can repeat itself, possibly leading to exponential growth. In this manner, solar nebulae can be vehicles for dispersing life in the galaxy. Resources from the solar nebula, stored in asteroids, can also support large-scale future human expansion. The first results in experimental astroecology suggest that solar nebulae as vehicles for life merit further research. This article was abstracted from: M. N. Mautner, 2000. The Purpose and Future of Life: The Science of Ethics of Seeding the Universe (www.legacy-books.com) M. N. Mautner, 2002. Planetary resources and astroecology... implications for space populations and panspermia. Astrobiology, 1:59-76. M. N. Mautner, 2002. Planetary resources and astroecology: Planetary microcosm bioassays of martian and carbonaceous chondrite materials: Nutrients, electrolyte solutions, and algal and plant responses. Icarus, 158:72-86. Preprint available at www.astroecology.com. Additional information on directed panspermia is available at www.panspermia-society.com . Contact: Michael Mautner E-mail: mautnerm@lincoln.ac.nz _____________________________________________________________________ ESA AT THE WORLD SUMMIT ON SUSTAINABLE DEVELOPMENT ESA release 55-2002 6 August 2002 The World Summit on Sustainable Development (WSSD) is being held in Johannesburg between 26 August and 4 September. ESA will be present at this important gathering aimed at finding practical responses to the challenges of improving the lives of all human beings while protecting the environment. History In 1972, with the convening of the UN Conference on the Human Environment, held in Stockholm, the environment became an international issue. In June 1992 Brazil hosted the United Nations Earth Summit in Rio de Janeiro at which governments adopted Agenda 21, a global action plan for sustainable development. The Earth Summit was attended by 50 000 delegates including 103 Heads of State, 2000 journalists. Agenda 21, containing over 2500 wide-ranging recommendations for action, broke new ground in integrating environmental, economic and social concerns into a single policy framework. The concept of sustainable development was born. By adopting Agenda 21, developed countries, which had benefited immensely from a wasteful and hazardous path of modernization, would help developing countries combat poverty and avoid that same polluting path. At the next Earth Summit, in 1997, governments agreed on a program of action for further implementation of Agenda 21. In December 2000 the UN General Assembly decided to hold a World Summit on Sustainable Development in 2002, to reinvigorate at the highest political levels the global commitment to sustainable development agreed upon ten years earlier in Rio. This year's World Summit will be held in Johannesburg between 26 August and 4 September, its main objective being for today's world leaders to adopt concrete measures and identify quantifiable targets for better implementation of Agenda 21. In addition to governments, the Summit will be attended by representatives of business and industry, children and youth organizations, farmers, indigenous people, local authorities, non-governmental organizations, scientific and technological communities, workers and trade unions. The role of space in sustainable development In the words of the UN Secretary General "At its core, Johannesburg is about the relationship between human society and the natural environment". Society demands and deserves more protection against natural and man-made disasters such as floods, storms, earthquakes, pollution, fires and explosions. There is increasing concern about the implications of global warming. All this is linked to environmental security, which is about controlling diseases, safeguarding the quality of the food we eat and the water we drink, preventing disasters, anticipating climate change and managing natural resources. Space applications contribute to sustainable development by providing information, measurements and quantifications of natural or artificial phenomena. ESA satellites of today (ERS-2, Envisat) and the near future are ideal tools for global surveillance, since they can provide a continuous, reliable stream of environmental data to monitor the atmosphere, oceans and landmasses, complementing ground- based data. Space applications facilitate observation, measurement, surveillance and communication, and constitute the core of a global environmental intelligence system capable of modeling, explaining and predicting planetary developments. Thanks to Earth-observing satellites, for instance, it becomes possible to save rain forests, protect and manage agricultural systems, find water and combat desertification. The International Charter on Space and Major Disasters, initiated in 1999 by ESA and the French Space Agency (CNES) and later subscribed by the Canadian Space Agency (CSA), the Indian Space Research Organization (ISRO) and the National Oceanographic and Atmospheric Administration (NOAA), is another positive response from the space community to Agenda 21 recommendations. Through this Charter, international space-based resources are immediately deployed to monitor natural disasters and for instance identify both possible and impossible access routes for humanitarian and relief teams. Space-based positioning systems like GPS and Europe's Galileo will soon be employed to bolster security of aircraft and airport zones, and to provide a full picture of hazardous goods shipments worldwide. All these needs are addressed by GMES (Global Monitoring for Environment and Security). This European initiative is led by ESA and the European Commission and involves national space agencies, industry and the scientific community. The objective is to coordinate space programs and non-space-borne Earth observation and environmental observation systems with national and Commission R&D efforts and the needs of potential users. ESA is sending a delegation of experts to the Johannesburg Summit. The concept of the usefulness of space technologies and applications contributing to sustainable development has been included in the draft Plan for Implementation to be finalized at the Summit. An exhibition highlighting the Agency's main programs will be located in Ubuntu Village, at the heart of the Summit venue. For further information: ESA Media Relations Phone: +33 1 5369 7713 Fax: +33 1 5369 7690 For further information on ESA at WSSD, contact: Micheline Tabache, ESA International Relations Department Phone: +33 1 5369 7304 Fax: +33 1 5369 7626 E-mail: Micheline.tabache@esa.int _____________________________________________________________________ SICK OR SLEEPY--NO OPTION IN OUTER SPACE National Space Biomedical Research Institute release 6 August 2002 You've trained for years for the ride of a lifetime, been chosen to serve in an elite corps, trained even more right up until launch, and what happens during your first couple of days in orbit? You're sick! Space motion sickness symptoms are similar to motion sickness on Earth. About 70 percent of first-time space travelers develop the condition during the first few hours in space with symptoms peaking around 10 hours into the flight. The condition can recur when returning to Earth's gravity, which, along with takeoff, is one of many critical events during space flight. The medications currently available affect a person's cognitive ability. "Astronauts typically take promethazine, a medication used to treat nausea. It's a good medicine, but it causes sedation," said Dr. John L. Dornhoffer, a researcher on the National Space Biomedical Research Institute's (NSBRI) neurovestibular adaptation team. "Astronauts have worked all their lives to do this job, and they want to avoid taking something that makes them sleepy." The drugs can impair the ability to react quickly, think clearly and recall information, so spacewalks are out of the question. And, extravehicular activity is never an option when a crewmember feels nauseous. An ear, nose and throat specialist, Dornhoffer is researching four drugs--lorazepam, meclizine, promethazine and scopolamine--to determine what drug is most effective at reducing space motion sickness without impacting cognitive and physical ability. His team is also researching the most effective way to administer the medications. "These drugs are used to treat balance disorders, and all have central nervous system side effects. We are using cognitive tests to determine which medication causes the least impairment," said Dornhoffer, associate professor of otolaryngology at the University of Arkansas for Medical Sciences and executive director of the Prosper Meniere Society. Seventy-five healthy study participants are undergoing different tests to overstimulate the inner ear, creating symptoms of vertigo, similar to what may be felt in space. Vertigo sufferers often feel their surroundings are moving or they are spinning around and cannot get their bearings. Others feel like they are being pulled toward the floor or to one side of the room. Other than nausea and vomiting, symptoms include difficulty focusing, sweatiness and heart palpitations. A rotating chair spins subjects starting at five revolutions per minute (rpm). The speed is increased by two rpm every five minutes until a total of 30 rpm is achieved in an hour. While spinning, participants are cued to make head movements that create significant stimulation of the inner ear. "A healthy individual can do that for about 15-25 minutes before feeling sick. The subject then does the test a second time after taking a drug countermeasure or placebo to test the response," Dornhoffer explained. An Operant Test Battery, developed by a co-investigator at the National Center for Toxicological Research, is being used to measure cognitive impairment as a result of drug administration and induced vertigo. The test measures specific tasks including time perception, short-term memory and learning. A custom-designed off-axis rotating chair, located at the University Hospital in Antwerp, Belgium, is being used to validate the rotating chair results. By spinning subjects off axis, the inner ear's otolith organ is stimulated and then analyzed. The otolith is the inner ear's gravity-sensing organ. While in the chair, subjects wear a three-dimensional eye-tracking device, which measures horizontal, vertical and rotational eye movements. This combination of devices allows the inner ear's three semicircular canals to be studied separately. Once the testing is completed and the data analyzed, the group will test the best way to administer the drug or drug combination. The study results will have benefits to patients on Earth suffering from balance disorders such as vertigo, disequilibrium or Meniere's disease. The rotating chair model is already being used to test patients on Earth suffering from undiagnosed balance problems. The NSBRI's consortium members include Baylor College of Medicine, Brookhaven National Laboratory, Harvard Medical School, The Johns Hopkins University, Massachusetts Institute of Technology, Morehouse School of Medicine, Mount Sinai School of Medicine, Rice University, Texas A&M University, University of Arkansas for Medical Sciences, University of Pennsylvania Health System and University of Washington. The NSBRI is funded by NASA. Contact: Liesl Owens Phone: 713-798-5893 E-mail: info@www.nsbri.org _____________________________________________________________________ JUPITER UNCLOAKS: MOST MOONS EVER FOUND AT ONCE From Astrobiology Magazine 7 August 2002 Jupiter's outer, irregular satellite system has long confounded predictions of what a moon should be. Fascinated particularly by the probable water-ice oceans on one of the six inner Jovian moons-- Europa--moon-hunters and astrobiologists alike have begun employing some novel search strategies for even more exotic ones than Europa. Previously, the scientists who classify known natural satellites have had 100 candidates to probe in our solar system. But with the latest observing tools, now the number of moons is climbing rapidly. Jupiter alone remains the primary parent body to an astonishing 39 moons thanks to a recent University of Hawaii sky survey. In May of this year, a team headed by Hawaii astronomers Scott Sheppard and David Jewitt confirmed the largest number of satellites ever discovered at one time--eleven. The eleven, including one previously found but long-lost to view since 1975, now make up part of the outer irregular Jovian satellite system. Until just the last 400 years, only the Earth had an observable natural satellite. But with Galileo's first crude telescope, astronomers looked with initial success to the Giant Planet, what might have first seemed to them as just a bright star. Jupiter first uncloaked its four biggest moons, now called the Galilean system or inner Jovian satellites. Since Galileo, nearly ten times more Jovian moons total have been discovered. One-hour photo To find their tiny moons, Sheppard and Jewitt peered through a telescope larger than Galileo himself. The mammoth 7 foot lens (88 inch, 2.2 m) sits majestically atop the remote 13,800 foot Mauna Kea volcano. Prospective moon-hunters wanting to use the Mauna Kea telescopes climb high enough to require a day to acclimatize at Hale Pohaku for one night before starting a new observing run. Compared to that first Galilean telescope that probed Jupiter, the tools are not only enormous but also [more] precise. Even while the world's largest observing domes of the nearby main Keck facility stand eight stories tall and weigh 300 tons, they operate with nanometer precision and move to instrument settings measured in units 10,000 times smaller than a human hair. All 11 moons were discovered using the so-called "8K" camera at Mauna Kea and are unusual additions to the neighboring astronomical zoo. The photographic signature or permanent record of the night sky is analyzed after the night's observation run to pinpoint candidate moons conveniently using computers. This astronomer's dream, the 8k CCD camera, was built at Hawaii's Institute for Astronomy by Gerry Luppino and is one of the world's largest astronomical cameras. When first found from a series of 3 photographic panels or plates (typically taken about a half-hour apart), the visible objects that move against the relatively stationary star and galaxy background make the initial candidate list. But since asteroids between the Earth and Jupiter can also move against the galactic background, Sheppard and Jewitt could only be sure of their discoveries by honing in on the characteristic slower speeds that might demark an orbiting object. Small, fast and dark, their sizes vary between 3 and 8 km (2-5 miles) across. They're also a long ways from Jupiter itself. Their orbits are large, eccentric and inclined steeply to Jupiter's equator. The farthest 9 of them orbit a path nearly 300 times bigger than Jupiter itself, compared to the more modest Earth-Moon ratio of about 60:1 and a lunar orbit that more closely mimics the innermost Jovian satellite Io, at 380,000 km. In total the farthest new moon discovered orbits at a colossal distance more than 40 million kilometers away from Jupiter, but makes the orbital round trip once every one to two years. How Jupiter became the king What is completely unknown about such irregular satellites is how they come to exist at all. When Jupiter was young, it is thought, many asteroids (or dynamical clusters) orbitted the Sun. As Jupiter condensed, its gravity began to bend the paths or even capture some of these stray asteroids. The best evidence for such a capture hypothesis is that many of these new satellites actually orbit in a direction opposite to the rotation of Jupiter, or otherwise follow what is known as retrograde orbits. Nine of the new Jovian moons are retrograde and join with the previous 5 known examples to yield 14 total. But while the capture theory can explain the backwards orbits, that finding alone is only half the story of how actually to hold on to them once caught. The problem arises in slowing down the moon to a stable orbit. Following a large solar orbit requires lots of speed and energy, while going against the flow of Jupiter--if captured--is likely the only way to dissipate all that escape energy. At least for Jupiter in its present state, capture is almost impossible. As Jewitt noted, "The origin of the dissipation that lead to the capture of Jupiter's irregular satellites is unknown. In fact, at the present time there is no plausible source of dissipation so that capturing satellites is presently almost impossible." Only if Jupiter's atmosphere extended well out into the capture zone, could friction start to slow down the moons and keep them from flying off or back into solar orbit. A much bloated Jupiter, and its atmospheric drag, could spawn such unusual tiny moons: captured into a backwards orbit, spanning vast relative distances but held just tightly enough to keep them as part of the 39 or more such moons. The best evidence for this theory appears to be the distinct families of moons that orbit at the same inclination to Jupiter's equator as a kind of dynamic cluster that might have broken on capture. Indeed the Giant Planet has many characteristics of a mini-solar-system unto itself. What's next Most critical to astrobiologists studying Jupiter's moons, the eccentricity or oval shaped orbits of Jupiter's moons are pumped or oscillated by tidal forces as they orbit. This input of Jupiter's gravitational energy heats up the inner moons particularly without relying only on the Sun's radiant heat, and thus gives an interesting way to provide one of the three ingredients for life--an energy source--even if far from the Sun. What remains to be found among the Giant Planets like Jupiter and Saturn are some candidates that combine all three ingredients for primitive life: energy, liquid water and some atmosphere. Only Saturn's moon, Titan, has an appreciable atmosphere, and only Jupiter's Europa or Ganymede have any indications of water ice. But uniquely powerful tidal forces around the Giant Planets do offer some promising, non-radiant and non-volcanic heat sources. Collaborators on the eleven Jovian moons and its related sky survey included Scott Sheppard, David Jewitt, Yan Fernandez and Gene Magnier. Additional information on this article is available at http://www.astrobio.net/news/article247.html. _____________________________________________________________________ ONE SMALL STEP... BUT ONLY ON A HOSPITABLE PLANET! From ESA Science News http://sci.esa.int 8 August 2002 Around the world, there is renewed interest in sending a manned mission to other planets in our Solar System. What conditions await future astronauts? Space science provides many clues. Before leaving Earth, scientists want to use robotic spacecraft to find out more about the conditions that human travellers will face once they reach some far-off destination. A flotilla of planetary exploration missions is already providing us with invaluable scientific data about other worlds. Stepping onto other planets to perform scientific investigations yourself is an old dream. However, most science done today uses robotic missions. Huge distances in space, harsh environmental conditions, and the status of current technology put strong limitations on the human exploration of space. Of the nine planets in our Solar System, Earth is the only one that is "habitable", meaning that human beings can breathe the atmosphere and move around in reasonable temperatures. Of the other planets, the best we can hope for is that they are "hospitable". None of them possesses the special mixture of gases that make up the Earth's air, nor its mild temperature. The giant planets of the outer Solar System--Jupiter, Saturn, Uranus, and Neptune are all gaseous. Lacking solid surfaces, they have clouds all the way down to their deep, compacted cores. Although they all have moons on which you could land, these are too far away to be within the current reach of astronauts. The nearest planet to Earth is Venus, but this world is a boiling mixture of noxious gases with a surface temperature hotter than a kitchen oven and a pressure 600 times higher than on Earth. The planet Mercury is too close to the Sun. So neither Venus nor Mercury are "hospitable" by human standards. That leaves Mars and the Moon. Both are hospitable, with temperature ranges that are bearable and an atmosphere that is absent in the case of the Moon and not too corrosive in the case of Mars. Astronauts with proper spacesuits would be able to get by in these conditions. Both the Moon and Mars are also relatively close by to Earth, requiring journey times of less than a year: in the case of the Moon, about three days, for Mars, about nine months. Apart from these large worlds, there are also a number of smaller destinations within reach. For example, there are very many so-called near-Earth asteroids that are the leftovers of planet formation. Going there may reveal clues to how the Earth and other planets formed. Current scientific missions to other worlds in the Solar System are not only important for their absolute scientific value, but also because the information we gather prepares us for future visits by human beings. Astronauts will have to endure many hardships living and working in these places. For example, there are gravity differences compared to Earth, the lack of atmosphere to shield them from harmful solar radiation and, on Mars, the tremendous dust storms that regularly engulf the planet. Understanding as much as possible about these places is essential before we launch any human missions. ESA's current planetary missions are perfect starting points to learn about new worlds. For example, Mars Express and SMART-1 will provide vital data about the presence and the distribution of water and ice on Mars and the Moon, respectively. Another mission, Rosetta, will even drop a lander on a comet. The experience we gain with Rosetta will be invaluable for us to perfect techniques to land on near-Earth asteroids in the future. Other projects such as Mars Express, Venus Express, BepiColombo, which will go to Mercury, and Huygens, which will go to Titan, will play their part in refining environmental measurements on other worlds also. In 2001, ESA began preparing the Aurora program, Europe's bold roadmap towards the eventual human exploration of the Solar System. While the purely scientific investigation of the Solar System continues, ESA's newest exploration program, Aurora, will add another dimension. It will launch a number of robotic missions focused on clarifying those scientific aspects that we need to understand to make human exploration possible. Useful links for this story * More about SMART-1 http://sci.esa.int/smart * More about Mars Express http://sci.esa.int/marsexpress * More about Rosetta http://sci.esa.int/rosetta/ * More about Aurora http://spdext.estec.esa.nl/content/doc/9f/30367_.htm [http://sci.esa.int/content/searchimage/searchresult.cfm?aid=1&cid=12 &oid=30357&ooid=17956] SMART-1 on the way to the Moon. [http://sci.esa.int/content/searchimage/searchresult.cfm?aid=1&cid=12 &oid=30357&ooid=13294] ESA's Mars Express mission, scheduled for launch in 2003. [http://sci.esa.int/content/searchimage/searchresult.cfm?aid=1&cid=12 &oid=30357&ooid=30188] Rosetta will drop a lander on a comet. This artist's impression shows Rosetta, its lander, and Comet Wirtanen. An additional article on this subject is available at http://spaceflightnow.com/news/n0208/10step/. _____________________________________________________________________ TO DISTILL SOME WATER By Trudy E. Bell and Tony Phillips Adapted from a story by Jack London 9 August 2002 This fact-filled science fiction tale, based on Jack London's "To Build a Fire," describes an astronaut's urgent search for something to drink on Mars. Day had broken, cold and reddish, exceedingly cold and reddish from dust suspended in Mars's thin atmosphere, when the explorer climbed the inner crater wall. It was a steep wall and even in four-tenths Earth gravity his spacesuit was cumbersome. No wonder he slipped. Feet scrambling, the suited figure fell and tumbled. He came to rest just a few meters downslope--a short fall, but the damage was done. He heard it: something crunched. Inside the suit the man took a cautious breath; everything seemed fine. Probably just two rocks rubbing together, he thought, struggling upright. Moments later he was at the top. From there he could see the 2020 Mars Expedition's six-person living quarters and experimental water-extraction plant. They looked small and fragile below on the vast crater floor. A few hundred kilometers north, hidden beyond the sharp curve of Mars's nearby horizon, was a polar ice cap--three kilometers thick and full of dusty, frozen water. But the explorer, a hydrologist, was bound only for a few nearby hillocks to dig soil samples. He planned to test just how water-rich this area was for supporting a possible full-scale permanent colony. The camp commander--a biologist--had warned him: no scientist should travel alone outside the crater's wall. Mission rules required a "buddy." But he wasn't going all that far, he thought. He descended the crater's outer wall in slow bounds. At his heels trundled a waist-high robotic rover. "The Husky" they called it--a proper dune buggy with springy wire wheels and treads, laden with several latched titanium boxes, a supply bag, and what looked like a miniature distillery. Once in a while on the downward slope, the explorer skidded a bit on loose gravel and kicked up puffs of talcum-fine reddish dust that remained suspended for minutes in the thin martian air. It clung to everything. It sure would be nicer to ride, he thought, as he rubbed the dust off his faceplate. But in 2010, NASA engineers had calculated that precious expedition weight could be saved if most rovers were built only large enough to haul equipment and not passengers. Short journeys were done on foot. At half-past 12 to the minute, Martian time, he arrived at a hillock crisscrossed with a network of small, dry rivulets meandering away down its north side. The rover's on-board neutron spectrometer was beeping: it had picked up a massive concentration of hydrogen-- probably water-ice--not far beneath his feet. He was pleased at the speed he had made. At this rate, he should be able to get samples from several hillocks and return to camp by six, where a hot supper would be waiting. Thirsty from his vigorous hike, he sipped at his spacesuit's water supply. It gurgled like a soda straw drawing up the last of a milkshake from the bottom of a glass. Puzzled, he tried again. He had filled it that very morning--it ought to work. Then he remembered. That crunching sound back at the crater, it must have been his water bottle. He reached around and unscrewed the cylinder. It was cracked... and empty. The explorer cursed his luck. Here he was; he had had an accident; and he was alone. That biologist back at camp was right after all. And he was sure to hear about it for the next two years. He licked his dry lips. Even in a spacesuit, dehydration was an ever-present threat in the thin, desiccated arctic air of Mars. Thinking about it made him thirstier. Work the problem, he reminded himself. He reached into the Husky's supply bag and pulled out a small roll of duct tape--not standard issue, but no one left camp without one. Moments later the bottle was water-tight again. It was still empty, though, and he needed to refill it. But how? He glanced down, and only his helmet stopped him from slapping his forehead. Of course! What he needed was right there, underfoot. He activated the rover's drill, which looked like a miniature post hole digger, and started drilling into the reddish soil. The first 20 centimeters went quickly--it had the loosely cemented texture of powdery sand that had once been wetted and then dried. Half a meter deep, however, the drill slowed as it encountered layers as dense as clay. The explorer pulled out the drill and knelt to examine the hole. Mars dirt looked nothing like the permafrost layers of tundra in Earth's living Arctic where ice gleamed as distinct crystals within the soil. What he saw here reminded him more of compacted volcanic ash. (He had run his bare hand across some once on the slopes of Iceland's primitive basaltic volcano Mount Hekla. On Mars, he dared not remove his glove.) It looked awfully dry. Even so, its sorbet-fine crunchy texture suggested it was maybe 40 to 50 percent ice by volume. Good thing, the explorer thought--he had never experienced such thirst. And, besides, he didn't want to admit defeat. Carefully, he dumped the dense sample into the rover's gas-analyzer oven, where it was hermetically sealed and pressurized. The chamber looked pitifully small--after all it was intended only for scientific analysis. But he hoped it would yield at least enough water to alleviate his growing thirst. The oven's plutonium-fueled heater gave out 100 watts of continuous power. Setting it to slow melt would create a muddy slurry, useless for drinking. So he set it to stepwise heating--to flash the soil's temperature to 200°C, immediately vaporizing any ice. Through a small window, he watched as delicious droplets condensed on cooling plates and rolled into a sample-collection cup. Mouth parched, he cherished the sight. He paused. Was this distilled water even safe to drink? What minerals might still be dissolved in it? Were there even, perhaps, martian organisms? Back at camp were all the Expedition's apparatus for testing and sterilization--and even then they didn't use Mars water for drinking. But the sight of the filling cup put a wild idea into his head. I just won't swallow, he thought. Or maybe I'll be the first to drink Mars water. He unlocked the oven's external door, retrieved the cup, and moved to drain it into his suit's water bottle. But not fast enough. The water began fizzing and steaming angrily, leaping over the rim and then freezing in a tiny cloud of ice crystals. In moments, the cup was completely dry. He struggled for calm. Liquid water was highly unstable in Mars' vacuum-like atmosphere. He knew that, but he didn't realize how rapidly it would boil. Could he make it back with no water? He glanced around at the alien terrain and felt a little scared. It struck him that he should radio for help to see if someone could meet him with extra water halfway. "You were right, you were right," the explorer mumbled as he flipped the switch. Sure enough, it was the biologist who answered. End note: Current knowledge about the approximate nature of ice-laden martian soils and the operation of the stepwise gas-analyzer oven was provided by Dr. James Garvin, lead Scientist for Mars exploration at NASA Headquarters, based on results from Mars Odyssey and previous spacecraft. The fictional explorer, of course, is a 21st-century reincarnation of the nameless pig-headed miner in Jack London's famous 1908 short story "To Build a Fire," while the freight rover is an adaptation of the man's husky. Additional information on this article is available at http://science.nasa.gov/headlines/y2002/09aug_marstale.htm?list52260. _____________________________________________________________________ TRADITIONAL CHINESE MEDICAL HERBS GET BOOST FROM SPACE TRAVEL From SpaceDaily and Agence France-Presse 11 August 2002 Traditional Chinese medical herbs that have been on a trip to space grow larger and more resistant than their earth-bound relatives, state media said Sunday. Researchers at the Kewei Space Plant Propagation Base in northern Hebei province reached that conclusion after monitoring the growth of herbs from seeds that had traveled in space, Xinhua news agency said. "The space plants have larger leaves and stronger stems and are more resistant to insect pests," said Chen Miaozeng, a scientist at the base. Get the full story at http://spacedaily.com/news/020811040559.wvcr1c8l.html. _____________________________________________________________________ WEIRD LIFE ON THE MATS By Lee J. Siegel From Astrobiology Magazine 12 August 2002 More than a half-billion years ago, as early animal life began evolving and diversifying in the oceans, some strange-looking seafloor critters became scarce or went extinct. The conventional view has been that they represented failed evolutionary experiments-- unfit dead ends on life's inexorable path to greater complexity. David Bottjer, however, offers a different interpretation. The University of Southern California earth sciences professor says the now-extinct animals were well-adapted to their Precambrian environment. They lived atop microbial mats, which were firm yet slimy layers of archaeans, bacteria and other single-celled microorganisms that covered the seafloor like scum on week-old pudding. Then, during the Cambrian, a period of about 40 million years that began some 543 million years ago, the environment changed. Worms, early beetle-shaped multi-legged arthropods known as trilobites, and other "bioturbators" evolved and started churning up the seafloor and destroying microbial mats, turning the once-firm seabed into soft, mucky sediment. Some animal species that lived on microbial mats went extinct; others persisted in limited areas where mats survived; and yet others evolved into new forms able to thrive atop rocks or shells. Bottjer calls these changes in the seafloor sediment ecosystem "the Cambrian substrate revolution," and compares what trilobites and worms did to the ocean floor to the radical agricultural change wrought by human settlers who spread across the American Great Plains in the 1800s. "You think of it like settlers sod-busting the prairie," he said. "They changed soil properties tremendously." Bottjer says that if many early animals or metazoans look strange to us today, it is not because they were strange, but because they were well-adapted to life on a strange ocean seafloor environment: the microbial mat ecosystem. He notes that to modern people, early motorists look odd, wearing dusters and riding in automobiles with tall wheels. "Yet the unusual clothes and wheels were just adaptations to a mushy road surface--dirt roads. Today everybody drives on paved roads a hard surface. Cars can drive low to the road and we have enclosed cabs and don't have to wear special clothing." While dirt roads gave way to pavement, Bottjer says the opposite happened to the Cambrian seafloor: relatively firm, mat-covered sediments were replaced by soft, mushy seafloors. "Today, microbial mats typically are found only in shallow near- shoreline environments where you have [inflowing] freshwater, or where evaporation creates more or less salt than normal seawater. That keeps out the snails and other organisms that chew on and destroy these mats." In a published study and presentations over the past two years, Bottjer and colleagues have described how the change from firm to mushy seafloor affected two categories of animals: early echinoderms, which later evolved into today's sand dollars, sea urchins, starfish and sea cucumbers; and early mollusks, which Bottjer says later evolved into "things you find at your seafood restaurant: squid, snails, clams, oysters, scallops." The radical change in the seafloor environment caused the extinction of echinoderms known as helicoplacoids, which were plate-covered organisms shaped like tops and the size of a human thumb. Helicoplacoids stuck atop microbial mats while filtering microscopic nutrients from ocean water. Bottjer says helicoplacoids were like "big trees that needed to have a stable surface to sit on." But once seafloor mats were replaced by muck, helicoplacoids probably were unable to live on the unstable sediment. "They only survived for maybe 10 million years after the beginning of the Cambrian. They never were seen again." Two other types of echinoderms adapted to the change by finding other firm footing. Cupcake-shaped edrioasteroids also filtered seawater for food, but by the late Cambrian, the only known edrioasteroid fossils "were sitting on a shell or rock," Bottjer says. Weird, peanut-shaped eocrinoids, which used arm-like appendages to collect food from water, "evolved a stem. It allowed them to attach to hard surfaces like rocks or shells. They moved up onto these surfaces which projected above the soft sediment." Several early mollusks also were restricted to life on rocks and other firm surfaces when seafloor mats were churned up. For example, the ancestors of mollusks such as polyplacophorans (or chitons), lacked shells, so "the earliest ones probably looked like slugs crawling across the mat-covered seafloor," Bottjer says. These several-centimeter-long creatures left scratch marks on microbial mat fossils, indicating "these guys were munching on the mat like the snail does [to algae growing on glass walls] in your fish tank. They were grazing on their environment, but they were not destroying it." Other mollusks, known as monoplacophorans, typically were shaped "like a baseball cap without the bill" and measured up to several centimeters wide, says Bottjer. "They used to be all over the shallow seafloor [until mats were wiped out], but now they are stuck in deeper-water environments living on rocks and other firm surfaces." Bottjer believes the Cambrian change in the seafloor also caused the extinction of certain lobopods, which looked like worms but moved around with foot-like pods projecting underneath them. Their modern relatives, called velvet worms, live in forest litter. Bottjer says one of the first lobopods discovered had spines and was named Hallucigenia "because it looked pretty darn weird." It may have walked on microbial mats, but went extinct when the seafloor turned mucky. Bottjer says understanding odd early animal life on Earth is important for astrobiology because life on other planets might look strange to us, but might be perfectly well-adapted. It also is conceivable that if any animals evolved in Mars' now-vanished oceans, maybe they would be adapted to microbial mat surfaces and look more like Cambrian things than modern-day organisms" on Earth, he says. Other scientists agree with Bottjer that the seafloor changed at the dawn of the Cambrian, but they say it will be hard to prove how that affected early animal life. "The basic substrate revolution story is correct in that you see it in the rocks," says Bruce Runnegar, a paleontology professor at the University of California, Los Angeles. "But I'm not sure about what he speculates about the behavior of animals in the Cambrian. This is a nice story. But how would you find out if it was true?" Runnegar notes that many early animals had soft bodies not likely to be preserved, and that their limited fossils do not necessarily reveal how the creatures lived. While impressions of some soft- bodied early animals can be found where mat materials preserve sediment layers, it is difficult to know if such organisms later went extinct or simply were not preserved after mats were destroyed. Runnegar notes fossil preservation "is something we need to know more about if we're going to search for life on other planets." "The difficulty with Dave's idea [on how early animals were affected by the change in seafloor sediments] is that while it may be correct, it is awfully difficult to test given the nature of the fossil record in the Cambrian," says paleobiologist Doug Erwin, interim director of the National Museum of Natural History in Washington. "Reconstructing ecological interactions is one of the great challenges of paleobiology," Erwin says, "while a major challenge for astrobiology is to learn: Did the origin of a new group correlate to some physical change in the environment?" He says that "if life is found on other planets, the next question is: How has the history of that planet influenced the history of life on that planet? The place we have to start answering it is on this planet. We have a lot more data here than we're ever going to have from Mars." What's next? Bottjer wants to compare China's early Cambrian Chengjiang site with Canada's middle Cambrian Burgess shale for more evidence of "how Cambrian organisms adapted to changing seafloor conditions through time." Bottjer and USC doctoral student Steve Dornbos have made several trips to southwest China to study the Chengjiang fauna, in conjunction with Junyuan Chen of the Nanjing Institute of Geology and Paleontology, and more studies are planned, particularly on sponges and relatives of corals from the Cambrian. Bottjer and Dornbos were joined in their Cambrian substrate research by James Hagadorn, a former USC graduate student who recently joined the faculty at Amherst College in Massachusetts. Additional information on this article is available at http://www.astrobio.net/news/article251.html. _____________________________________________________________________ NEW ADDITIONS TO THE ASTROBIOLOGY INDEX By David J. Thomas http://www.lyon.edu/webdata/users/dthomas/astrobiology/astrobiology.h tml 13 August 2002 Astrobiology, exobiology and terraformation articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_article s1.html M. N. Mautner, 2002. Planetary bioresources and astroecology. 1. Planetary microcosm bioassays of martian and carbonaceous chondrite materials: nutrients, electrolyte solutions, and algal and plant responses. Icarus, 158:72-86. R. Stendger, 2002. Europe begins building Mars lander. CNN. Human space exploration and microgravity effects articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_article s3.html Agence France-Presse, 2002. Traditional Chinese medical herbs get boost from space travel. SpaceDaily. T. E. Bell and T. Phillips, 2002. To distill some water. NASA Science News. Evolutionary biology and chemistry articles http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_article s5.html NASA Jet Propulsion Laboratory, 2002. Stardust spacecraft reaches for cosmic dust. Spaceflight Now. L. J. Siegel, 2002. Weird life on the mats. Astrobiology Magazine. Astrobiology and extreme environments book list http://www.lyon.edu/webdata/users/dthomas/astrobiology/astrobiology_b ooks.htm L. Margulis and M. F. Dolan, 2002. Early Life: Evolution on the Precambrian Earth, 2nd Edition. Jones and Bartlett Publishers, Boston. M. N. Mautner, 2000. The Purpose and Future of Life: The Ethics and Science of Seeding the Universe. Legacy Books. C. Zimmer, 2001. Evolution: The Triumph of an Idea. Harper-Collins, New York. _____________________________________________________________________ CASSINI SIGNIFICANT EVENTS NASA/JPL release 1-7 August 2002 The most recent spacecraft telemetry was acquired from the Goldstone tracking station on Tuesday, August 6. 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 this week included an autonomous Solid State Recorder memory load partition repair, clearing of the ACS high water marks, calibrations of the Radio and Plasma Wave Science High Frequency Receiver, and RADAR periodic instrument maintenance. Science Planning reported completion of the third and final input port products for Science Operations Plan development of the S09/S10 tour sequences. The sequences will be completed in two weeks. In addition, a kick-off meeting was held for the Science Planning Team process for C35. The Navigation Team has analyzed radiometric data gathered during the solar conjunction that has been conditioned by a technique developed by the Cassini Radio Science Team. The results are very positive. Typically, media noise during solar conjunction corrupts the ranging and Doppler data to such an extent that the data sets are unusable. However, by using the Ka band signal received during the recent solar conjunction experiment, members of the Radio Science Team were able to remove the media effects from the X-band signal with remarkable success. This capability will have little effect on Cassini's interplanetary navigation, but could be a significant help for orbit estimation during the tour phase. Topics at this week's Mission Planning Forum included a presentation by the Navigation team of their findings on the impact of moving Orbit Trim Maneuver -11, a deterministic maneuver near Saturn periapsis, to accommodate Satellite Orbiter Science Team science, and the possibilities for conducting a Titan dress rehearsal for the RADAR instrument prior to Saturn Orbit Insertion. Members of the Uplink Operations Team traveled to the University of Arizona to give a demonstration of the Science Opportunity Analyzer tool to Visual and Infrared Mapping Spectrometer (VIMS) instrument personnel. VIMS has volunteered to do an evaluation of the tool to assist in determining what additional resources should be invested in further development. The Spacecraft Office held a Monthly Management Review of CDS and ACS flight software, SOI and probe relay critical sequence development, and the Integrated Test Laboratory. These activities are on schedule and have no significant problems. Several Cassini teams and offices supported the NASA Quarterly review on Monday, August 5. Cassini Formal Education, a part of Cassini's Outreach program, conducted a workshop designed to build two Reading and Language Arts units focusing on Saturn and the Cassini Mission. The workshop involved six elementary school teachers, the Bay Area Writing Project, Project FIRST, JPL, and the Caltech Pre-College Science Initiative. Continued engagement with the K-4 community has been made more difficult by the imposition of standardized testing in language. Pressure is being exerted on teachers to eliminate the teaching of science in K-4 in favor of more time for language instruction. The current materials that teachers are given from publishers deal mostly with fiction based reading and writing. Non- fiction, expository reading and writing using the science from the Cassini mission will help fill this curricular gap. 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. _____________________________________________________________________ THE NEXT FOUR WEEKS ON GALILEO NASA/JPL release 12 August - 8 September 2002 As the Galileo spacecraft continues its long trek back in towards Jupiter for its final planned science pass in November, the pace of activity picks up. In addition to the routine maintenance activities that look after spacecraft health and safety, special tests are beginning in preparation for the Amalthea flyby. On Thursday, August 15, the spacecraft will perform a test of an attitude maintenance strategy being considered for the upcoming flyby. Normally, when Galileo is in close to Jupiter, the high radiation environment creates enough noise in the star scanner electronics to mask the signals from all but the very brightest stars. For a typical flyby of the innermost of the four large satellites, Io, one single bright star can still be reliably detected, and the spacecraft maintains its attitude knowledge using an on-board software routine called One Star Attitude Determination. Frequently during such a flyby, however, a large body such as Io temporarily blocks that single star from view, and the one-star routine must be configured to go into "hibernation", expecting to see no stars at all for a period of perhaps 15 minutes. For the November flyby, Galileo is going to pass much closer to Jupiter than it has ever done before. The increase in radiation at this closer distance will cause even the brightest star in the sky to disappear into the electronic noise for a period of up to nine hours! The hibernation test we will perform this week will tell us how the spacecraft systems respond to being told to ignore the sky altogether for extended periods of time. On Monday, August 19, Galileo closes the distance to Jupiter to a mere 300 Jupiter radii (21.4 million kilometers or 13.3 million miles). Though 3.5 million kilometers closer than its farthest reach during this orbit, we are still farther from Jupiter than we have been since before entering orbit in December of 1995. The spacecraft is still well outside the magnetosphere of Jupiter on the sunward side of the planet, and continuous data collection by the Magnetometer, the Dust Detector, and the Extreme Ultraviolet Spectrometer instruments provides scientists with information about the interplanetary medium. On Tuesday, August 20, and again on Saturday, September 7, the spacecraft will turn in place approximately 4 degrees to keep the communications antenna pointed towards Earth. On Wednesday, August 21, routine maintenance of the propulsion system is performed. On Sunday, September 1, the Near Infrared Mapping Spectrometer team collects some engineering data from the instrument to assist in the final calibration of the response of the instrument. These data will aid in the interpretation of the final set of science calibration data collected from the instrument in March of this year. On Friday, August 16, the next series of tape recorder tests will begin. This is the last test that will exclusively use the recorder's slowest speed. This test moves back and forth the full length of the tape without stopping. This action repeats 10 times, for 20 full passes over the tape. Another test begins on Saturday, August 24, when we switch gears to use a faster tape speed. This tape speed is about 13 times faster than the slowest speed, and is the fastest we plan to use the recorder during the final flyby. This first high-speed test travels back and forth the length of the tape in 6 hops per track. On Monday, September 2, the next high-speed test begins that travels the length of the tape in only 2 hops. The data that we are receiving from the current set of tape tests indicate that the tape is still somewhat sticky. We are still able to reliably move the tape, however, and we believe that by exercising the recorder nearly continuously between now and November, we can reduce the stickiness and keep the tape moving freely. This will enable us to successfully record the magnetospheric data as planned as we plunge through the depths of the Jovian radiation field in November. 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 _____________________________________________________________________ INTERNATIONAL SPACE STATION SCIENCE OPERATIONS STATUS REPORT NASA/MSFC release 02-199 7 August 2002 The Solidification Using Baffle in Sealed Ampoules (SUBSA) science team was scheduled today (August 7) to begin their fourth experiment run of Expedition Five aboard the International Space Station. The sample will be removed on Thursday for storage until it can be returned to Earth. The Space Station crew and controllers successfully completed their third test run last Friday, August 2, following troubleshooting tests and uplink to the Station of a software patch to increase the SUBSA furnace temperature. Approximately 2 millimeters of the semiconductor "seed" material was melted before the sample was allowed to cool and crystallize. The furnace temperature required to melt back 2 mm in this experiment was 831 Celsius. It was the experiment team's first sample run using a disc-shaped baffle to minimize microgravity-induced motion in the melted material. The results will be compared to those experiments without a baffle. "We had a good video of the process and everything went perfect," said Dr. Aleksandar Ostrogorsky, of Renssalaer Polytechnic Institute in Troy, New York, principal investigator for the experiment. "We did not see any bubbles, which are undesirable, or de-wetting. The growth rate was 5.4 millimeters per hour, also close to perfect. It appears now that our equipment is fully tested and is functioning well. We do not expect any difficulties in processing the remaining SUBSA ampoules." SUBSA is investigating the distribution of impurities in a semiconductor crystal during processing. The goal is to identify what causes the motion in melts processed inside space laboratories and to reduce the magnitude of the melt motion so that it does not interfere with the distribution of impurities. These impurities, or dopants, are used to control the opto-electronic properties of the crystals, and uniform distribution of the dopant is essential to achieve the desired opto-electronic properties. Commander Valery Korzun and Flight Engineers Peggy Whitson and Sergei Treschev throughout the week collected and recorded their information for the Renal Stone experiment. Space crews have an increased risk of developing kidney stones during and immediately after flight. In- flight changes previously observed include decreased urine volume and increased urinary excretion of calcium, phosphate, and sodium. Beginning three days before launch and continuing through14 days after their return, Station crew members will ingest two potassium citrate pills or placebos daily with the last meal of the day. They will collect urine over 24-hour periods before, during and after flight as well as track food, fluid, exercise and medications before and during the urine collection period in order to assess environmental influences other than microgravity. Potassium citrate is a proven Earth-based therapy to minimize calcium-containing kidney stones. Kidney stone formation could potentially cause a mission to be ended early. Understanding how the disease may form in otherwise healthy crewmembers under varying environmental conditions also may provide insight into stone-forming diseases on Earth. Crew Earth Observations photography subjects this week included: industrialized Southeastern Africa, fires and smoke plumes over Zimbabwe, Lake Poopo in South America, a dust storm off the coats of Algeria and Tunisia, and air quality over the Eastern Mediterranean. On Friday, Korzun and Whitson are scheduled to participate in the Pulmonary Function in Flight (PuFF) experiment. PuFF focuses on lung function both following EVA and inside the Space Station. Nitrogen bubbles can form in the bloodstream in the low-pressure environment of a spacesuit, and long-term exposure to the microgravity environment inside the Station could affect lung strength. Each PuFF session includes five lung function tests, which involve breathing only cabin air. The focus is on measuring changes in the evenness of gas exchange in the lungs, and on detecting changes in respiratory muscle strength. Scientists hope to find new ways to protect the health of space travelers in the years ahead, and to gain a better understanding of the effects of gravity on the lungs on Earth. The Payload Operations Center at NASA's Marshall Space Flight Center in Huntsville, AL, manages all science research experiment operations aboard the International Space Station. The center is also home for coordination of the mission-planning work of a variety of international sources, all science payload deliveries and retrieval, and payload training and payload safety programs for the Station crew and all ground personnel. Contact: Steve Roy Media Relations Department Phone: 256-544-0034 E-mail: Steve.Roy@msfc.nasa.gov _____________________________________________________________________ MARS GLOBAL SURVEYOR MARS ORBITER CAMERA (MOC) 2002 SOLAR CONJUNCTION SAMPLER NASA/JPL/MSSS release 8 August 2002 The Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) was turned off on July 31, 2002, and it will remain off until at least August 19, 2002. During this time, Mars is behind the Sun relative to Earth, and communication with the spacecraft is extremely limited (for several days, there will be no communication at all). MOC is off during this time because any images it might acquire could not be transmitted to Earth, and the twice-weekly targeting schedules can not be sent to the spacecraft. Solar Conjunction is the term used to describe the period when the Sun is between Earth and Mars--from the Earth, Mars appears to move towards, and eventually merge with, the Sun. Solar Conjunction comes around about every 25 months, the first solar conjunction for MGS occurred in May 1998, the second in June/July 2000, the third in August 2002. Each time, the MOC was turned off and safely returned to service after the conjunction period ended. With the MOC "on vacation," the MOC Operations Team can also take a short breather, having commanded over 125,000 images over the past 4+ years. However, "short" is the operative word, as in a few days the team will be hard at work preparing for the MOC turn-on later in the month. The pictures shown here [see link below] are examples of some of the things the MOC team has been seeing in the past few months leading up to Solar Conjunction, including continued monitoring of mid-latitude gullies, dust devils, and chance observations of unusual landforms. Images and additional information are available at http://www.msss.com/mars_images/moc/8_2002_releases/index.html. _____________________________________________________________________ MARS ODYSSEY THEMIS IMAGES NASA/JPL/ASU release 5-9 August 2002 Promethei Terra (Released 5 August 2002) http://themis.la.asu.edu/zoom-20020805a.html Libya Montes (Released 6 August 2002) http://themis.la.asu.edu/zoom-20020806a.html Dao Vallis (Released 7 August 2002 http://themis.la.asu.edu/zoom-20020807a.html Proctor Crater Dunes (Released 8 August 2002) http://themis.la.asu.edu/zoom-20020808a.html Meroe Patera (Released 9 August 2002) http://themis.la.asu.edu/zoom-20020809a.html All of the THEMIS images are archived at http://themis.la.asu.edu/latest.html. NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, DC. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena. _____________________________________________________________________ STARDUST SPACECRAFT REACHES FOR COSMIC DUST NASA/JPL release 6 August 2002 NASA's Stardust spacecraft, on a mission to collect and return the first samples from a comet, began yesterday to collect tiny specks of solid matter, called interstellar dust grains, that permeate the galaxy. "If you look at the Milky Way on a dark night you may see a black band stretching along the center. The band is interstellar dust blocking the light from distant stars. These are the particles that Stardust will be collecting," said Dr. Don Brownlee, an astronomy professor at the University of Washington, Seattle, and the principal investigator of the Stardust mission. This dust, passing through the solar system like a wind, is made of particles smaller than one-hundredth the width of a human hair. The particles are made of varying amounts of most of the elements in the periodic table. The Stardust mission will use its special formulation of aerogel, the world's lightest solid, to try to capture these small solid particles as the spacecraft travels in the same direction as the dust stream until December 9, 2002. "Stardust's tennis-racket-shaped particle collector has shoulder and wrist joints that will point one side of the aerogel collector material into the dust stream to collect interstellar dust," said Tom Duxbury, the project's manager at NASA's Jet Propulsion Laboratory, Pasadena, CA. "When Stardust encounters comet Wild 2 in early 2004, the reverse side of the collector will trap particles from the gas and dust escaping from the inside of the comet. When the dust samples return to Earth in 2006, we will extract and analyze the particles," The Stardust mission collects both ancient and young dust. Comets are made of interstellar particles that clumped together with ices more than 4.5 billion years ago. When the spacecraft flies past comet Wild 2, it will attempt to collect ancient dust samples stored for billions of years in, effectively, a deep freeze. The mission began yesterday collecting a younger type of stardust: the free-flowing interstellar dust that was produced by the current generation of stars. Comparing the ancient and newer types of dust may provide clues to the evolutionary changes in the galaxy and the composition of the early galaxy. This is the second and final time Stardust will collect these dust particles. It previously collected samples during a six-week period in 2000. Comet Wild 2 is a particularly good example of preserved interstellar dust because its path through space brings it no closer to the Sun than Mars' orbit, about 228 million kilometers (about 141 million miles) from the Sun. Before 1974, the closest Wild 2 came to the Sun was Jupiter, Brownlee said. NASA's Galileo and Ulysses spacecraft both detected a stream of dust particles flowing between stars and into the solar system. The particles did not come from the Sun, but from another direction that showed their origin was outside the solar system. Interstellar dust may have played a role in bringing the building blocks of life-- carbon and other organic materials--to the young Earth. Similarly, comet impacts may have also brought these elements to Earth. Brownlee expects to find a lot of carbon in the interstellar dust particles. "When Earth-like planets form, comets and interstellar grains may bring carbon and organic material," he said. The interstellar dust stream differs from the solar wind in that the solar wind is made of individual atoms, while the interstellar dust is made of small particles of rocks with complex compositions. Stardust, a part of NASA's Discovery Program of low-cost, highly focused science missions, was built by Lockheed Martin Astronautics and Operations, Denver, CO and is managed by JPL for NASA's Office of Space Science, Washington, DC. JPL is a division of the California Institute of Technology in Pasadena. More information on the Stardust mission is available at http://stardust.jpl.nasa.gov. Additional articles on this subject are available at: http://spacedaily.com/news/020807202646.b5tble6k.html http://spaceflightnow.com/news/n0208/07stardust/ [Includes NASA artist concept of Stardust in flight.] _____________________________________________________________________ STARDUST STATUS REPORT NASA/JPL release 9 August 2002 There were two Deep Space Network tracking passes during the past week and all subsystems are normal. The aerogel grid was successfully deployed, marking the start of the second interstellar dust collection period. In order to ensure that the aerogel grid is perpendicular to the interstellar dust stream, the grid was tilted 56 degrees from its normal fully deployed position. The grid will be moved gradually toward the normal position until it reaches the fully open position in November. The grid will remain deployed until mid- December. Both German Public Television and CNN broadcasted news stories on the beginning of dust collection. The critical event readiness review has been postponed until mid- September. The Stardust Education and Public Outreach team participated in the NASA Summer School Program hosted at Caltech and led the annual Solar System Educator Program training workshop at JPL. 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 29.