Marsbugs: The Electronic Astrobiology NewsletterVolume 11, Number 31, 9 August 2004

Editor/Publisher: David J. Thomas, Ph.D., Science Division, Lyon College, Batesville, Arkansas 72503-2317, USA. dthomas@lyon.edu

Marsbugs is published on a weekly to monthly basis as warranted by the number of articles and announcements. Copyright of this compilation exists with the editor, except for specific articles, in which instance copyright exists with the author/authors. Opinions expressed in this newsletter are those of the authors, and are not necessarily endorsed by the editor or by Lyon College. E-mail subscriptions are free, and may be obtained by contacting the editor. Information concerning the scope of this newsletter, subscription formats and availability of back-issues is available at http://www.lyon.edu/projects/marsbugs. The editor does not condone "spamming" of subscribers. Readers would appreciate it if others would not send unsolicited e-mail using the Marsbugs mailing lists. Persons who have information that may be of interest to subscribers of Marsbugs should send that information to the editor.

Articles and News

Page 1 CLIMATE CHANGE COULD DOOM ALASKA'S TUNDRABy David Stauth

Page 2 FLYING DINOSAUR NEEDED A BIRD'S BRAIN By Jeff Hecht

Page 2 ROCKING THE CRADLE OF LIFE—FINDING THE PREBIOTIC BOUNDARYFrom Astrobiology Magazine

Page 4 CONTROVERSY ERUPTS OVER "STERILE" ANTARCTIC LAKEBy Alison George

Page 4 DA VINCI PROJECT READY TO PLAY FOR ANSARI X PRIZEDa Vinci Project release

Page 5 DIGGING FOR LIFE IN THE DEADEST DESERTBy Michael Coren

Page 5 SPOOKY SPACEFLIGHT: QUANTUM ENTANGLEMENT AND DEEP-SPACE PROPULSIONBy Mark Waldron

Page 7 SATURN'S MOON TITAN: PLANET WANNABE (INTERVIEW WITH JONATHAN LUNINE)By Henry Bortman

Announcements

Page 8 NASA SELECTS PROPOSALS TO STUDY GLOBAL CARBON CYCLING NASA release 2004-258

Mission Reports

Page 9 CASSINI UPDATESNASA/JPL releases

Page 11 MARS EXPLORATION ROVERS UPDATESNASA/JPL releases

Page 13 MARS EXPRESS: ESCARPMENT AND LANDSLIDES OF OLYMPUS MONSESA release

Page 13 MARS GLOBAL SURVEYOR IMAGESNASA/JPL/MSSS release

Page 14 MARS ODYSSEY THEMIS IMAGESNASA/JPL/ASU release

Page 14 ROSETTA'S VIEW OF HOMEESA release

CLIMATE CHANGE COULD DOOM ALASKA'S TUNDRABy David StauthOregon State University release

3 August 2004

In the next 100 years, Alaska will experience a massive loss of its historic tundra, as global warming allows these vast regions of cold, dry, lands to support forests and other vegetation that will dramatically alter native ecosystems, an Oregon State University researcher said today. Polar regions such as Alaska will be among the first to illustrate the profound impacts of climate change, said Dominique Bachelet, an associate professor in the OSU Department of Bioengineering and expert on the effects of climate change on terrestrial vegetation. She spoke at the annual meeting of the Ecological Society of America.

More precipitation, an overall loss of soil carbon, a probable reduction in forest fires and a likely increase in insect and pathogen attacks on trees are also projected by some of the most sophisticated computer models yet developed, Bachelet said.

"The effects of climate change in Alaska will be among the most visible in the world," Bachelet said. "The tundra has no place else to go, and it will largely disappear from the Alaskan landscape, along with the related plant, animal and even human ecosystems that are based upon it."

The newest research suggests that 90 percent of Alaska's tundra that was present in 1920 will be gone by 2100, less than a century from now, under one of the climate models projecting the most extreme warming. A model with

more conservative estimates indicates that 77 percent of the tundra will disappear during that time. Temperatures have already been above the historical norm in Alaska for the past 17 years. But about 100 years from now, the average annual temperature in Alaska may soar up to 13 degrees Fahrenheit higher in the worst case scenario predicted by climate models.

Tundra is a cold, comparatively dry ecosystem that now covers much of Alaska, characterized by the permanently frozen deep soil layers called permafrost, few or no trees, grasses and dwarf shrubs, and an extremely short growing season. But it also supports brown bear, wolf, wolverine, caribou, arctic hare, mink, weasel, lemming and millions of migrating waterfowl. In summer it can feature thousands of lakes and large marshy areas.

According to Bachelet, despite some of the criticisms aimed at them, climate models appear to work better and achieve higher accuracy over longer rather than shorter periods of time.

"If you ask these models to predict exactly what the global climate will be in the summertime five years from now, that's much more difficult because of the natural, short-term variations in weather and climate," Bachelet said. "But based on everything we've learned, when we predict what's going to happen during a 20-year period about a century from now, we can be fairly confident. We also test these models by running them backward into the past, and the results are quite accurate."

Bachelet and her colleagues at OSU and the U.S. Forest Service have developed the Dynamic Global Vegetation Model MC1, an improved way of predicting what certain climate scenarios will mean in terms of vegetation growth, plant and soil processes, carbon storage or emissions, forest fire and

Marsbugs: The Electronic Astrobiology Newsletter, Volume 11, Number 31, 8 August 2004

other important ecological effects. The latest simulations with this model were done with Alaska as a prelude to work with much of the world's Arctic region, Bachelet said.

"Some of this is not that surprising; the winters in Alaska are already getting milder and the summers warmer," Bachelet said. "Were already seeing glacial melting, movement in fish migrations, Inuits who are having to change their fishing and hunting habits because of melting ice."

But any changes so far pale in comparison of what's to come, and fairly soon, Bachelet said. Among the predictions: Boreal mixed forests could yield to a maritime and temperate conifer

forest much like those of southeast Alaska, and cover huge areas of Alaska.

The only large area of remaining tundra in Alaska 100 years from now will be on its north coast.

Because of increases in precipitation and despite an increase in statewide biomass, forest fires should become less frequent overall and could shift from central Alaska to the northeast.

Insects and pathogens, which can adapt more readily to changing environmental conditions, may cause massive epidemics of plant disease and insect attack—in some cases causing large forest die-offs that could then lead to more fires, adding complexity to the picture.

The average annual temperatures in much of Alaska could increase by more than 13 degrees above a 1920-2000 average by the last decade of the 21st century, according to the most extreme climate scenario, and eight degrees under a more conservative scenario.

There are some variables that could affect these projections, Bachelet said, such as major changes in ocean circulation patterns that could have unpredictable effects on regional climate. One such change that has been suggested—a shutdown of a major ocean current and circulation pattern in the North Atlantic ocean that currently is responsible for warming much of Europe—might have other ripple effects that would cause regional climate impacts to vary.

"You'll always have some uncertainties when you are trying to predict the localized impact of global climate change," Bachelet said. "But it's pretty certain that our global climate is warming up, and at this time, it looks like one of the major impacts will be on the tundra ecosystem of Alaska."

Contacts:David StauthPhone: 541-737-0787

Dominique BacheletPhone: 360-570-2015

An additional article on this subject is available at http://www.spacedaily.com/news/climate-04zzi.html.

FLYING DINOSAUR NEEDED A BIRD'S BRAIN By Jeff HechtFrom New Scientist

4 August 2004

Flight was built into the brain as well as the body of Archaeopteryx. The oldest known bird shares many skeletal features with its dinosaur ancestors, such as teeth and a long bony tail. Yet a CAT scan reveals that Archaeopteryx had the large brain and optic lobes of modern birds, not the brain of a dinosaur, says Angela Milner of the Natural History Museum in London, UK.

It is relatively easy to study how a fossil skeleton may have been adapted for flight. However, navigating in a three-dimensional environment also requires a specialized brain. Modern birds have an enlarged brain, optic lobes and keen ears with spatial sensing organs, but little had been known about the brain of Archaeopteryx. So Milner's team investigated the London specimen of Archaeopteryx, the only one suitable for scanning. A three-dimensional image created from the scan shows the bird had a relatively large cerebellum, "the area where all thecoordination and control goes on", Milner says.

Read the full article at http://www.newscientist.com/news/news.jsp?id=ns99996244.

ROCKING THE CRADLE OF LIFE—FINDING THE PREBIOTIC BOUNDARYFrom Astrobiology Magazine

4 August 2004

To find what many consider to be the earliest fossil evidence for life on Earth, one starting point might be to book a flight to the Pilbara region in Western Australia. On arrival in this gold-mining district, the searcher finds strange rock layers, many shaped like egg-cartons. Billions of years ago, these colonies may have formed as microbial reef deposits. Under closer examination, a few of these rocks reveal microscopic segmented shapes that hint at their complex and possibly biological origin. Given that many of these rock layers date back 3.45 billion years, their detailed study has attracted interest in the search for life on early earth.

Called stromatolites (from the greek for "stoney carpet") such sediments may be the remains of microbial mats that grew in stages: first seeking nutrients and then incorporating minerals into their rock layers. Examples of living stromatolites can be seen today at Hamelin Pool, Shark's Bay Western Australia. It is also suggested that on early earth, stromatolites may have formed chemically in underwater, hot vents where minerals precipitated in sculpted layers. This explanation does not require biology.

Questions about the origin of these sediments thus center on the fine details of how they arose. Are these true fossils or some volcanic remant? Did they originate from chemical or biological starting materials, a key distinction that fuels a spirited debate and attention in a research field called paleobiology.

The Apex Chert microfossils (above) formed in association with hot fluids near a volcanic structure. Image credit: UCLA.

The mystery underlying Earth's early fossil record is complicated not just because these rocks are very old, but also because on Earth, biology itself was very young. Pre-Cambrian organisms lacked hard parts that could be preserved once the hosts died and decayed. Little from the first organisms could be preserved. The early diversity of life also was limited, so hospitable locations for fauna to take root were more narrowly defined.

Other than the interest of paleobiologists studying when life started, this controversy highlights deeper questions for astrobiologists: how to detect life. Can shape (or morphology) be used to identify simple, primitive life forms? What kinds of evidence would compel a definitive conclusion about some future martian fossil, particularly if a candidate rock had preserved just the incomplete biological outline that only vaguely resembled a microbe once seen on Earth?

Astrobiology Magazine had the opportunity to talk with researcher Nicola McLoughlin of Oxford University's Department of Earth Sciences about her work on whether the earliest putative microfossils give a useful starting date for posing the big question. When did life begin?

Astrobiology Magazine (AM): What about the Western Australian finds first interested you?

Nicola McLoughlin (NM): The shear age and relatively good preservation of the Warrawoona Group, the unrivalled exposure of stromatolites, the challenge and opportunity to understanding the co-evolution of the early

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bio/litho/hydro/atmospheres encoded in these rock. My stromatolite research is focused on the Strelley Pool and North Pool Cherts. I have also spent a lot of field time mapping the (infamous) Apex Chert.

Modern reef colonies, Sharks Bay, Western Australia.

AM: Do you work with Martin Brasier on whether these are chemical [and not biological] in origin?

NM: Yes. In studying putative Archean microfossils and stromatolites our group adopts the approach that a biological origin should not be accepted until all plausible abiogenic explanations for their origin have been examined and can be falsified.

Herein I the term stromatolite in the non-genetic sense: as attached, laminated, lithified sedimentary growth structures that accrete away from a point or limited surface of initiation (Semikathov et al., 1979). This definition describes the fundamental morphological and textural characteristics of a stromatolite, whilst encompassing multiple or indeterminate origins.

The biogenicity of Archean stromatolites is much debated due to their relative simple macro-morphology, the diagenetic destruction of organic microfossils and microfabrics (in the case of the Warrawoona group by pervasive syn- and post-depositional silicification—or conversion to silica). These challenges are coupled with an increasing realization of the extent of seafloor chemical precipitation during the early Precambrian and the morphologically diverse precipitates that can result.

My ongoing research on the Strelley Pool Chert indicates extensive, primary chemical precipitation that produced the large horizons of crystal fan arrays. The conical stromatolites are intimately related with the crystal fans, often inheriting the topography of underlying crystal fans, raising the possibility that the stromatolites formed by similar processes.

Our null hypothesis is that abiogenic crystallisation can produce complex undulose bedforms by the interaction of multidirectional seafloor currents with cohesive sediments—or "crystalline pavements" if you like. In an attempt to better understand these processes we are conducting experimental work to constrain the stromatoloid macro-morphologies and microfabrics that can be produced by abiogenic chemical precipitation.

Whilst the possibility remains that chemical precipitation of the Strelley Pool Chert stromatolites was microbially mediated, the lack of convincing relict microbial mat fabrics currently renders this hypothesis unproven . In addition to petrography and morphological modelling, we are also analysing stromatolite laminae for elevated levels of elements known to be concentrated by microbial mats.

AM: Can you broadly describe the mechanism of hydrothermally-heated graphite formation as an alternative to the microbial explanations?

NM: This mechanism has been suggested for the origin of microfossil like structures in black, kerogenous, hydrothermal cherts, principally the Apex "microfossils" (Schopf structures), and possibly also the Dresser/North Pole "microfossils" and " microfossils" found in cherts of the Mount Ada Basalt.

It is envisaged that processes such as Fischer-Tropsch (FTT) synthesis could produce simple carbon compounds deep in the Archean crust.

[Note: These chemical reactions produce long chain hydrocarbons terminated with an alcohol group. If these can react, surfactants or detergent-like molecules form, which would effectively precede the first primitive cell walls. In detail, FTT is a also process where carbon dioxide [CO2] is converted to methane and short chain hydrocarbons by reaction with hydrogen [H2] possibly derived from serpentinization reactions, this process is catalyzed by magnetite and Ni-Fe alloys common in Archean ultramafic rocks. Significantly this process can produce carbon [C] compounds with [carbon-13 isotopes] d13C values of -20 to -54 parts per thousand previously taken as an indicator of biogenicity.]

Circulating hydrothermal fluids could carry these carbon [C] compounds up the dyke system, possibly entraining further re-mobilized carbon [C] on its way, agglomerating as it moves and being trapped by the cherts crystallizing in the dyke/vent system. Further morphological modification of these organic rich artifacts or pseudofossils may then occur by later re-crystallization. In this way hydrothermal cherts with complex fracture-fill fabrics could contain clots of carbon [C] compounds with "microfossil" morphologies. No such "microfossils" structures are reported from stromatolitic horizons in the Warrawoona Group, but it has been suggested that if exhaled from a vent these pseudofossils could be trapped within an accreting stromatolite, perhaps also concentrating into amorphous organic rich layers.

AM: Do you have a favored result for any of the more undisputed claims to finding the earliest fossil forms of life? What is the best date now for the beginning of this microbial fossil record?

Canadian stromatolites, Great Slave.

NM: Probably the oldest, most convincing biogenic stromatolites I have seen are from the 2.7 billion year [giga-year, or giga-annum, Ga] Fortesque group, with good micro-textural preservation, significant morphological complexity and diversity. The challenge is to bridge the gap between these stromatolites and the Warrawoona structures. Further systematic study of stromatolites from the Steep Rock Group 2.9-2.7 billion year old [Ga] Northen Canada and other horizons from Africa and India, may help to resolve, where the biotic-prebiotic boundary can be drawn (good review by Hofmann 2000).

In terms of the micro-fossil record there are two intriguing horizons: the structures recently reported by Furnes et al. (2004) in 3.5 billion year old [Ga] basaltic pillow lavas from South Africa and the 3.2 Ga structures reported by Rasmussen et al. (2002) from the Warrawoona Group. These two horizons are quite different from the examples discussed in Qu 3 and I'd like to see further supporting petrography and geochemistry before accepting their biogenicity. Here in Oxford we are studying a new remarkably well preserved assemblage of microtubular structures from the Warrawoona Group that are morphologically similar to the Furnes et al. material. We hope soon to report

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the criteria used to investigate the biogenicity of these structures and on the basis of their context and mineralogy draw comparisons with results from recent Mars missions.

AM: Is it likely in your opinion that the early Archaean stromatolites were purple and green sulfur bacteria, and not photosynthesizing to produce oxygen?

NM: This is a highly plausible hypothesis given that molecular phylogenetic work by Carrine Blank and others, suggests that Archean microbes were restricted to "hot, deep" geothermal environments. Indeed, there is growing field evidence for a large hydrothermal influence on the depositional environment of the North Pole and more controversially the Strelley Pool Chert stromatolites. These are the types of environments in which chemosynthetic metabolisms may have been viable, but also, where pre-biotic synthesis of simple organic compounds and precipitation of morphologically complex chemical deposits may have occurred. Furthermore, my numerical modeling of the macromorphology of the Strelley Pool Chert stromatolites suggests that they are not strongly phototrophic structures, and thus we are searching for geochemical and micro-textural evidence to investigate a possible chemosynthetic origin.

AM: What kinds of experimental or field techniques are now being applied to help resolve disputes about these examples?

NM: The experimental synthesis of microfossils artifacts using sodium silicate gel and metal salts has been used to gain insights into the abiogenic mechanisms that can generate pseudofossils (Garzia Ruiz 2003). We are conducting analogous experiments using a range of media to investigate the formation of synthetic stromatolites. There is much work to be done coupling this laboratory modeling with numerical modeling of stromatolite form and detailed field analysis of stromatolites. The recent application of complexity analysis to the investigation of stromatolite morphology (Corsetti et al.) is exciting but requires further verification.

Micro-laser Raman is an analytical technique beiing employed by several groups to identify organic remains in Archean cherts , and has proven to be a useful geo-thermometer but a poor indicator of biogenicity. High resolution analysis of coupled isotope systematics including carbon [C], oxygen [O], iron [Fe] and sulfur [S] using techniques such as nano-sims and HRTEM, are being explored to identify microbial processing in both putative microfossils and stromatolites.

AM: Many have criticized a criterion centered around "appearance" of bacteria-like rods as indicating either biogenic or abiogenic origins, whether in stromatolites, fossils or even meteors. Are there diagnostics or techniques one can imagine to help clarify this tenuous relation between structure and origin?

The martian spherules, "blueberries" have become important to clues on an alien landscape. Image credit: NASA/JPL.

NM: The morphology of simple coccoid and rod shaped structures should not be taken alone as an indicator of biogenicity. Analysis of putative microfossil morphology should always be integrated with finescale petrographic and geochemical investigations.

Our group is undertaking quantitative morphological analysis of microfossil and macrofossil (i.e., stromatolite) morphology and find that putative biological and abiological structures often occupy overlapping regions of morphospace. The true pessimist might conclude that morphology is a poor indicator of biogenicity and that the simplest, most primitive life forms are easily mimicked by abiology. The challenge is to identify the types and scales of morphology unique to life—most progress will probably be made by correlating morphological and geochemical biogenicity criteria.

AM: What kinds of topics do you hope your research takes up in future work?

NM: Stromatolites are the most abundant macro-fossils in the Precambrian yet we have a very limited understanding of their morphogenesis and have only partially exploited stromatolite morphology as an indicator of environmental and evolutionary change. There is much work to be done at the interface of sedimentology, paleoobiology, numerical and laboratory modelling to better understand the morphology of stromatolites. More generally I am interested by the co-evolution of the Precambrian atmos/lithos/hydro/bio-spheres in particular the events of the Late Pre-Cambrian, the Ediacara fauna and precursor events to the Cambrian explosion.

Read the original article at http://www.astrobio.net/news/article1115.html.

CONTROVERSY ERUPTS OVER "STERILE" ANTARCTIC LAKEBy Alison GeorgeFrom New Scientist

4 August 2004

Controversy has erupted over Lake Vostok, one of Earth's last unexplored frontiers, which lies deep under the Antarctic ice. Last week a team of Russian and French scientists claimed the lake is sterile. But American scientists insist that it is a potential source of undiscovered life forms, and are worried that Russian plans to drill right through the ice will contaminate it.

At the heart of the dispute is a small but diverse group of microbes found in the single core that has been drilled from the ice above the lake. The Russians and French say these are contaminants from the drilling and testing of samples in the labs. They also argue that the lake itself is too toxic to sustain life because of its extremely high levels of oxygen. If they are right, it would be the first lifeless water body found on Earth. As such, it could help us hone our techniques for the search for life under the polar ice caps on Mars, and in the oceans under the frozen surface of Jupiter's moon Europa.

Read the full article at http://www.newscientist.com/news/news.jsp?id=ns99996238.

An additional article on this subject is available at http://www.spacedaily.com/news/antarctic-04k.html.

DA VINCI PROJECT READY TO PLAY FOR ANSARI X PRIZEDa Vinci Project release

5 August 2004

The Canadian da Vinci Project Team has notified the Ansari X Prize of its intention to launch its rocket on October 2nd, 2004, marking its official entry in the international, commercially-funded space race competition. The da Vinci Project, which unveiled its rocket, Wild Fire, today, joins one American team—in a field of 26—to announce its launch date.

"With two Ansari X Prize teams launching within days of each other for the $10 million prize (U.S.), we truly have a remarkable race for space," said Dr. Peter H. Diamandis, Chairman and Founder of the X Prize Foundation. The recipient of the $10 million prize will be the first team to travel safely to space twice within a two-week period on a privately funded, re-useable spacecraft.

Brian Feeney, who plans to pilot Wild Fire approximately 110 kilometers into suborbital space, said the team is finalizing construction of the rocket as well as logistical details related to the event, which will be held in Kindersley, Saskatchewan.

"We're very close to achieving our mission, thanks to the organizations and individuals that understand the significance of this race," said Feeney. "The da Vinci Project is on the cusp of a new era of space travel for humankind. Our team is proof positive that ingenuity and innovation can overcome the impossible."

In addition, Feeney announced a new sponsor to finance the project. Golden Palace.Com, the world's largest online casino, has signed on as the title sponsor. The Golden Palace.Com Space Program—Powered by the da Vinci Project—is poised to make history. According to sources at the casino, GoldenPalace.com is excited and very proud to be a part of the historic flight of the Wild Fire. In the continuing pursuit for innovative ideas for exposure,

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Golden Palace sources believes the Ansari X Prize competition provides the advertising exposure as well as the added incentive of a history-making event that will eventually serve to benefit all humankind.

The da Vinci Project, which Feeney describes as the largest volunteer technology project in Canada, has achieved several critical milestones since officially entering the competition in 1996. These milestones have included the filing of necessary papers to Canadian government for launch approval; securing the site for launch; the testing of engine components; testing the design and securing a wide range of sponsors including Sun Microsystems of Canada, Blake Cassels Graydon, ANSYS, Hinz Automation and Kindersley Transport.

"The da Vinci Project is emblematic of the spirit of the Ansari X Prize," said Diamandis. "It brings together many of the best and brightest to break down preconceived notions on space travel and prove that we are no longer bound to one planet."

The X Prize Foundation is working with the Federation Aeronautique Internationale (FAI), the international body responsible for all aviation and space world records, to ensure that the Ansari X Prize winner will also receive official international recognition for his achievement. In addition to duration, altitude and distance, the FAI has introduced new world record categories for "minimum time between two consecutive sub-orbital flights in a reusable vehicle" and "number of persons carried in sub-orbital flight".

Read the original news release at http://www.davinciproject.com/beta/index.html.

Additional articles on this subject are available at:http://spaceflightnow.com/news/n0408/05xprize/http://www.universetoday.com/am/publish/da_vinci_project_attempt.html

DIGGING FOR LIFE IN THE DEADEST DESERTBy Michael CorenFrom CNN

5 August 2004

Specialized microorganisms called extremophiles thrive in nuclear waste, volcanic vents, boiling geothermal geysers and even deep inside rocks. Their unique biology allows them to feast on chemicals and radiation that would kill most organisms. But there is a place on Earth so hostile to life that even extremophiles perish: Chile's Atacama Desert.

"Here is the only place where we've really crossed a threshold where we find no life," says Chris McKay a NASA geologist studying the Atacama. "You go to the Antarctic, the Arctic, any other deserts we've been, scoop up dirt and you find bacteria. This is the only place that you would find nothing."

The rocky desert on a high plateau along South America's Andes mountain range appears lifeless. Scientists have been unable to find plants or cells living in many parts of the desert. Even bacteria do not last long in the barren, acidic soil.

Read the full article at http://www.cnn.com/2004/TECH/space/08/04/atacama.desert/index.html.

SPOOKY SPACEFLIGHT: QUANTUM ENTANGLEMENT AND DEEP-SPACE PROPULSIONBy Mark Waldron From Astrobiology Magazine

7 August 2004

In 2001, researchers at the University of Aarhus' Quantum Optics Center in Denmark successfully applied a phenomenon of physics known as quantum entanglement to two specimens of cesium measuring in the trillions of atoms apiece, transferring the quantum state of one group of atoms to the other. Such a transfer is called "quantum teleportation," though it is hardly teleportation of the Star Trek variety. The success in Denmark was noteworthy due to the scale of the experiment; previously the quantum states of only a handful of atoms at a time had been successfully entangled. In addition to whole atoms, there have also been multiple quantum teleportations

of laser beams beginning with a successful experiment in such teleportation conducted by the Australian National University in 2002.

Quantum teleportation, step by step. First, an entangled state of ions A and B is generated, then the state to be teleported—a coherent superposition of internal states—is created in a third ion, P. The third step is a joint measurement of P and A, with the result sent to the location of ion B, where it is used to transform the state of ion B (step 4). The state created for P has then been teleported to B. Image and text Credit: H J Kimble and S J van Enk, Nature.

At present, the primary application of quantum teleportation is viewed as being the development of quantum computing, in which the logic gates of a computer processor are integrated at the atomic level and the logic state of one of the processor's bits would be denoted by the quantum state of an individual atom. (Such a representation of computer logic can be applied to computer's memory as well, creating, in effect, quantum RAM.) In addition, a field of quantum cryptography is being developed from the ability to teleport laser beams, which are capable of carrying information. A teleported laser beam that conveys data would provide an ultrasecure, essentially unbreakable means of encoding sensitive information.

This author would like to propose a third (and even a fourth) application of quantum teleportation, an application with implications at least as far-reaching as the two mentioned above: propulsion. It should be possible to apply quantum teleportation to the problem of deep-space propulsion; not only is such an application possible, but, if implemented, would revolutionize space travel, even to the point of making interstellar travel (both manned and unmanned) truly feasible for the first time. Interestingly, the initial steps of applying teleportation as a propulsion method can be taken using present-day technology.

In brief, the idea is to apply quantum entanglement to ion propulsion. An ion drive system is a form of rocket propulsion which uses a stream of charged particles, or ions, as a rocket exhaust. Ion drives typically yield far lower thrust-to-weight ratios than traditional chemical rockets, but because of their much slower fuel burn rate they can gradually accelerate a spacecraft to speeds that no chemical rocket can reach. Ion propulsion was used on NASA's highly successful Deep Space 1 probe, in the form of a solar-electric drive, that is, an ion drive in which solar panels provide the electrical power that is used to excite the fuel material to produce the ion stream that propels the craft. Interestingly, cesium is one of the materials that have been used as a fuel in ion rockets.

While quantum entanglement and quantum teleportation experiments have to date been confined to entangled specimens of materials within the same laboratory, there is no theoretical limitation on how great a distance quantum entanglement can operate across. In other words, once two groups of atoms have been entangled, that entanglement would still be in effect were one of the entangled specimens moved to the other side of the earth or the solar system. Therefore, were two specimens of cesium (to take one example; other materials would also work) to be entangled on earth, then one of the specimens lofted into space, exciting the earthbound cesium sample to produce ions would result in the space-traveling cesium sample becoming energetically excited and producing ions like its earthbound counterpart. A resulting ion stream, produced without the benefit (or hindrance, for that matter) of any form of internal engine system onboard the spacecraft, could

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propel the craft through space. It would be a kind of engineless drive system, which I am calling the teleportation drive.

The actual engine and, even more importantly, its power source-a nuclear reactor, a solar array, or other form of power generation-would remain on earth along with the earthbound, entangled fuel sample. The benefits of a teleportation drive are most apparent when one considers the various forms of nuclear-electric propulsion that are currently in vogue among NASA researchers. A nuclear-electric drive is a form of ion drive which uses a nuclear reactor to produce the electricity needed to generate its ion exhaust stream. Because of the far higher power levels a nuclear reactor can yield versus solar power, the nuclear-electric drive has risen to the forefront of NASA's ion drive design options in the last few years; being the centerpiece of its Project Prometheus, a long-range research effort into nuclear propulsion systems for spacecraft. For example, the space agency's Jupiter Icy Moons Orbiter (JIMO) project, an offshoot of Project Prometheus, is to be powered by a nuclear-electric drive system.

JIMO will require a 100-foot boom section to separate the craft's instrument payload from its nuclear reactor; large radiator fins will also be mounted on the reactor section to dissipate excess heat generated by the drive. These two requirements-physical separation of the drive from the rest of the craft and radiator fins for heat dissipation-are two distinctive hallmarks of traditional nuclear-driven propulsion system designs. From the standpoint of a government-funded space agency, there are also political drawbacks to placing a nuclear reactor in space. With a teleportation drive, there are no radiator fins or separator sections needed on the spacecraft; furthermore, the negative political issues surrounding nuclear space propulsion systems vanish. These, however, are all secondary benefits, as important as they are. The primary benefit of the teleportation drive is that it effectively removes all limitations on how much power can be generated to propel the spacecraft.

The need for a high-yield yet compact power source has been the bane of nuclear propulsion designs in the past; it is, for instance, a major technical barrier to seeing the realization of NASA's VASIMR (Variable Specific Impulse Magnetoplasma Rocket) drive, under development at the Johnson Space Center in Houston under the direction of Dr. Franklin Chang-Diaz. Because the power source of a teleportation drive is earthbound, it can be arbitrarily large. A very large nuclear reactor-which now of course does not need to be flown into space-can provide the power for propelling a very small spacecraft. Such a craft could enjoy a very high thrust-to-weight ratio, potentially greater than that of chemical rockets, with obvious benefits in terms of maximum attainable speed when combined with the teleportation drive's inherently high fuel efficiency (high specific impulse, in rocketry parlance). The new thrust levels attainable by a teleportation drive might also allow for the craft to take off directly from the earth's surface, without the need for chemical rockets to place it in space, something never before attainable with any form of ion drive. Finally, in the past only two forms of power source have been put forward for ion drives: solar and one or another form of nuclear power.

Since a teleportation drive's power source remains earthbound, any method of generating electricity can be applied to power the drive, including hydroelectric power (imagine Hoover Dam generating the power for a deep space probe's engine). There is also an economy of scale that applies to the earthbound power source in that the same source can be used to excite multiple entangled fuel specimens: the same plant can therefore be used to accelerate multiple spacecraft.

There is another propulsion application for quantum entanglement which, while probably requiring more R&D investment than the teleportation drive, would have even greater (as in, several orders of magnitude greater) speed benefits for a spacecraft: applying quantum entanglement to produce the first viable photon drive. A photon drive system uses nothing but a beam of photons (a beam of light if the photons fall in the frequency spectrum of visible light) to propel a spacecraft. The photon drive is a theoretical possibility that has been talked about for decades but has never been practical due to the immense power requirements it would take for such a drive to generate sufficient thrust to propel a spacecraft.

An example of the simplest photon drive imaginable has been given in the past: if a flashlight were to be turned on in space and left there by an astronaut, its light beam would provide a miniscule amount of thrust to the flashlight, but not nearly enough to accelerate it to any noteworthy speed before the battery burned out. A photon drive requires essentially no fuel,

only power. In other words, a photon drive has an extremely high specific impulse but a very low thrust-to-weight ratio.

The great advantage to a photon drive is that if its power requirements were to be overcome, a photon drive system could eventually accelerate a spacecraft up to very high speeds-even, theoretically, close to the speed of light. However, both nuclear fission and nuclear fusion fall short in terms of generating the necessary power, at least from a reactor small enough to be realistically carried onboard a spacecraft. A matter-antimatter reaction of a sufficient size could generate the required power, but antimatter is exquisitely expensive to produce at the time of this writing, and containment and manipulation technologies for it are still in early stages of development. Thus, a photon drive powered by matter-antimatter reaction is currently not a viable option. There is another option.

Applying quantum teleportation to a photon drive (to produce what I am dubbing the telephotonic drive) would remove the one great engineering obstacle (i.e., power generation) to producing a viable photon drive system. Recall from earlier in this article that laser beams (i.e., concentrated streams of photons) have been successfully teleported. Without knowing it, the researchers who accomplished this feat created a basic telephotonic drive in the course of their experiments. In the case of a telephotonic drive powerful enough to propel a spacecraft, earthbound electric plants (nuclear or otherwise) would generate the power for a laser beam which would then be teleported to a spacecraft.

While even a dedicated nuclear power plant may not generate sufficient power to create a laser powerful enough to realistically provide propulsion for a spacecraft, there is no reason why a single spacecraft would need to be powered by a single entangled laser beam; multiple power plants, perhaps widely spread geographically over the earth's surface, could generate multiple laser beams which would then be teleported to adjacent "cells" to the rear of the spacecraft, producing an array of high-power laser beams that would collectively propel the craft—potentially to near the speed of light. Incidentally, since entanglement information is itself conveyed (either by laser or radio waves) at the speed of light, and since even a telephotonic drive could never, according to relativity theory, propel a craft up to the speed of light, a spacecraft propelled by a telephotonic drive could never "outrun" its lasers' required entanglement information.

A variation on the telephotonic drive concept involves using entangled lasers, generated on the earth's surface, to create a laser fusion drive. The idea behind the laser fusion drive (which, like the photon drive, has been talked about for years but has never been developed) is that pellets of frozen hydrogen fired out of the rear of a spacecraft like a machine gun are individually struck by powerful laser beams, igniting each one in an individual fusion reaction; the resulting series of energy bursts push the craft forward. There is an engineering obstacle in creating lasers powerful enough to fuse the hydrogen pellets; as in the case of the telephotonic drive, teleporting entangled laser beams from earthbound power plants to the spacecraft would overcome this obstacle. While an entangled laser fusion drive would not accelerate a spacecraft to the speeds attainable by a telephotonic drive, or even a teleportation drive, I suspect that it is more immediately realizable from a practical engineering standpoint than either of those propulsion concepts.

The first step, of course, towards implementing any of these drive schemes is to test them on the ground. As stated before, the theory of the telephotonic drive has, in effect, already been proven; it only needs scaling up (though vastly so) in order to become a viable propulsion method. The successful entanglement of lasers also proves the conceptual soundness of the entangled laser fusion drive. The teleportation drive could be proven, in concept, for relatively little cost or resources. There are commercially available small ion rockets designed for use as maneuvering thrusters on satellites and space probes. An experiment to prove the theoretical soundness of the teleportation drive would involve taking one of these commercial thrusters and entangling its fuel to another specimen of the same element. If, upon activation of the thruster, the entangled second specimen generated an ion stream, the theory would be proven. Such an experiment is well within the resources of even small government or university physics laboratories.

Spacecraft propulsion is therefore a third practical application of quantum teleportation, in addition to quantum computing and quantum cryptography. There is, however, a fourth application, one which deserves its own treatment in a separate paper but which I will briefly introduce here because of its relevance to the propulsion systems outlined above. That application is wireless power transmission. NASA and the U.S. Department of Energy

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have, over the last three decades, studied various concepts for generating electric power in space and then beaming it (via microwave in most design concepts) to the earth's surface for public use. In the late 1970s the DoE, under the Carter Administration, studied the possibility of orbiting large satellites that would collect solar energy and beam it to earth. The idea was unviable due to the immense size of the solar arrays involved (on the order of tens of square kilometers). There is also a problem presented by beaming energy to earth in this manner, as such a beam would have a tendency to diffract in the earth's atmosphere.

However, aided by advances in solar cell technology, much smaller solar arrays could today be placed in orbit around the sun, perhaps within the orbit of Mercury (naturally the arrays would need to be designed to withstand intensive bombardment by heat and radiation; the upside would be that the proximity to the sun would also allow for greater power collection). A resulting microwave beam generated with the energy collected could be quantum-teleported directly to the earth's surface. Aside from the obvious immediate benefits of such an efficient power generation system, these satellites could also provide the power input for a telephotonic or entangled laser fusion drive. Thus quantum teleportation could provide an "end-to-end solution" for propelling a craft up to near-light speeds.

Left: the strange universe of Einstein is more familiar to science-fiction writers if spooky action at a distance can be bridled for a ride. Image credit: Einstein archives. Right: a highly efficient ion engine nozzle, driven by an exhaust of charged particles. Image credit:JPL/SSE Roadmap.

Einstein was uncomfortable with the idea of quantum entanglement, referring to it as "spooky action at a distance". By applying quantum teleportation to deep-space propulsion, that element of distance may be measurable in light-years.

Read the original article at http://www.astrobio.net/news/article1124.html.

SATURN'S MOON TITAN: PLANET WANNABE (INTERVIEW WITH JONATHAN LUNINE)By Henry Bortman From Astrobiology Magazine

9 August 2004

In January 2005, the European Space Agency's (ESA's) Huygens Probe will descend through Titan's atmosphere, sending back a detailed picture of the chemical interactions taking place there and, hopefully, giving scientists a glimpse into the chemistry that took place on early, prebiotic Earth. The Huygens Probe is part of the Cassini-Huygens mission to explore Saturn and its rings and moons. Titan is the only moon in our solar system with an atmosphere. Organic chemistry detected in that atmosphere has sparked the imagination of planetary scientists like Lunine. Lunine is the only U.S. scientist selected by the ESA to participate in the three-member Huygens Probe interdisciplinary science team.

Astrobiology Magazine (AM): One of the major goals of the Cassini-Huygens mission is to explore Titan. What makes this distant moon so interesting?

Jonathan Lunine (JL): If Titan were in orbit around the sun, it would have been a major target of solar system exploration, possibly before Cassini. And I say that because it's a body the size of a planet (larger than Mercury), which has a dense atmosphere of nitrogen and methane. And so, if we were to look at it in the sky, we would say: Hey, here is a planet that has a dense

atmosphere. The Earth has a dense atmosphere. Venus has a dense atmosphere, but it's hot enough to melt lead. Mars may have had a dense atmosphere in the past, but it's cold and tenuous now. If we want to explore a planet in the solar system which is somewhat like the Earth, [Titan is] the place to go.

Because Titan's in orbit around Saturn, though, and not in orbit around the sun, it kind of gets a bad rep. People ignore it; they think of it as if it were a moon; and it is a moon, but it's a moon with an atmosphere. And it's large enough that probably a lot of the phenomena that we see going on on Earth are going on there—except for biology.

Left: Jonathan Lunine of the Lunar and Planetary Laboratory at the University of Arizona. Image credit: Space.com. Right: the haze of an atmospheric layer on Saturn's moon, Titan. With an atmosphere thicker than Earth's, and composed of many biochemically interesting molecules (methane, hydrogen and carbon), Titan's rich chemistry will continue to interest astrobiologists as they look forward to landing a probe on its surface in 2004-2005. Image credit: Voyager Project, JPL, NASA.

AM: It's curious that Titan has an atmosphere, while Ganymede and Callisto (Jupiter's two largest moons), which are larger still, don't. Why is that? How did Titan end up with an atmosphere, while other large moons didn't?

JL: That's one of the three great questions about Titan. Why does Titan have that atmosphere, and Ganymede and Callisto do not? Ganymede and Callisto and Titan are all just about the same size and the same mass, so they have the same density, which means roughly the same composition. And so they're cookie-cutter moons that are formed by the same process. They're the biggest moons, apparently, that can be formed by giant planets, at least as far as we know. Why Titan is different in terms of having an atmosphere is one of the key questions that we don't know the answer to.

One possibility is that because Saturn is farther from the sun (than Jupiter), it was colder during formation. Gasses that could be trapped in the ice at those temperatures and that would have made their way into Titan might not have been trapped at temperatures where Jupiter formed. And therefore Ganymede and Callisto would not have acquired large amounts of nitrogen and methane and so on. A different possibility is that because Jupiter has higher gravity, the impact speeds [of comets] are larger at Jupiter than at Saturn. And so Ganymede and Callisto, in this other picture, would have started out with gas but it would have been ripped away by these impacts. I personally much, much prefer the first story, which was that the ambient conditions were colder at Saturn, and that allowed these very volatile gasses to be trapped in the planet-building material and find their way to Titan.

AM: Will Cassini-Huygens be able to answer the question of how Titan acquired an atmosphere?

JL: I think it will be able to address it in a fairly significant way by being able to gauge the origin of the nitrogen on Titan. If nitrogen on Titan came from ammonia, then we know that it would have been very effectively trapped in the water ice, much better than argon, for example, which is an abundant noble gas. If the nitrogen came in as molecular nitrogen (N2), it would have been trapped to about the same extent as argon—a little bit worse. And so one way to get at this is to measure the argon-to-nitrogen ratio in Titan. If it's high, if it's more than 1 percent, then probably nitrogen came in as N 2, and conditions then were really cold at Titan, and that would say: yeah, this was a temperature difference issue.

If, instead, the argon-to-nitrogen ratio is very, very small, then probably the nitrogen originated as ammonia. Ammonia's not quite as volatile, and could have been present at Jupiter as well as at Titan, and so we'd still be left with something of a mystery in that case. The best Voyager analysis, which actually took almost 20 years after Voyager to get right, puts an upper limit of

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about 6 percent on the argon abundance. And that's not quite good enough to do the comparison. We really need Cassini.

AM: Cassini, or Huygens?

JL: Huygens. We need the gas chromatograph on the Huygens probe. This is one example of a measurement that really only Huygens can do: the measurement of the noble gases [such as argon] in the deep atmosphere.

Titan's atmosphere compared to Earth's. Image credit: JPL/Space Science Institute.

AM: There's a lot of methane in Titan's atmosphere. I've heard people say that if we saw methane in the atmosphere of an extrasolar world, it would be a possible indicator of life, because methane dissipates unless there's a source constantly replenishing it. On Earth, microbes play an important role in generating atmospheric methane. If you don't believe there's biology going on on Titan, where's the methane coming from?

JL: Well that's the second great question about Titan. The first great one was where does the atmosphere come from, why does it have one and Ganymede and Callisto don't? The second great question is how much methane is in the Titan surface-atmosphere system, how much was there at the beginning, and therefore has this chemistry of destroying methane been going on for billions of years, or has it stopped and started in some way?

AM: How will the Cassini-Huygens mission address this question?

JL: Cassini will do the mapping from orbit, looking at large numbers of crater basins, to see if they're filled with liquid; Huygens will get a local view of one area to see if there are on small scales lots of liquid patches. If there are a lot [of these patches], if there is a lot of methane, then the question is: Where did that come from? Almost certainly it was produced abiotically.

On the other hand, if we find evidence that the chemistry has gone on for a long time in Titan's atmosphere, but we don't see methane reservoirs on the surface, that's going to be kind of an oddball situation. Where was the methane that was photolyzed and became ethane or very deep solid-organic deposits? Are we just looking at the last gasp, for example? Or is it buried underneath the surface somewhere and we just can't see it? That's going to be an interesting puzzle.

Is methane, by itself, a good indicator of life? I think the answer is no. What you really want to look for are major chemical constituents that are existing together in an atmosphere that would actually react quickly and destroy each other. So, methane doesn't exist in an oxygen-rich atmosphere. It gets destroyed too quickly. [Methane is present in Earth's oxygen-rich atmosphere because] life provides the methane, and keeps making it fast.

If we see oxygen and methane [in the atmosphere of an extrasolar world], then that might well be a slam dunk for life. Less dramatic, if we saw a lot of methane in an atmosphere of a planet that was at 1 AU [astronomical unit, the distance of the Earth from the sun], from a solar type star, and not, like Titan, very far away, then we might say: Well, gee, how do you get methane to a planet like that, which is too warm? Maybe that is biologically produced.

That might be one situation where methane by itself would give you a potential indicator that there was life, if it was around a warm planet.

AM: What's the third great question about Titan?

JL: The third great question for Titan is the question of how far the prebiotic chemistry has gone. And how far can you go, in an environment like that, toward organized chemistry? It will be hard for Cassini-Huygens by itself to answer that question. It may be able to set the stage for answering it in a future mission.

Read the original article at http://www.astrobio.net/news/article1128.html.

NASA SELECTS PROPOSALS TO STUDY GLOBAL CARBON CYCLING NASA release 2004-258

4 August 2004

NASA, in partnership with the Department of Agriculture and Department of Energy, recently awarded 59 research grants to study changes in the distribution and cycling of carbon among land, ocean, and atmospheric reservoirs, with emphasis on North America. These new research activities are funded as part of the U.S. Climate Change Science Program (CCSP).

"NASA is very proud of this tremendous opportunity for interagency cooperation to help improve and protect our home planet," said Dr. Ghassem Asrar, Deputy Associate Administrator for NASA's Science Mission Directorate. "Carbon is a fundamental building block for life on Earth and we need to better understand how Earth's living system cycles this essential element," he added.

The global carbon cycle affects Earth's climate. Of special interest are factors that control changes in atmospheric carbon dioxide and methane concentrations, as well as the effectiveness of carbon management meant to mitigate increases in these greenhouse gases. Within the CCSP, the North American Carbon Program (NACP) focuses on continental carbon dynamics of special U.S. interest. NACP investigators are endeavoring to close the carbon budget with respect to sources, sinks, and observed changes in atmospheric carbon over North America and adjacent oceans.

"I am delighted to see this solid collaboration among agencies, with NASA's lead, supporting new research that conforms so well to the goals and priorities of CCSP," said Dr. James R. Mahoney, Director of the CCSP. "The North American Carbon Program research is an important step forward in reducing the major uncertainties about global climate change that are the focus of the Administration's Climate Change Research Initiative," he added.

While emphasizing North America, the selected projects will also model and analyze the global carbon cycle and its control of atmospheric carbon dioxide and methane. Regionally focused projects will work to reduce major uncertainties about carbon cycle dynamics outside of North America where NASA's unique observations provide data about remote areas of the Earth.

The 59 proposals selected will receive approximately $14 million a year over a three-year period. The grants will go to researchers at universities, government laboratories, and other organizations that will investigate virtually every aspect of the contemporary carbon cycle. NASA received 301 proposals in response to the research announcement of April 2004. For a complete listing of the research projects selected and their principal investigators on the Internet, visit http://research.hq.nasa.gov. For information about the CCSP on the Internet, visit http://www.climatescience.gov/.

Contact:Gretchen Cook-AndersonNASA Headquarters, Washington, DCPhone: 202-358-0832

An additional article on this subject is available at http://www.spacedaily.com/news/carbon-04i.html.

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CASSINI UPDATESNASA/JPL releases

Saturn's Shadow and Titan's Glow Shed Light on a Complex SystemNASA/JPL release 2004-193, 5 August 2004

The Cassini spacecraft, which began its tour of the Saturn system just over a month ago, has detected lightning and a new radiation belt at Saturn, and a glow around the planet's largest moon, Titan. The spacecraft's radio and plasma wave science instrument detected radio waves generated by lightning.

This artist concept shows how Cassini is able to detect radio signals from lightning on Saturn. Lightning strokes emit electromagnetic energy across a broad range of wavelengths, including the visual wavelengths we see and long radio wavelengths that cause static on an AM radio during a thunderstorm. Some of the radio waves propagate upwards and can be detected at long distances by the radio and plasma wave science instrument on Cassini.

"We are detecting the same crackle and pop one hears when listening to an AM radio broadcast during a thunderstorm," said Dr. Bill Kurth, deputy principal investigator on the radio and plasma wave instrument, University of Iowa, Iowa City. "These storms are dramatically different than those observed 20 years ago."

Cassini finds radio bursts from this lightning are highly episodic. There are large variations in the occurrence of lightning from day to day, sometimes with little or no lightning, suggesting a number of different, possibly short-lived storms at middle to high latitudes. Voyager observed lightning from an extended storm system at low latitudes, which lasted for months and appeared highly regular from one day to the next.

The difference in storm characteristics may be related to very different shadowing conditions in the 1980s than are found now. During the Voyager time period when lightning was first observed, the rings cast a very deep shadow near Saturn's equator. As a result, the atmosphere in a narrow band was permanently in shadow—making it cold—and located right next to the hottest area in Saturn's atmosphere. Turbulence between the hot and cold regions could have led to long-lived storms. However, during Cassini's approach and entry into Saturn's orbit, it is summer in the southern hemisphere and the ring shadow is distributed widely over a large portion of the northern hemisphere, so the hottest and coldest regions are far apart.

A major finding of the magnetospheric imaging instrument is the discovery of a new radiation belt just above Saturn's cloud tops, up to the inner edge of the D-ring. This is the first time that a new Saturnian radiation belt has been discovered with remote sensing. This new radiation belt extends around the planet. It was detected by the emission of fast neutral atoms created as its magnetically trapped ions interact with gas clouds located planetward of the D-ring, the innermost of Saturn's rings. With this discovery, the radiation belts are shown to extend far closer to the planet than previously known.

"This new radiation belt had eluded detection by any of the spacecraft that previously visited Saturn. With its discovery we have seen something that we did not expect, that radiation belt particles can 'hop' over obstructions like Saturn's rings, without being absorbed by the rings in the process," said Dr.

Donald G. Mitchell, instrument scientist for the magnetospheric imaging instrument at the Johns Hopkins University Applied Physics Laboratory, Laurel, MD.

This graph shows the energetic ion and electron data from the Saturn orbit insertion interval on June 30 and July 1, 2004. Ion intensity is shown above the horizontal divider as energy increasing upward. Electron intensity is shown below the horizontal divider as energy increasing downward, as measured by the magnetospheric imaging instrument's low energy magnetospheric measurement system sensor onboard the Cassini spacecraft. Red indicates high particle intensity, blue is low intensity. The vertical energy scales run from 30 kilo-electron volts to several mega-electron volts. Time runs from left to right, with approximately 36 hours of data shown, covering a distance range from Saturn's center between 783,000 kilometers (487,000 miles) at either end, down to about 78,000 (49,000 miles) at closest approach. The region above the rings was found to be devoid of ions and electrons; the region inside the D-ring inner edge was not directly sampled and absent the magnetospheric imaging instrument ion and neutral camera remote sensing would have been assumed empty of energetic particles.

Saturn's largest moon, Titan, is also shining for attention. Cassini's visual and infrared mapping spectrometer captured Titan glowing both day and night, powered by emissions from methane and carbon monoxide gases in the moon's extensive, thick atmosphere.

The glow of Titan's extensive atmosphere shines in false colors in this view of Saturn's gas-enshrouded moon acquired by the Cassini spacecraft visual and infrared mapping spectrometer during the July 2, 2004, flyby. This image is a combination of near-infrared colors, each of which probes different phenomena in the moon.

"Not only is Titan putting on a great light show but it is also teaching us more about its dense atmosphere," said Dr. Kevin Baines, science team member for the visual and infrared mapping spectrometer at JPL. "What is amazing is that

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the size of this glow or emission of gases is a one third the radius of the planet."

The Sun-illuminated fluorescent glow of methane throughout Titan's upper atmosphere—revealing the atmosphere's immense thickness and extending more than 700 kilometers (435 miles) above the surface, was expected. However, the nighttime glow, persistently shining over the night side of Titan, initially surprised scientists.

"These images are as if you were seeing Titan through alien eyes. Titan glows throughout the near-infrared spectrum. If you were an alien it would be hard to get a good night's sleep on Titan because the light would always be on," said Baines.

Cassini Significant Events for 30 July - 4 August 2004NASA/JPL release, 6 August 2004

The most recent spacecraft telemetry was acquired from the Goldstone tracking station on Wednesday, August 4. The Cassini spacecraft is in an excellent state of health and is operating normally. Information on the present position and speed of the Cassini spacecraft may be found on the "Present Position" web page located at http://saturn.jpl.nasa.gov/operations/present-position.cfm.

The S02 background sequence concluded with the execution of a Reaction Wheel Assembly bias activity. S03 began execution on Friday July 30. Initial activities included the loading of Instrument Expanded Block files, and uplink of Cosmic Dust Analyzer (CDA) flight software (FSW) version 9.2.4. The CDA FSW checkout is scheduled for mid August.

Science activities this week mostly centered on Saturn observations. The Magnetospheric and Plasma Science (MAPS) instruments began a campaign to study the influence of the solar wind on Saturn's aurora, while Optical Remote Sensing (ORS) instruments observed Saturn's south pole and aurora. In addition, the Radio and Plasma Wave Science (RPWS) instrument observed Saturn's kilometric radio emissions. RPWS team members also gave a presentation to the flight team recapping science results that had been presented at last month's Committee on Space Research (COSPAR) meeting in Paris, France. Besides Saturn observations, the Imaging Science Subsystem (ISS) observed the trailing side of Iapetus, which will only be seen on a few occasions during tour.

In the last week, 747 ISS images arrived and were distributed. So far since Approach Science began, 15896 ISS images and 4614 Visual and Infrared Mapping Spectrometer (VIMS) cubes have been returned.

In preparation for the Huygens Probe mission early next year, the Spacecraft Operations Office (SCO) Integrated Test Lab has completed ten probe relay fault case tests. Eight tests passed completely. One of the failed cases was an incorrect fault injection and will be repeated at a later date. The second failed case is currently being reviewed.

A project briefing was held as part of the Science Operations Plan update process for S05. This process will complete on Friday, August 6 and a

handoff package presented to the leads for the Science and Sequence Update Process. Assessment meetings were held to review all of the requested changes to the S08 and S09 sequences as part of the Aftermarket process. It appears that all requested changes will fit within available resources. The Target Working Teams and Orbiter Science Teams will be reviewing the requests over the next two weeks and will provide their recommendations at the decision meeting for S08 scheduled for August 13 and for S09 on August 17.

Development of S04 continued this week. A Preliminary Sequence Integration and Validation (PSIV) Science Allocation Panel (SAP) Meeting, Simulation Coordination meeting, and Simulation Procedure Review meeting were held. The simulation meetings were to coordinate testing of a first time use of Inertial Vector Definition in a Radio Science boresight calibration activity.

The Navigation team reported that the post solar conjunction separation angle is currently about 20 degrees. Tracking data quality has improved significantly. The Multi Mission Image Processing Laboratory (MIPL) is performing certification testing of the Solaris 9 upgrades authorized by the Project as a part of the MIPL D32 delivery.

A delivery coordination meeting was held for the Attitude Control Subsystem C-Kernel generation Tool (ACKT) Version 2.0. This Java application queries the Cassini telemetry database for ACS attitude and rate telemetry from which it builds a C-Kernel (CK). The CK will be stored locally in the work directory and can then be published to the file repository.

The Mission Support and Services Office delivered and installed Version 1.3.1 of the electronic command request form (eCRF). All teams and offices supported the Cassini NASA Quarterly Review. A presentation on Phoebe science was given to the flight team this week. Both RADAR and Ultraviolet Imaging Spectrograph teams presented their most recent findings.

A frigid ball of gas in the blackness of space, Cassini's new home, Saturn, appears cool and serene in this natural color image. The spacecraft obtained this view as it sped outward from the planet on its initial orbit. At the left, Saturn's shadow stretches almost completely across the rings, while at the right, the planet's illuminated face appears to gaze down at the far-off Sun.

The Cassini-Huygens mission 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, manages the Cassini-Huygens mission for NASA's Science Mission Directorate, Washington, DC. JPL designed, developed and assembled the Cassini orbiter. For the latest images and more information about the Cassini-Huygens mission, visit http://saturn.jpl.nasa.gov and http://www.nasa.gov/cassini.

Contacts:Carolina Martinez Jet Propulsion Laboratory, Pasadena, CAPhone: 818-354-9382

Donald Savage NASA Headquarters, Washington, DCPhone: 202-358-1727

Additional articles on this subject are available at:http://www.astrobio.net/news/article1111.html

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http://www.astrobio.net/news/article1127.htmlhttp://www.astrobio.net/news/article1128.htmlhttp://www.space.com/missionlaunches/rover_problems_040804.htmlhttp://www.spacedaily.com/news/cassini-04zzg.htmlhttp://www.spacedaily.com/news/saturn-magnetic-04c.htmlhttp://www.spacedaily.com/news/saturn-magnetic-04d.htmlhttp://www.spacedaily.com/news/saturn-titan-04s.htmlhttp://spaceflightnow.com/cassini/040804southpole.htmlhttp://spaceflightnow.com/cassini/040805discoveries.htmlhttp://spaceflightnow.com/cassini/040806saturncolor.htmlhttp://www.universetoday.com/am/publish/structure_saturns_south_pole.htmlhttp://www.universetoday.com/am/publish/cassini_sees_lightning_saturn.htmlhttp://www.universetoday.com/am/publish/outbound_view_saturn.html

MARS EXPLORATION ROVERS UPDATESNASA/JPL releases

More Data from Mars Rover Spirit's First Month Now OnlineNASA internet advisory 2004-190, 3 August 2004

Millions of people have viewed pictures from NASA's Spirit on the Mars Rovers' home page and other Internet sites. Beginning today, a more complete set of science data from Spirit's first 30 martian days is posted on a site primarily for scientists and technical researchers, but also available to anyone who's interested. The first installment of images, spectroscopic measurements, daily reports, and other information from NASA's Mars Exploration Rover project has been posted on NASA's Planetary Data System. It is available with a new "Analyst's Notebook" user interface at http://pds-geosciences.wustl.edu/meran. The home page for the Planetary Data System is http://pds.jpl.nasa.gov. Images are also available from the system's Planetary Image Atlas, at http://pdsimg.jpl.nasa.gov/cgi-bin/MER/search?INSTRUMENT_HOST_NAME=MARS_EXPLORATION_ROVER. Data from Opportunity's first 30 martian days, or "sols," will be added August 24, and data from later portions of both rovers' missions will be added in October.

"All the raw images and selected processed images and other information have been shared with the public since the rovers first reached Mars in January. This release adds other derived images and maps used for planning, all the non-image data from the spectrometers, daily operational reports and activity plans," said Dr. Ray Arvidson of Washington University, St. Louis, deputy principal investigator for the twin rovers' science payload.

"The 'Analyst's Notebook' is designed to help you navigate through the data and understand the synergies," he said. "You can't deal with the Moessbauer spectrometer readings from a given sol without information about other observations that go with it."

"We are proud to be releasing such a comprehensive set of data from the surface science mission of the twin rovers so quickly," said Dr. Jim Garvin, NASA's chief scientist for Mars. "It's a testament to the dedication and commitment of the science and engineering teams that this remarkable collection of information is now available to the entire world for interpretation, education, and to help guide NASA's new exploration focus," added Garvin.

JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover project for NASA. Images and additional information about the project are available from JPL at http://marsrovers.jpl.nasa.gov and from Cornell University, at http://athena.cornell.edu. The Planetary Photojournal, at http://photojournal.jpl.nasa.gov, is another resource for easy public access to images of Mars and other worlds.

Mars Exploration Rover Mission StatusNASA/JPL release 2004-191, 4 August 2004

NASA's Spirit rover has climbed higher into rocky hills on Mars, and its twin, Opportunity, has descended deeper into a crater, but both rovers, for the time being, are operating with some restrictions while team members diagnose unexpected behavior. Both rovers have successfully operated for more than double the span of their three-month primary missions. They have been conducting bonus science in extended missions since April.

This mosaic was produced from pictures taken with the microscopic imager on NASA's Mars Exploration Rover Opportunity on sol 154 (June 29, 2004). It shows one of a series of holes ground by the rover's rock abrasion tool in "Endurance Crater." This time Opportunity stretched its arm, or instrument deployment device, out to a target called "Kettlestone." Grinding for just over two hours on sol 153, Opportunity successfully created a hole 4.5 centimeters (1.8 inches) in diameter and 4.17 millimeters (0.16 inches) deep. Image credit: NASA/JPL/Cornell/USGS.

While Spirit was executing commands on August 1, a semiconductor component failed to power on as intended. The component, a programmable gate array, directly affects usability of the rover's three spectrometer instruments. Subsequent commands for using the miniature thermal emission spectrometer in that day's sequence resulted in repeated error messages. Engineers on the Mars Exploration Rover team at NASA's Jet Propulsion Laboratory, Pasadena, CA, have determined the most likely cause is a timing issue of one instruction reaching the gate array microseconds before another that was intended to precede it. If that diagnosis is confirmed, a repeat could be avoided by inserting a delay between commands that might reproduce the problem, engineers expect. Until then, the rover science team's daily choices for how to use Spirit do not include using the miniature thermal emission spectrometer, the Moessbauer spectrometer or the alpha particle X-ray spectrometer.

"While we're being very cautious in how we operate today and tomorrow, we expect to verify the problem and resolve this issue with a relatively easy workaround," said JPL's Jim Erickson, project manager for the twin rovers.

Spirit has driven to a bedrock exposure near the top of a spur of the "Columbia Hills." The location sits about nine meters (30 feet) above a plain that the rover crossed for months to get from its landing site to the hills. Planners intend for Spirit to spend more than a week at this site, inspecting the rock exposure, dubbed "Clovis," and recording the panoramic scene from this viewpoint.

Halfway around Mars, Opportunity has driven about 20 meters (66 feet) into "Endurance Crater," examining increasingly older layers of bedrock as it advances. If assessments of traversability continue giving positive indications, the rover team plans next to send Opportunity counterclockwise across the inner slope of the crater to study possible targets of dune tendrils, boulders and the base of a cliff.

Four times in the past two weeks, Opportunity has sent error messages while successfully taking pictures with its microscopic imager. One hypothesis for the cause is degradation of flexible cabling that runs down the rover's robotic arm to the instrument. As a precaution while undertaking further analysis, the rover team is treating use of the arm as a consumable resource, with cable wear each time the arm is moved decreasing the possible number of future microscopic images.

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Marsbugs: The Electronic Astrobiology Newsletter, Volume 11, Number 31, 8 August 2004

"We are being very conservative about this because we certainly don't want to do anything to jeopardize the instruments," said Dr. Ken Herkenhoff of the U.S. Geological Survey Astrogeology Team, Flagstaff, AZ, lead scientist for both rovers' microscopic imagers. "We are running more diagnostics that we hope will identify the problem. There are potential explanations that would mean we do not have to treat arm use as a consumable."

Erickson said, "We will no doubt have more issues with them in the future. We'll do everything we can to milk the most value out of them while they are usable, but they won't last forever."

Rocks Tell Stories in Reports of Spirit's First 90 Martian Days NASA/JPL release 2004-194

5 August 2004

Scientific findings from the NASA rover Spirit's first three months on Mars will be published Friday, marking the start of a flood of peer-reviewed discoveries in scientific journals from the continuing two-rover adventure. Researchers using Spirit's toolkit of geological instruments from early January into April read the record from rocks and soils in the rover's landing area and found a history of volcanic blanketing, impact cratering, wind effects and possible past episodes of scant underground liquid water. Evidence for the water comes from mineral alteration in the veins, inclusions and coatings of some rocks. Eleven reports with 120 collaborating authors from around the world lay out details in the August 6 issue of the journal, Science.

As NASA's Mars Exploration Rover Opportunity creeps farther into "Endurance Crater," the dune field on the crater floor appears even more dramatic. This false-color image taken by the rover's panoramic camera shows that the dune crests have accumulated more dust than the flanks of the dunes and the flat surfaces between them. Also evident is a "blue" tint on the flat surfaces as compared to the dune flanks. This results from the presence of the hematite-containing spherules ("blueberries") that accumulate on the flat surfaces. Image credit: NASA/JPL/Cornell.

"This is the first batch," said Dr. Steve Squyres of Cornell University, Ithaca, NY, principal investigator for the science payload on both Mars Exploration Rovers. "You'll be seeing a lot more publications in months ahead and, no doubt, for many years to come based on information from Spirit and Opportunity. These machines just keep going and going, so the science just keeps coming and coming." Dr. Jim Garvin, NASA's Chief Scientist for Mars added, "This is the basis for beginning the remarkable scientific legacy of the rovers that will not only rewrite our textbooks about Mars, but also pave the way for human exploration."

The rovers completed three-month primary missions in April, then began bonus exploration in extended science missions. "Spirit and Opportunity have really done yeoman's work, still operating after more than twice as long as their original assignments. We don't know how much longer they'll keep working, but while they do we promise to keep them busy," said Jim Erickson, project manager at NASA's Jet Propulsion Laboratory, Pasadena, CA. Both rovers were equipped and targeted to collect evidence about past environmental history, especially any history of liquid water, since life as we know it depends on water. Spirit is exploring inside Gusev Crater, an ancient Connecticut-sized impact basin that was selected as a landing site because it may have once held a giant lake fed by flows of water though a large valley that empties into the crater.

The new reports state that, in its first three months, Spirit found no evidence of lake-related (lacustrine) deposits. "Any lacustrine sediments that may exist at this location within Gusev apparently have been buried by lavas that have undergone subsequent impact disruption," says the lead-off paper by Squyres and 49 other rover science team members. Spirit has subsequently driven to a different location—nearby hills over 3 kilometers (2 miles) away—to continue exploring.

Dr. John Grant of the National Air and Space Museum, Washington, and co-authors report that the rocks on the plain that Spirit explored during its primary mission increased about fivefold in maximum size as the rover got closer to an old 210-meter (690-foot-wide) impact crater. The impact that excavated the crater brought volcanic rocks to the surface from as deep as 10 meters (33 feet). Several papers give evidence that rocks in the area are a volcanic type called basalt and bear the mineral olivine. These include reports by Cornell's Dr. Jim Bell with collaborators using Spirit's panoramic camera and by Dr. Dick Morris of NASA Johnson Space Center, Houston, with collaborators using the Moessbauer spectrometer. Dr. Hap McSween of the University of Tennessee, Knoxville, and co-authors state, "These basalts extend the known range of rock compositions comprising the martian crust."

Dr. Ken Herkenhoff of Flagstaff, AZ, offices of the U.S. Geological Survey and other scientists using Spirit's microscopic imager offer findings that rocks cut into by the rover's rock abrasion tool have coatings and bright veins apparently from mineral alteration after the rocks formed. Dr. Ralf Gellert of Max-Planck-Insitut-fur-Chemie in Mainz, Germany, and other users of Spirit's alpha-particle X-ray spectrometer report that bromine in the veins suggests the alteration resulted from exposure to water. Dr. Phil Christensen of Arizona State University, Tempe, and collaborators using Spirit's miniature thermal emission spectrometer say the rock's coatings are consistent with exposure to moisture while buried. Dr. Ray Arvidson of Washington University, St. Louis, and co-authors describe cohesive texture in soils and rock coatings, which they suggest could result from brief moist periods in the past.

Magnet experiments indicate almost all sampled dust particles in Mars' atmosphere contain magnetic minerals, according to a paper by Dr. Preben Bertelsen of the Niels Bohr Institute, Copenhagen, Denmark, and others. Dr. Ron Greeley of Arizona State University and co-authors found that winds from the northwest grooved some rock surfaces and shaped sand ripples in the past. They report that the way rock dust accumulates during grinding by Spirit's rock abrasion tool shows that wind still comes from the same direction.

JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover project for NASA's Science Mission Directorate, Washington. Additional information about the project is available from JPL at http://marsrovers.jpl.nasa.gov/ and from Cornell University, Ithaca, NY, at http://athena.cornell.edu.

Contacts:Guy Webster Jet Propulsion Laboratory, Pasadena, CAPhone: 818-354-6278

Don SavageNASA Headquarters, Washington, DCPhone: 202-358-1727

Additional articles on this subject are available at:http://www.astrobio.net/news/article1112.htmlhttp://www.astrobio.net/news/article1123.htmlhttp://www.spacedaily.com/news/mars-mers-04zzzzzzh.htmlhttp://www.spacedaily.com/news/mars-mers-04zzzzzzi.htmlhttp://www.spacedaily.com/news/mars-mers-04zzzzzzj.htmlhttp://www.spacedaily.com/news/mars-mers-04zzzzzzk.htmlhttp://www.spacedaily.com/news/mars-mers-04zzzzzzl.htmlhttp://www.spacedaily.com/news/mars-mers-04zzzzzzm.htmlhttp://www.spacedaily.com/news/mars-mers-04zzzzzzn.htmlhttp://spaceflightnow.com/mars/mera/040804status.htmlhttp://spaceflightnow.com/mars/mera/040805rocks.html

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Marsbugs: The Electronic Astrobiology Newsletter, Volume 11, Number 31, 8 August 2004

MARS EXPRESS: ESCARPMENT AND LANDSLIDES OF OLYMPUS MONSESA release

5 August 2004

Perspective view of scarp around Olympus Mons.

These images from ESA's Mars Express show the western flank of the shield volcano Olympus Mons in the Tharsis region of the western martian hemisphere. These images were taken by the High Resolution Stereo Camera (HRSC) during orbit 143 from an altitude of 266 kilometers. They were taken with a resolution of about 25 metres per pixel and are centered at 222° East and 22° North. North is to the left.

Olympus Mons, complete with escarpment and aureole.

The images show the western part of the escarpment, rising from the surface level to over 7000 meters. In the foreground, part of the extensive plains west of the escarpment is shown, known as an "aureole" (from the Latin for "circle of light"). See the black and white MOLA image for the full extent of this aureole. To the north and west of the volcano, these "aureole" deposits are regions of gigantic ridges and blocks extending some 1000 kilometers from the summit like petals of a flower. An explanation for the origin of the deposits has challenged planetary scientists for decades. The most persistent explanation, however, has been landslides. Large masses of shield material can be found in the aureole area. Several indications also suggest a development and resurfacing connected to glacial activity.

The color image has been created from the nadir (vertical view) and three color channels on the HRSC. Image resolution has been decreased to 50% for use on the internet.

Perspective view of scarp around Olympus Mons.

Perspective view of scarp around Olympus Mons.

Read the original news release at http://www.esa.int/SPECIALS/Mars_Express/SEM2K1W4QWD_0.html.

An additional article on this subject is available at http://www.universetoday.com/am/publish/slides_olympus_mons.html.

MARS GLOBAL SURVEYOR IMAGESNASA/JPL/MSSS release

29 July - 4 August 2004

The following new images taken by the Mars Orbiter Camera (MOC) on the Mars Global Surveyor spacecraft are now available.

Rippled Mars (Released 29 July 2004)http://www.msss.com/mars_images/moc/2004/07/29/index.html

Fresh Crater (Released 30 July 2004)http://www.msss.com/mars_images/moc/2004/07/30/index.html

Meridiani Outcrops (Released 31 July 2004)http://www.msss.com/mars_images/moc/2004/07/31/index.html

Scene from Ius (Released 1 August 2004)http://www.msss.com/mars_images/moc/2004/08/01/index.html

Mesa in Aureum Chaos (Released 2 August 2004)http://www.msss.com/mars_images/moc/2004/08/02/index.html

Mesas on Depression Floor (Released 3 August 2004)http://www.msss.com/mars_images/moc/2004/08/03/index.html

Layered Rocks of Melas (Released 4 August 2004)http://www.msss.com/mars_images/moc/2004/08/04/index.html

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Marsbugs: The Electronic Astrobiology Newsletter, Volume 11, Number 31, 8 August 2004

All of the Mars Global Surveyor images are archived at http://www.msss.com/mars_images/moc/index.html.

Mars Global Surveyor was launched in November 1996 and has been in Mars orbit since September 1997. It began its primary mapping mission on March 8, 1999. Mars Global Surveyor is the first mission in a long-term program of Mars exploration known as the Mars Surveyor Program that is managed by JPL for NASA's Office of Space Science, Washington, DC. Malin Space Science Systems (MSSS) and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

MARS ODYSSEY THEMIS IMAGESNASA/JPL/ASU release

2-6 August 2004

DCS (Decorrelation Stretch) of Syrtis Major Sand Migration (Released 2 August 2004)http://themis.la.asu.edu/zoom-20040802A.html

Atmospheric Effects in IR Color (Released 3 August 2004)http://themis.la.asu.edu/zoom-20040803A.html

Gale Crater in IR Color (Released 4 August 2004)http://themis.la.asu.edu/zoom-20040804A.html

Lava Flows in IR Color (Released 5 August 2004)http://themis.la.asu.edu/zoom-20040805A.html

Basaltic Crater in Color IR (Released 6 August 2004)http://themis.la.asu.edu/zoom-20040806A.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.

ROSETTA'S VIEW OF HOMEESA release

3 August 2004

This image, taken by ESA's Rosetta comet-chaser spacecraft, shows the Earth-Moon system from a distance of 70 million kilometers. This is close to the

maximum distance reached by the spacecraft so far this year. However, this is a tiny distance compared to Rosetta's epic journey when, in 10 years time, it will have traveled distances of over one thousand million kilometers from Earth, and about 800 million kilometers from the Sun, to meet Comet 67P/Churyumov-Gerasimenko.

The Earth-Moon system taken from Rosetta.

This image was taken by the Navigation Camera System (NAVCAM) on board the Rosetta spacecraft, activated for the first time on 25 July 2004. This system, comprising two separate independent camera units (for back-up), will help to navigate the spacecraft near the comet nucleus. The cameras perform both as imaging cameras and star sensors, and switch functions by means of a refocusing system in front of the first lens. At the comet, extremely high-precision measurements of the relative distance and velocity (between spacecraft and nucleus) will be needed. These are not achievable with the ground-based methods normally used with all other spacecraft or for normal Rosetta trajectory determinations. In the meantime though, the cameras can also be used to automatically track the two asteroids that Rosetta will be visiting during its long cruise, Steins and Lutetia.

Additional articles on this subject are available at:http://www.astrobio.net/news/article1114.htmlhttp://www.spacedaily.com/news/rosetta-04s.htmlhttp://www.spacedaily.com/news/rosetta-04t.htmlhttp://www.universetoday.com/am/publish/rosettas_view_home.html

End Marsbugs, Volume 11, Number 31.

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