Marsbugs: The Electronic Astrobiology NewsletterVolume 12, Number 13, 13 April 2005

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, but individual authors retain the copyright of specific articles. 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 CU STUDY SHOWS EARLY EARTH ATMOSPHERE HYDROGEN-RICH, FAVORABLE TO LIFE University of Colorado release

Page 2 WHERE BACTERIA GET THEIR GENESBy Daniel Stolte

Page 3 "BORN-AGAIN" STARS REVEAL HOW THE EARTH WAS CREATED University of Manchester release

Page 4 IS THIS A BROWN DWARF OR AN EXOPLANET? NEW YOUNG SUB-STELLAR COMPANION IMAGED WITH THE VLT European Southern Observatory release 09/05

Page 5 SPACE EXPLORATION OVERHAUL: NEXT FIVE YEARS "CRITICAL" By Leonard David

Page 5 DIRECTOR JAMES CAMERON WORKS WITH NASA ON FUTURE MARS MISSION By John Kelly

Page 5 SURFING THE WAVELENGTHSBy Maggie Turnbull

Page 7 EXPERTS EXAMINE THREAD OF LIFE IN THE UNIVERSEBy Leonard David

Page 7 NEW METHOD COULD DETECT ALIEN SPACE STATIONSBy Tammy Plotner

Page 7 LIFE'S GREATEST INVENTIONSFrom New Scientist

Page 7 NASA TESTING HUMAN-ROBOT INTERACTIONS IN UTAH DESERTNASA/ARC release 05-22AR

Page 8 REVISED ASTEROID SCALE AIDS UNDERSTANDING OF IMPACT RISKBy Elizabeth A. Thomson

Page 9 FLYING A SCIENCE LAB TO MARS By Stephen Hart

Page 11 PERFECT SPOT FOUND FOR MOON BASE By Robert Roy Britt

Announcements

Page 11 SEE THE OLDEST THING ON EARTHBy Ryan J. Foley

Page 11 NASA MAY SILENCE VOYAGERS ON APRIL 15By Jeff Barbour

Mission Reports

Page 11 MARS GLOBAL SURVEYOR IMAGESNASA/JPL/MSSS release

CU STUDY SHOWS EARLY EARTH ATMOSPHERE HYDROGEN-RICH, FAVORABLE TO LIFE University of Colorado release6 April 2005

A new University of Colorado at Boulder study indicates Earth in its infancy probably had substantial quantities of hydrogen in its atmosphere, a surprising finding that may alter the way many scientists think about how life began on the planet. Published in the April 7 issue of Science Express, the online edition of Science Magazine, the study concludes traditional models estimating hydrogen escape from Earth's atmosphere several billions of years ago are flawed. The new study indicates up to 40 percent of the early atmosphere was hydrogen, implying a more favorable climate for the production of pre-biotic organic compounds like amino acids, and ultimately, life. The paper was authored by doctoral student Feng Tian, Professor Owen Toon and Research Associate Alexander Pavlov of CU-Boulder's Laboratory for Atmospheric and Space Physics with Hans De Sterck of the University of Waterloo. The study was supported by the NASA Institute of Astrobiology and NASA's Exobiology Program.

"I didn't expect this result when we began the study," said Tian, a doctoral student in CU-Boulder's Astrobiology Center at LASP and chief author of the paper. "If Earth's atmosphere was hydrogen-rich as we have shown, organic compounds could easily have been produced."

Scientists believe Earth was formed about 4.6 billion years ago, and geologic evidence indicates life may have begun on Earth roughly a billion years later.

"This study indicates that the carbon dioxide-rich, hydrogen-poor Mars and Venus-like model of Earth's early atmosphere that scientists have been working with for the last 25 years is incorrect," said Toon. In such atmospheres, organic molecules are not produced by photochemical reactions or electrical discharges.

Toon said the premise that early Earth had a CO2-dominated atmosphere long after its formation has caused many scientists to look for clues to the origin of life in hydrothermal vents in the sea, fresh-water hot springs or those delivered to Earth from space via meteorites or dust.

The team concluded that even if the atmospheric CO2 concentrations were large, the hydrogen concentrations would have been larger. "In that case, the

Marsbugs: The Electronic Astrobiology Newsletter, Volume 12, Number 13, 13 April 2005

production of organic compounds with the help of electrical discharge or photochemical reactions may have been efficient," said Toon.

Amino acids that likely formed from organic materials in the hydrogen-rich environment may have accumulated in the oceans or in bays, lakes and swamps, enhancing potential birthplaces for life, the team reported. The new study indicates the escape of hydrogen from Earth's early atmosphere was probably two orders of magnitude slower than scientists previously believed, said Tian. The lower escape rate is based in part on the new estimates for past temperatures in the highest reaches of Earth's atmosphere some 5,000 miles in altitude where it meets the space environment.

While previous calculations assumed Earth's temperature at the top of the atmosphere to be well over 1,500 degrees F several billion years ago, the new mathematical models show temperatures would have been twice as cool back then. The new calculations involve supersonic flows of gas escaping from Earth's upper atmosphere as a planetary wind, according to the study.

"There seems to have been a blind assumption for years that atmospheric hydrogen was escaping from Earth three or four billion years ago as efficiently as it is today," said Pavlov. "We show the escape was limited considerably back then by low temperatures in the upper atmosphere and the supply of energy from the sun."

Despite somewhat higher ultraviolet radiation levels from the sun in Earth's infancy, the escape rate of hydrogen would have remained low, Tian said. The escaping hydrogen would have been balanced by hydrogen being vented by Earth's volcanoes several billion years ago, making it a major component of the atmosphere.

Left: Stanley Miller's classic "primordial soup" experimental setup, with a simulated ocean, lightning and broth of hydrogen, methane, ammonia and water. Right: University of Chicago graduate student, Stanley Miller, 1953. Image credit: University of Chicago.

In 1953, University of Chicago graduate student Stanley Miller sent an electrical current through a chamber containing methane, ammonia, hydrogen and water, yielding amino acids, considered to be the building blocks of life. "I think this study makes the experiments by Miller and others relevant again," Toon said. "In this new scenario, organics can be produced efficiently in the early atmosphere, leading us back to the organic-rich soup-in-the-ocean concept."

In the new CU-Boulder scenario, it is a hydrogen and CO2-dominated atmosphere that leads to the production of organic molecules, not the methane and ammonia atmosphere used in Miller's experiment, Toon said. Tian and other team members said the research effort will continue. The duration of the hydrogen-rich atmosphere on early Earth still is unknown, they said.

Journal reference:F. Tian, O. B. Toon, A. A. Pavlov and H. De Sterck, 2005. A hydrogen-rich early Earth atmosphere. Published online April 7 2005; 10.1126/science.1106983 (Science Express Reports). http://www.sciencemag.org/cgi/content/abstract/1106983v1.

Contacts: Owen ToonPhone: 303-492-1534

Feng TianPhone: 303-492-2413

Alexander PavlovPhone: 303-492-4765

Jim ScottPhone: 303-492-3114

Read the original news release at http://www.colorado.edu/news/releases/2005/156.html.

An additional article on this subject is available at http://www.astrobio.net/news/article1515.html.

WHERE BACTERIA GET THEIR GENESBy Daniel StolteUniversity of Arizona release7 April 2005

Bacteria acquired up to 90 percent of their genetic material from distantly related bacteria species, according to new research from The University of Arizona in Tucson. The finding has important biomedical implications because such gene-swapping, or lateral gene transfer, is the way many pathogenic bacteria pick up antibiotic resistance or become more virulent.

"To maintain effective treatments and develop new antibiotics, it's important to monitor the rates and patterns of lateral gene transfer," said team member Howard Ochman, a UA professor of biochemistry and molecular biophysics and a member of UA's BIO5 Institute.

The research also solves a long-standing evolutionary puzzle. Many scientists have argued that drawing traditional family trees does not make sense for bacteria, because their genomes represent a mix of genetic material from their parental cells and from other species of bacteria. Ochman and his colleagues' work shows that bacterial lineages can still be traced by considering only the "traditional" forms of genetic inheritance. The widespread exchange of genes does not blur the line of descent because the acquired genes get lost from the genome at a later point or, if they do persist, the bacteria then transmit them to their offspring.

Being able to classify bacteria is crucial for medicine, Ochman said. "If you go to the doctor with strep throat he can be pretty certain that it's the result of an infection with a species of Streptococcus and can therefore prescribe an appropriate antibiotic. If you couldn't classify bacteria because they have genes from all over, doctors wouldn't be able to do this."

The research report is published in the current issue of PLoS Biology, available on http://www.plosbiology.org. Ochman's coauthors are Nancy Moran, UA Regents' Professor of ecology and evolutionary biology and BIO5 member, and Emmanuelle Lerat, now at Universite Claude Bernard (Lyon, France) and Vincent Daubin, now at the Centre National de la Recherche Scientifique (CNRS) in France. The research was funded by the Department of Energy and the National Science Foundation.

Lateral gene transfer, unique to the bacterial world, has long been recognized as common. But until now scientists did not know which of a bacterium's genes came from lateral gene transfer and which had been inherited from its parent. In their study, the scientists focused on the best-studied group of bacteria, the Gamma-Proteobacteria. It includes many human pathogens, including Salmonella, Shigella, pathogenic E. coli, and Pseudomonas.

Ochman's team compared the bacterial species by analyzing their genomic sequence data. The researchers then computed family trees, taking into account the acquired genes, and matched the trees to an established reference tree. For all genes, the match was about 95 percent. This showed that the widespread mechanism of lateral gene transfer does not interfere with the traditional approach of using family trees to infer relationships. Ochman's team found that only 205 genes of Gamma-Proteobacteria's approximately 7,205 genes are shared by all species. The vast majority of genes found in the group come from lateral gene transfer. "Most of these occur in one or a few species only," Ochman said. "But these are the genes that make bacteria different from each other."

Most commonly, genes are transmitted by bacteriophages, viruses that specifically hijack bacteria cells. Like tiny syringes, phages inject their own genetic material into the host cell, forcing it to produce new phages. During such an event, genes from the bacterial genome can be incorporated into the newly made phages. They inject their newly modified genetic load into other bacteria. This way, bacteriophages act as shuttles, taking up DNA from one bacterium and dumping it into another. Bacteria can also make contact by

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tiny connection tubes through which they exchange pieces of DNA. They can also take up genetic material from the environment.

Ochman thinks the team's findings will stir new research in bacterial evolution. "It should be exciting to see whether gene transfer has been so widespread in other groups of bacteria, too."

Lateral gene transfer (LGT) and genome evolution in γ-Proteobacteria. Only a small proportion of genes have been retained since the common ancestor of γ-proteobacteria (in red). Under the assumption that ancestral and contemporary genome sizes are similar, most of the genes present in this ancestral genome (in white) have been replaced by nonhomologous genes (yellow to green), usually via LGT from organisms outside of this clade. Once a new gene is acquired, its transmission follows vertical inheritance. The abundance of genes unique to a species (in blue) indicates that these bacteria (with the exception of the endosymbionts) constantly acquire new genes, most of which do not persist long-term within lineages. (Numbers of protein-coding genes, excluding those corresponding to known IS elements and phages, are in parentheses for each genome). From Lerat E, Daubin V, Ochman H, Moran NA (2005) Evolutionary Origins of Genomic Repertoires in Bacteria. PLoS Biol 3(5): e130.

Journal reference:E. Lerat, V. Daubin, H. Ochman and N. A. Moran, 2005. Evolutionary origins of genomic repertoires in bacteria. PLoS Biology, May 2005, Volume 3, Issue 5, e130. http://www.plosbiology.org.

Related Web sites:Howard Ochman, http://www.biochem.arizona.edu/dept/ppl/Profiles/ochman.htmNancy Moran, http://eebweb.arizona.edu/Faculty/Bios/moran.htmlBIO5 Institute, http://www.bio5.org

Contacts:Daniel Stolte, UA News ServicesPhone: 520-626-4407

Howard OchmanPhone: 520-626-8355E-mail: hochman@email.arizona.edu

Nancy MoranPhone: 520-621-3581E-mail: nmoran@email.arizona.edu

"BORN-AGAIN" STARS REVEAL HOW THE EARTH WAS CREATED University of Manchester release7 April 2005

Scientists at The University of Manchester have unveiled new research which shows how exploding stars may have helped to create the earth. The discovery was made during a unique research project examining how some dead stars re-ignite and come back to life. Professor Albert Zijlstra's study of Sakurai's Object—the only star which has been observed re-igniting in modern times—has led him to conclude that 5% of the carbon on earth may have been come from stardust expelled by stars exploding back to life.

"Up to 0.1% of the total mass of the star, which is equivalent to 300 times the mass of the earth, can be expelled when a star re-ignites," says Professor Zijlstra. "This discovery not only gives us a new understanding of where the natural material that made up the earth came from, but also leads us to believe that part of the carbon in the universe could have come from these events."

Radio/optical images of Sakurai's Object. The color image shows nebula ejected thousands of years ago. Contours indicate radio emissions. Inset is Hubble Space Telescope image showing the central part of the region with contours indicating radio emission. Image credit: Hajduk et al., NRAO/AUI/NSF, ESO, StSci, NASA.

Stars die when they have used up most of their hydrogen. For the Sun, this will happen in about 4.5 billion years. But some stars will experience a brief rebirth when their helium suddenly ignites, and the remaining hydrogen in their outer envelope is drawn into the helium shell. After the explosive re-ignition, the star will expand to giant proportions—expelling tons of carbon in the process—before rapidly burning out again.

"We expect that some 25% of all stars will experience such a re-ignition, but this is an extremely rare occurrence, and we will probably only see it happen once every hundred years or so", says Professor Zijlstra.

Left: Spectacular gas remnants from exploding star. Right: Our Milky Way galaxy is packed with 400 billion stars and perhaps even more planets. Image credits: NASA/Hubble.

Incredibly, the earth's formation was not the main focus of Professor Zijlstra's research, which sought to establish a better understanding of why Sakurai's Object had re-ignited. Computer simulations had predicted a series of events that would follow such a re-ignition, but the star didn't follow the script—events moved 100 times more quickly than the simulations predicted.

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"Sakurai's Object went through the first phases of this sequence in just a few years—100 times faster than we expected—so we had to revise our models. We've now produced a new theoretical model of how this process works, and the observations have provided the first evidence supporting our new model," Zijlstra said.

"It's important to understand this process. Sakurai's Object has ejected a large amount of carbon into space, both in the form of gas and dust grains. These will find their way into regions of space where new stars form, and the dust grains may become incorporated in new planets. Our results suggest this source for cosmic carbon may be far more important than previously suspected," Zijlstra added.

Zijlstra's findings will be presented in the April 8 issue of the prestigious journal, Science.

Journal references:M. Hajduk et al., 2005. The real-time stellar evolution of Sakurai's Object. Science, 308(5719):231-233. http://www.sciencemag.org/cgi/content/short/308/5719/231.M. Asplund, 2005. Enhanced: A stellar swan-song. Science, 308(5719):210-211. http://www.sciencemag.org/cgi/content/summary/308/5719/210.

Read the original news release at http://www.manchester.ac.uk/press/title,20449,en.htm.

An additional article on this subject is available at http://www.astrobio.net/news/article1518.html.

IS THIS A BROWN DWARF OR AN EXOPLANET? NEW YOUNG SUB-STELLAR COMPANION IMAGED WITH THE VLT European Southern Observatory release 09/057 April 2005

Since the discovery in 1995 of the first planet orbiting a normal star other than the Sun, there are now more than 150 candidates of these so-called exoplanets known. Most of them are detected by indirect methods, based either on variations of the radial velocity or the dimming of the star as the planet passes in front of it. Astronomers would, however, prefer to obtain a direct image of an exoplanet, allowing them to better characterize the object's physical nature. This is an exceedingly difficult task, as the planet is generally hidden in the "glare" of its host star.

ESO PR Photo 10a/05 shows the VLT NACO image, taken in the Ks-band, of GQ Lupi. The feeble point of light to the right of the star is the newly found cold companion. It is 250 times fainter than the star itself and it located 0.73 arcsecond west. At the distance of GQ Lupi, this corresponds to a distance of roughly 100 astronomical units. North is up and East is to the left.

To partly overcome this problem, astronomers study very young objects. Indeed, sub-stellar objects are much hotter and brighter when young and therefore can be more easily detected than older objects of similar mass.

Based on this approach, it might well be that last year's detection of a feeble speck of light next to the young brown dwarf 2M1207 by an international team of astronomers using the ESO Very Large Telescope is the long-sought bona-fide image of an exoplanet. A recent report based on data from the Hubble Space Telescope seems to confirm this result. The even more recent observations made with the Spitzer Space Telescope of the warm infrared glows of two previously detected "hot Jupiter" planets is another interesting result in this context. This wealth of new results, obtained in the time span of a few months, illustrates perfectly the dynamic of this field of research.

Now, a different team of astronomers [1] has possibly made another important breakthrough in this field by finding a tiny companion to a young star. Since several years these scientists have conducted a search for planets and low-mass objects, in particular around stars still in their formation process—so-called T-Tauri stars—using both the direct imaging and the radial velocity techniques. One of the objects on their list is GQ Lupi, a young T-Tauri star, located in the Lupus I (the Wolf) cloud, a region of star formation about 400 or 500 light-years away. The star GQ Lupi is apparently a very young object still surrounded by a disc, with an age between 100,000 and 2 million years.

The astronomers observed GQ Lupi on 25 June 2004 with the adaptive optics instrument NACO attached to Yepun, the fourth 8.2-m Unit Telescope of the Very Large Telescope located on top of Cerro Paranal (Chile). The instrument's adaptive optics (AO) overcomes the distortion induced by atmospheric turbulence, producing extremely sharp near-infrared images. As ESO PR Photo 10a/05 shows, the series of NACO exposures clearly reveal the presence of the tiny companion, located in the close vicinity of the star. This newly found object is only 0.7 arcsecond away, and would have been overlooked without the use of the adaptive optics capabilities of NACO.

At the distance of GQ Lupi, the separation between the star and its feeble companion is about 100 astronomical units (or 100 times the distance between the Sun and the Earth). This is roughly 2.5 times the distance between Pluto and the Sun. The companion, called GQ Lupi B or GQ Lupi b [2], is roughly 250 times fainter than GQ Lupi A as seen in this series of image. Further images obtained with NACO in August and September confirmed the presence and the position of this companion.

The astronomers then uncovered that the star had been previously observed by the Subaru telescope as well as by the Hubble Space Telescope. They retrieved the corresponding images from the data archives of these facilities for further analysis. The older images, taken in July 2002 and April 1999, respectively, also showed the presence of the companion, giving the astronomers the possibility of precisely measuring the position of the two objects over a period of several years. This in turn allowed them to determine if the stars move together in the sky—as should be expected if they are gravitationally bound together—or if the smaller object is only a background object, just aligned by chance.

From their measurements, the astronomers found that the separation between the two objects did not change over the five-year period covered by the observations (see ESO PR Photo 10b/05). For the scientists this is a clear proof that both objects are moving in the same direction in the sky.

"If the faint object would be a background object", says Ralph Neuhäuser of the University of Jena (Germany) and leader of the team, "we would see a change in separation as GQ Lup would be moving in the sky. From 1999 to 2004, the separation would have changed by 0.15 arcsec, while we are confident that the change is a least 20 times smaller."

To further probe the physical nature of the newly discovered object, the astronomers used NACO on the VLT to take a series of spectra. These showed the typical signature of a very cool object, in particular the presence of water and CO bands. Taking into account the infrared colours and the spectral data available, atmospheric model calculations point to a temperature between 1,600 and 2,500 degrees and a radius that is twice as large as Jupiter (see PR Photo 10c/05). According to this, GQ Lupi B is thus a cold and rather small object.

But what is the nature of this faint object? Is it a bona-fide exoplanet or is it a brown dwarf, those "failed" stars that are not massive enough to centrally produce major nuclear reactions? Although the borderline between the two is still a matter of debate, one way to distinguish between the two is by their mass (as this is also done between brown dwarfs and stars): (giant) planets are lighter than about 13 Jupiter-masses (the critical mass needed to ignite deuterium fusion), brown dwarfs are heavier.

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What about GQ Lupi b? Unfortunately, the new observations do not provide a direct estimate of the mass of the object. Thus the astronomers must rely on comparison with theoretical models of such objects. But this is not as easy as it sounds. If, as astronomers generally accept, GQ Lupi A and B formed simultaneously, the newly found object is very young. The problem is that for such very young objects, traditional theoretical models are probably not applicable. If they are used, however, they provide an estimate of the mass of the object that lies somewhere between 3 to 42 Jupiter-masses, i.e. encompassing both the planet and the brown dwarf domains.

ESO PR Photo 10c/05 shows the NACO spectrum of the companion of GQ Lupi (thick line, bottom) in the near-infrared (around the Ks-band at 2.2 microns). For comparison, the spectrum of a young M8 brown dwarf (top, in red) and of a L2 brown dwarf (second line, in brown) are shown. Also presented is the spectrum calculated using theoretical models for an object having a temperature of 2,000 degrees. This theoretical spectrum compares well with the observed one.

These early phases in brown dwarf and planet formation are essentially unknown territory for models. It is very difficult to model the early collapse of the gas clouds given the conditions around the forming parent star. One set of models, specifically tailored to model the very young objects, provide masses as low as one to two Jupiter-masses. But as Ralph Neuhäuser points out "these new models still need to be calibrated, before the mass of such companions can be determined confidently".

The astronomers also stress that from the comparison between their VLT/NACO spectra and the theoretical models of co-author Peter Hauschildt from Hamburg University (Germany), they arrive at the conclusion that the best fit is obtained for an object having roughly 2 Jupiter radii and 2 Jupiter masses. If this result holds, GQ Lupi b would thus be the youngest and lightest exoplanet to have been imaged.

Further observations are still required to precisely determine the nature of GQ Lupi B. If the two objects are indeed bound, then the smallest object will need more than 1,000 years to complete an orbit around its host star. This is of course too long to wait but the effect of the orbital motion might possibly be detectable—as a tiny change in the separation between the two objects—in a few years. The team therefore plans to perform regular observations of this object using NACO on the VLT, in order to detect this motion. No doubt that in the mean time, further progress on the theoretical side will be achieved and that many sensational discoveries in this field will be made.

Journal reference:The research presented in this ESO Press Release is published in a Letter to the Editor accepted for publication by Astronomy and Astrophysics ("Evidence for a co-moving sub-stellar companion of GQ Lup" by R. Neuhäuser et al.) and available in PDF form at http://www.edpsciences.org/articles/aa/pdf/forthpdf/aagj061_forth.pdf.

Notes:[1]: The team is composed of Ralph Neuhäuser, Günther Wuchterl, Markus Mugrauer, and Ana Bedalov (University of Jena, Germany), Eike Guenther (Thüringer Landessternwarte Tautenburg, Germany), and Peter Hauschildt (Hamburger Sternwarte, Germany). [2]: In the astronomical literature, the convention is to put capitals for stars member of multiple systems, but small letters for planets. If the companion to

GQ Lupi A turns out to be a planet, it would be called GQ Lupi b, while if it is a brown dwarf, it would be identified as GQ lupi B. Given the present uncertainty, we have therefore used both denominations in this press release, as did the authors in the original scientific paper.

Contact:Ralph Neuhäuser Astrophysikalisches Institut University of Jena, Germany Phone: +49 36 41 94 75 00 Email: rne@astro.uni-jena.de

Read the original news release at http://www.eso.org/outreach/press-rel/pr-2005/pr-09-05.html.

Ann additional article on this subject is available at http://www.astrobio.net/news/article1520.html.

SPACE EXPLORATION OVERHAUL: NEXT FIVE YEARS "CRITICAL" By Leonard DavidFrom Space.com8 April 2005

After decades of sending probes across the void of interplanetary space, officials are now reshaping how solar system exploration is accomplished. The renovation is due in large measure to the visionary Moon, Mars and beyond directive given to NASA by U.S. President George W. Bush just more than a year ago. While money and mandate are in a state of near-rendezvous, the melding of space science objectives with human exploration goals is still to be fully played out, as is the prospect of broader international collaboration.

"The scientific exploration agenda NASA has been pursuing for the past decade or so is bearing enormous fruit, providing key early inputs to how NASA implements the vision," said James Garvin, NASA Chief Scientist in Washington, DC. "Initial robotic steps in the vision implementation will inform and guide future decisions that will ultimately steer how human beings explore the Moon and Mars."

Read the full article at http://www.space.com/missionlaunches/050408_space_science.html.

DIRECTOR JAMES CAMERON WORKS WITH NASA ON FUTURE MARS MISSION By John KellyFrom Florida Today and Space.com9 February 2005

The maker of legendary movies Titanic, Aliens and The Terminator is no longer limiting his zest for extracurricular exploration to the depths of the ocean. Nowadays, James Cameron is spending more of his "spare" time involved in NASA's bid to send human explorers deeper into the solar system.

He's always been a space nut. He says he cried when, at 15 years old, he watched shuttle Columbia launch for the first time. He cried again the first time he saw—in person—a shuttle blast off from Kennedy Space Center, and felt the vibrations of the sound wave slam into his chest and move right through him. Now, however, he's not just dreaming and watching from the sidelines. He's trying to help.

Read the full article at http://www.space.com/entertainment/ft_cameron_mars_050209.html.

SURFING THE WAVELENGTHSBy Maggie TurnbullFrom Astrobiology Magazine11 April 2005

Maggie Turnbull, an astronomer with the Carnegie Institution, has spent many years thinking about what kind of stars could harbor Earth-like planets. Her database of potentially habitable star systems could be used as a target list for NASA's upcoming Terrestrial Planet Finder (TPF) mission. Turnbull presented a talk, "Remote Sensing of Life and Habitable Worlds: Habstars, Earthshine and TPF," at a NASA Forum for Astrobiology Research on March 14, 2005. This edited transcript of the lecture is part one of a four-part series.

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Left: Artist concept of star system, HD70642. Image credit: John Rowe animation. Right: Scene from a moon orbiting the extra-solar planet in orbit around the star HD70642. Image credit: David A. Hardy, astroart.org © pparc.ac.uk.

To what extent is the universe alive? As soon as we ask that question, a million more questions pop up: "What is life?" "How does life originate?" "Could life be originating on Earth now, and if not, why not?" "Where is life found?" "Can life spread between planets or even between stellar systems?" "If life can travel between stellar systems, do we have relatives among the stars?" "Are there other technological civilizations out there?"

Those are too many questions for me to try to answer right now, but I will address the question, "Are there habitable terrestrial planets orbiting nearby stars?" That immediately leads us to ask, "What is a habitable planet?" All life on Earth depends on the availability of liquid water, so I'll just say that a habitable planet is one that has liquid water on its surface.

So the habitable zone will be that location around a star where an Earth-like planet will be at the right temperature so that it will have liquid water on its surface. Around our sun, the habitable zone extends from about 0.7 AU out to about 1.5 AU. (1 AU is the distance between the Earth and the sun.) For other stars, we'll just scale that as the square root of the luminosity of the star.

The first mission objective of the Terrestrial Planet Finder is to hone in on the zone where a terrestrial planet could have liquid water on its surface, and directly image any terrestrial planets in that zone. We want to see these planets with our own eyes. We want to take a picture, and see a little dot. The goal is to image planets in a habitable zone that have at least half Earth's surface area. We want to be able to image planets somewhere between the size of Mars and Earth, or larger.

Earth as seen by the departing Voyager spacecraft: a tiny, pale blue dot. Image credit: NASA.

The second goal of TPF is to characterize the atmospheres of any planets we find for indicators of life. The third goal is to do comparative planetology, so that when we have a database of planetary systems in the solar neighborhood, we can ask questions like, "How common are terrestrial planets?" "How diverse are they?" "How common is it to have a habitable terrestrial planet?" "Is liquid water a common thing, or do most planets look like Venus or

Mars?" "Are terrestrial planets common at all, or is it more common to have massive eccentric Jupiters?"

Left: HD 28185 b was the first exoplanet discovered with a circular orbit within its star's habitable zone. Image credit: STScI Digitized Sky Survey. Right: Comparison of Mars, Venus and Earth in water bands, showing the clear presence of water on Earth uniquely. Saturn's moon Titan has perhaps the highest atmospheric content for methane with other primordial elements. Image credit: NASA Workshop, Pale Blue Dot.

The Terrestrial Planet Finder originally was envisioned as a mid-infrared mission, because it was thought that mid-infrared wavelengths would be the best way to search for extrasolar Earths around nearby stars. In the mid-infrared, planets emit their own light, while the light from the star is tailing off, so the contrast shown for the mid-infrared is better than in the optical.

At the shorter optical wavelengths, the Earth's spectrum mirrors the Sun—it's just reflecting sunlight. As we get into the mid-infrared, the Earth starts emitting its own light, because it has a temperature of 300 degrees Kelvin (80°F). That heat translates into light in the mid-infrared. So a planet's mid-infrared light can give us a handle on the temperature of the planet, and tell us if that temperature is right for liquid water at the surface.

In a universe brimming with stars, the search is on to discover whether life exists elsewhere. Image credit: NASA/STScI/ESA.

Also in the mid-infrared, we can see some exciting signatures, such as carbon dioxide, water, and ozone. Since ozone is a proxy for molecular oxygen, it's an indicator of life. Spectra in the infrared taken by the Galileo spacecraft of Mars, Earth, and Venus showed that the three planets look fairly similar. But Earth had two indicators of habitability and life, namely, water and ozone.

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The Earth is one-ten-billionth as bright as the sun in the optical. In the mid-infrared, it's only a factor of one million, so it's not quite as bad. But still, if you take the Earth-sun system, and put it at 10 parsecs distance—about 30 light years away—there will be an angular separation between the two of 100 milliarcseconds. That's very small. So even looking in the mid-infrared—with the planet being one millionth as bright as the sun at 100 milliarcseconds at 10 parsecs—that's not easy.

In order to do high resolution imaging in the mid-infrared, we need to have a very long baseline, which means we need to either have a huge telescope, or we need to somehow fly an interferometer in formation. That technology is more advanced than what we'll have over the next ten years.

So the first mission will be TPF-C, a coronagraph that is slated for launch in 2014, and it will operate at optical wavelengths. The key issue here is that we need to suppress the light of the star so that we can see the light of the planet—planets are very much fainter than the star.

For the optical, we don't have observations that are analogous to the Galileo infrared observations. We've got lots of satellite observations of Earth in the optical wavelengths, but the low-flying satellites only see a small footprint of ground at a time. We don't have satellite observations that have the whole spectrum of the visible Earth all summed up in one pixel.

So to get those spectra, we have to observe them from the ground. Luckily, we can do that by looking at the moon, by pointing our telescopes at where "Earthshine" lights up the dark portion of the thin crescent moon. The way this works is, the sun shines on the Earth, the Earth shines on the moon, and that light reflects off the moon and goes back to the Earth and into our telescope. The dark portion of the moon shows the spectrum of the whole Earth, all summed up together.

Sunlight reflecting off the bright crescent of the moon also goes into our telescope as we observe it on the ground. We just take our dark moon spectrum and divide it by our bright moon spectrum, and what we have left over is the spectrum of the Earth. In the Earth's optical spectrum, we see Rayleigh scattering in the blue part of the spectra—we're seeing the blue sky of our planet. We also have signs of oxygen, ozone, and water. We may even be able to see signs of vegetation in the optical.

The interesting thing about observing the Earth in the optical is that you can see all the way through Earth's atmosphere to the ground. The light that reflects back contains the spectrum of whatever is on the ground of that planet, whether it's oceans, or soil, or plants. And plants happen to have a very distinctive spectrum that could be observable even across stellar distances.

All land plants have pretty much the same spectral signature—they're very dark in the optical, where 10 percent of the light that strikes them gets reflected. For the most part, in the optical, they absorb just about all of the photons that fall on them, which makes them good photosynthesizers. They become strongly reflective in the near-infrared, where they reflect 70 percent of the light that falls on them. This "vegetation edge" is a distinctive spectral feature that allows satellites to map the health, density and even different species of plants on Earth.

Now, you could ask how relevant this is to the search for life elsewhere. Do we really expect Earth-like plants to be on other terrestrial planets? It's not reasonable to expect that, but life does have a way of exploiting whatever energy source is available. So life on the surface of a planet should be expected to be photosynthetic. It's going to absorb very strongly in some wavelength range where the atmosphere of the planet is transparent and where the star is emitting a lot of energy.

Is it just a coincidence that plants on Earth become strongly reflecting in the infrared? Or is that useful to the plant biologically, for instance, for cooling purposes? If it is biologically advantageous to reject photons that are not energetically useful rather than absorbing them, and to strongly absorb those wavelength ranges where you can do something with the energy, then we should not be surprised if photosynthetic life on other planets also has a strong spectral "edge" feature.

Read the original article at http://www.astrobio.net/news/article1519.html.

EXPERTS EXAMINE THREAD OF LIFE IN THE UNIVERSEBy Leonard DavidFrom Space.com11 April 2005

Consider it nothing short of the cosmic quest for all time: Understanding the origin, evolution, distribution, and fate of life on Earth and in the Universe. That’s a tall order, but within the sights of experts gathering here this week to take part in the 2005 Biennial Meeting of the NASA Astrobiology Institute. From the formation and evolution of habitable worlds to the origins of life, extra-solar planets, and future exploration technologies and strategies—dedicated scientists are tackling big questions in a big universe.

Read the full article at http://www.space.com/searchforlife/050411_astrobio_nasa.html.

NEW METHOD COULD DETECT ALIEN SPACE STATIONSBy Tammy PlotnerFrom Universe Today11 April 2005

Since the beginning of astronomical observation, science has been viewing light on a curve. In a galaxy filled with thousands of eclipsing binary stars, we've refined our skills by measuring the brightness or intensity of so-called variable star as a function of time. The result is known as a "light curve". Through this type of study, we've discovered size, distance and orbital speed of stellar bodies and refined our ability to detect planetary bodies orbiting distant suns. Here on Earth, most of the time it's impossible for us to resolve such small objects even with the most powerful of telescopes, because their size is less than one pixel in the detector. But new research should let us determine the shape of an object, like a ringed planet, or an orbiting alien space station.

Read the full article at http://www.universetoday.com/am/publish/alien_space_stations.html.

LIFE'S GREATEST INVENTIONSFrom New Scientist11 April 2005

Evolution's methods are blind, brutish and aimless, yet it has fashioned some of the most exquisite machines in the known universe. And every now and then, it stumbles across a truly stunning innovation that rewrites the rules of life. From the eye and the brain to language and sex, New Scientist reveals the Top Ten at http://www.newscientist.com/channel/life/mg18624941.700.

NASA TESTING HUMAN-ROBOT INTERACTIONS IN UTAH DESERTNASA/ARC release 05-22AR12 April 2005

Two NASA robots and two geologists are now simulating an expedition to another planet during a field test expected to continue until April 15 in Utah's Southeast Desert, near Hanksville. During the ongoing "Mobile Agents Project", NASA engineers are working to improve human-robot interactions to help NASA accomplish its Vision for Space Exploration to return to the moon and venture to Mars. The wheeled robots are attempting to help the astronaut team to maintain connection with a wireless computer network.

"As you look at NASA's exploration vision to return to the moon and go on to Mars, human-robotic cooperation will be vital to achieve that vision," said Eugene Tu, deputy director for the Exploration Technology Directorate at NASA Ames Research Center in California's Silicon Valley.

"One of our biggest problems is to break out of preconceived notions rooted in science fiction or existing robotic technology," said Bill Clancey, principal investigator for the Mobile Agent project. "By building and testing prototypes, we can test design concepts."

During the field exercise, the researchers' objective is to develop ways to enable robots to take the initiative to work together to help a team of astronauts. Scientists and engineers from NASA Ames and NASA Johnson Space Center, Houston, are taking part in the test. Prototype "Extravehicular Activity (EVA) Robotic Assistants", developed at NASA Johnson, will follow

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geologists and respond to voice commands at the Mars Society's Mars Desert Research Station.

A group huddles around [the robot] Thibodeaux in the wind; explanations provided by Bill Vreugde and Ed Herrera. Image credit: Mars Society.

According to NASA scientists, human-robotic interactions can best be improved using in-situ experiments, during which people and robots cooperate to do research. Scientists plan to examine the interacting constraints of landscape, distance, work coordination and other factors to suggest what new tools and methods are needed to refine existing technology. This process will bring together the remote science team, mission support, the habitat and its crew, robots, computer networks and astronauts to simulate planetary surface exploration.

A team that includes about 20 people has placed equipment in and around the Mars Desert Research Station. Team members are using prototype tools, including a wireless computer network, the voice-commanded robots and voice-commanded mission control communication services that partly automate the role of the kind of communications used during the Apollo missions to the moon in the late 1960s and early 1970s.

Mobile Agents team plans first reconnaissance "EVA" for Boudreaux, the robot. Image credit: Mars Society.

Researchers are continuing to conduct a series of human-robot simulated geology missions to scout new terrain during multiple days. These simulations also involve the remote science team. Scientists are making audio and video recordings of the activities. Researchers later will evaluate the data to learn about human-robot interactions including voice commands and work preferences. From analysis of the recordings and other data, investigators can assess equipment, software and procedures. Scientists can then write new requirements and specifications to improve human-robot interactions and cooperation.

Publication-size images are available at http://www.marssociety.org/MDRS/fs04/.

Contacts:John BluckNASA Ames Research Center, Moffett Field, CAPhone: 650-604-5026 or 604-9000E-mail: jbluck@mail.arc.nasa.gov

Kelly HumphriesNASA Johnson Space Center, Houston, TXPhone: 281-483-5111

REVISED ASTEROID SCALE AIDS UNDERSTANDING OF IMPACT RISKBy Elizabeth A. ThomsonMassachusetts Institute of Technology release12 April 2005

Astronomers led by an MIT professor have revised the scale used to assess the threat of asteroids and comets colliding with Earth to better communicate those risks with the public. The overall goal is to provide easy-to-understand information to assuage concerns about a potential doomsday collision with our planet. The Torino scale, a risk-assessment system similar to the Richter scale used for earthquakes, was adopted by a working group of the International Astronomical Union (IAU) in 1999 at a meeting in Torino, Italy. On the scale, zero means virtually no chance of collision, while 10 means certain global catastrophe.

"The idea was to create a simple system conveying clear, consistent information about near-Earth objects [NEOs]," or asteroids and comets that appear to be heading toward the planet, said Richard Binzel, a professor in MIT's Department of Earth, Atmospheric and Planetary Sciences and the creator of the scale. Some critics, however, said that the original Torino scale was actually scaring people, "the opposite of what was intended," said Binzel, hence the revisions.

"For a newly discovered NEO, the revised scale still ranks the impact hazard from 0 to 10, and the calculations that determine the hazard level are still exactly the same," Binzel said. The difference is that the wording for each category now better describes the attention or response merited for each.

For example, in the original scale NEOs of level 2-4 were described as "meriting concern." The revised scale describes objects with those rankings as "meriting attention by astronomers"—not necessarily the public.

Equally important in the revisions, says Binzel, "is the emphasis on how continued tracking of an object is almost always likely to reduce the hazard level to 0, once sufficient data are obtained." The general process of classifying NEO hazards is roughly analogous to hurricane forecasting. Predictions of a storm's path are updated as more and more tracking data are collected.

According to Dr. Donald K. Yeomans, manager of NASA's Near Earth Object Program Office, "The revisions in the Torino Scale should go a long way toward assuring the public that while we cannot always immediately rule out Earth impacts for recently discovered near-Earth objects, additional observations will almost certainly allow us to do so."

The highest Torino level ever given an asteroid was a 4 last December, with a 2 percent chance of hitting Earth in 2029. And after extended tracking of the asteroid's orbit, it was reclassified to level 1, effectively removing any chance of collision, "the outcome emphasized by level 4 as being most likely," Binzel said.

"It is just a matter of the scale becoming more well known and understood. Just as there is little or no reason for public concern over a magnitude 3 earthquake, there is little cause for public attention for NEO close encounters having low values on the Torino scale." He notes that an object must reach level 8 on the scale before there is a certainty of an impact capable of causing even localized destruction.

The Torino scale was developed because astronomers are spotting more and more NEOs through projects like the Lincoln Near Earth Asteroid Research project at MIT's Lincoln Laboratory. "There's no increase in the number of

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asteroids out there or how frequently they encounter our planet. What's changed is our awareness of them," Binzel notes.

As a result, astronomers debated whether they should keep potential NEO collisions secret or "be completely open with what we know when we know it," Binzel said. The IAU working group, of which Binzel is secretary, resoundingly decided on the latter.

The revised wording of the scale was published last fall in a chapter of Mitigation of Hazardous Comets and Asteroids (Cambridge University Press). The revisions were undertaken through consultation with astronomers worldwide for nearly a year before being published.

Binzel concludes that "the chance of something hitting the Earth and having a major impact is very unlikely. But although unlikely, it is still not impossible. The only way to be certain of no asteroid impacts in the forecast is to keep looking."

For more information on the revised Torino scale, go to http://neo.jpl.nasa.gov/torino_scale.html. A version of this article appeared in the April 13, 2005 issue of MIT Tech Talk (Volume 49, Number 24, http://web.mit.edu/newsoffice/techtalk-info.html).  Contact:Elizabeth A. Thomson, MIT News OfficePhone: 617-258-5402E-mail: thomson@mit.edu

Read the original news release at http://web.mit.edu/newsoffice/2005/torino.html.

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

FLYING A SCIENCE LAB TO MARS By Stephen HartFrom Astrobiology Magazine13 April 2005

Even before the Mars Science Lander (MSL) touches down descending from its hovering mother ship like a baby spider from an egg case the first of a slew of cameras will have started recording, capturing and storing high-resolution video of the landing area. The MSL landing will represent a first, says Frank Palluconi, MSL project scientist. After entering the Mars atmosphere like Viking and MER but with a potential landing zone about one fourth the size he says, MSL will show its stuff. "It completes the descent down to the ten-meter [33-foot] level, or so, where the descent vehicle hovers, and it lowers the rover on a tether down to the surface. By that time, the rover has erected its wheels, so it lands on its mobility system. And then the tether is cut and the descent stage flies away and is no longer used. It crashes."

In addition to the obvious advantages of such a soft landing, hovering and the tether drop are possible to model mathematically, unlike the airbag landing the MER vehicles used. Tethered descent is also scalable, Palluconi says, whereas the much smaller MERs were pushing the envelope of the airbag system's capability.

Left: Artist conception of Mars long-range science laboratory. Image credit: NASA/JPL. Right: Sundown on Mars, Pathfinder mission. Image credit: NASA/JPL.

Eyes on Mars

Shooting will begin as soon as the heat shield drops from the MSL descent stage. The Mars Descent Imager will take video in megapixel resolution, comparable to modern consumer digital video cameras. Aimed straight down, this camera will provide a spider's eye view of the landing area a very wide angle at first and continue shooting until the rover touches down on Mars.

Landing videos will be transmitted to Earth by the rover when it becomes fully functional. This visual information, showing the landing area and its surroundings in fine detail, along with the fact that the rover will land on its wheels no tricky navigation off of a landing vehicle needed will allow project scientists to begin working the rover much sooner.

Once the rover's mast rises and all systems are go, the real work will begin. As with MER, a mast-mounted, two-eyed camera system will feature prominently. The MastCam, like the descent imager and an arm-mounted close-up camera, is being designed and built by Malin Space Science Systems in San Diego, CA. All three rely on similar full-color, high-resolution subsystems. MastCam takes the basic setup found on the MERs twin cameras that will allow scientists to assemble 3D images and refines it considerably. MastCam has twin 10x optical zoom lenses, the same power as found in high-end consumer digital cameras on Earth. This will allow the camera to take not only wide-angle panoramas but also zoom in and focus on fist-sized rocks a kilometer (0.6 miles) away.

MastCam also shoots high definition video, a first for Mars. Both stills and video will be captured in full color, just like with earthbound digital cameras. In addition, MastCam will use a variety of specialized filters. Several members of the Malin Space Science Systems scientific team contributed to the various camera designs, including director James Cameron (Titanic, The Abyss, Aliens), a co-investigator on the MastCam science team.

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Schematic of major mission events during entry, descent and landing. Image credit: NASA/JPL/Cornell University/ Dan Maas.

Photograph, vaporize, analyze

The MSL mast will also hold a unique hybrid optical instrument, never before flown to Mars. Called the ChemCam, this telescopic tool takes close-ups at a distance with a field of view of about 30 cm (1 foot) at ten meters (33 feet) distance. But that's just the first step for ChemCam. In step two eerily reminiscent of the heat rays described in War of the Worlds a powerful laser will focus through the same telescope at the target. The laser can heat a spot about a millimeter (0.04 inches) in diameter to nearly ten thousand degrees Celsius (18 thousand degrees Fahrenheit). The heat blows away dust, breaks off molecules, breaks up the molecules and even breaks apart atoms in the rocky target.

Empty nest view back to landing petal from the mobile Opportunity rover, which has ventured to the crater's rim. Image credit: NASA/JPL.

As a result, the target emits a spark of light. ChemCam can analyze the spark's spectrum, identifying what elements carbon or silicon, for example the target contained. Called Laser-Induced Breakdown Spectroscopy, or LIBS, this technique is widely used on Earth but will be a first for Mars, says Roger C. Wiens, a planetary scientist at Los Alamos National Laboratory and the principal investigator on the ChemCam project. "LIBS is being used in a number of facets on earth. For example, a company that makes aluminum uses it to check the composition of their aluminum alloy in the molten state."

Going into space is a different story. Seven years in the making, ChemCam will make MSL much faster than MER at choosing targets, Wiens says. "The Opportunity rover landed in a small crater and here in front of us sat a rock outcrop, which is the first one we had seen on Mars up close and personal. And it was less than ten meters away. [With the ChemCam] we could have immediately analyzed that rock before actually even driving the rover off the pad, and told them that here sits a sedimentary rock outcrop right in front of you. Instead, it took a number of days, and they drove up to the rock and actually sampled it with the contact instruments before they really determined that it was a sedimentary rock outcrop." With its long optical reach, ChemCam can analyze objects out of reach of the rover's mechanical arm, even overhead.

In addition, ChemCam will be able to do some chemical analysis of small parts of rock samples, before they are crushed and transported to MSL's internal analytical instruments.

"I think this instrument is going to see a lot of use," Wiens says, "because we can take a lot of data rapidly. So one of the great things is that we can get a much larger database of rock samples than some of the in situ techniques. I think it's going to be an exciting instrument to build and fly."

Palluconi sees MSL as an intermediary step between MER and the direct search for life on Mars. "I would regard MSL as being kind of a transition mission between the more conventional aspects of planetary exploration, which involve geology and geophysics and, in the case of Mars because of its atmosphere, the climate and weather to ones in the future which will make direct searches for life. So the overall objective of MSL is to make a habitability assessment of the area that the vehicle lands in on Mars."

The near future

Small scout landers are one consideration for future "scout" missions. The mission has two goals. One is to study the geologic history of water, the key to unlocking the story of past climate change. Two is to search for evidence of a habitable zone that may exist in the ice-soil boundary, the "biological paydirt." Image credit: NASA JPL.

Because NASA decided only in December 2004, which of many scientific instruments proposed for MSL will actually fly, all of the scientists whose projects were chosen are scrambling to put the finishing touches on their instruments. "The mission is in phase A, which is a definition phase, so it's really the earliest formal phase of the mission," Palluconi says. "Right now the principle work on the science side is figuring out where to place the instruments on the rover, how to meet their thermal needs, how to ensure that they have the fields of view they need and that their other requirements are met. Of course, the vehicle itself is being designed at the same time and the design is being refined. So there's quite a bit of work to do and we're probably just about a year away from the preliminary design review, which on the 2009 launch schedule would occur next February."

Some aspects of the Mars Science Laboratory remain up in the air. Many of the MSL scientific instruments require plenty of power. The proposed source of that power, a radioisotope power supply, requires presidential approval, which lies in the future. And in March 2005, NASA began considering the possibility of flying two MSL rovers in 2011 instead of one in 2009.

Mars Odyssey recently detected water ice near the surface in the high latitudes, and in 2007 the Phoenix Mars Lander will investigate those regions. This August, the Mars Reconnaissance Orbiter will be launched. What it

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discovers will determine the fate of the Mars Science Laboratory, which is scheduled for launch in 2009.

In this artist rendition, the Phoenix lander is shown on the arctic plains of Mars just as it has begun to dig a trench through the upper soil layer. The polar water ice cap is shown in the far distance. This rendition of the Phoenix lander was created by artist Corby Waste of the Jet Propulsion Laboratory.

Read the original article at http://www.astrobio.net/news/article1521.html.

PERFECT SPOT FOUND FOR MOON BASE By Robert Roy BrittFrom Space.com13 April 2005

Researchers have identified what may be the perfect place for a Moon base, a crater rim near the lunar north pole that's in near-constant sunlight yet not far from suspected stores of water ice. Permanently sunlit areas would provide crucial solar energy for any future Moon settlement, a goal for NASA outlined last year by President George W. Bush. Such sites would also have resort-like temperatures compared with other lunar locations that fluctuate between blistering heat and unfathomable cold.

Equally important, in the permanently shadowed depths of craters around the lunar north pole, water ice may lurk, according to previous but unconfirmed observations. Melted, it would be vital for drinking. Broken into hydrogen and oxygen, the water could provide breathable air and be used to make rocket fuel for a trip to Mars. That fits in neatly with the White House vision of using the Moon as a stepping stone to Mars.

Read the full article at http://www.space.com/scienceastronomy/050413_moon_perfect.html.

SEE THE OLDEST THING ON EARTHBy Ryan J. FoleyFrom Associated Press and LiveScience.com9 April 2005

A tiny speck of zircon crystal that is barely visible to the eye is believed to be the oldest known piece of Earth at about 4.4 billion years old. For the first time ever, the public will have a chance to see the particle Saturday at the University of Wisconsin-Madison, where researchers in 2001 made the breakthrough discovery that the early Earth was much cooler than previously believed based on analysis of the crystal.

To create buzz about an otherwise arcane subject, the university is planning a daylong celebration of the ancient stone—capped with "The Rock Concert" by jazz musicians who composed music to try to answer the question: "What does 4.4 billion years old sound like?"

Read the full article at http://www.livescience.com/othernews/ap_050409_oldest_thing.html.

NASA MAY SILENCE VOYAGERS ON APRIL 15By Jeff BarbourFrom Universe Today12 April 2005

Today NASA has 55 active mission control teams monitoring ongoing spacecraft and station missions—13 associated with missions extended beyond original planning. Soon there may be seven less. By October of this year, we could be turning a deaf ear to data collected by one of the most successful NASA programs of all times. For even as Voyager 1 and 2 are poised to enter the interstellar realm, budget-minders in our nation's capital may have already sealed the fate on a pair of craft that could provide important information about our solar system—and beyond—for the next 15 years.

...If you are an American citizen, please call, write, e-mail, or hand-deliver a message to your congressional representatives. Tell them that the last word sent by Voyager I and Voyager II shall not go unheard. Tell them that humanity must not orphan its children—be they human, or technological. Tell them that long-after some boondoggle project funded by taxpayer dollars in support of parochial interests has fallen by the way-side, Voyager I and II will continue to be our emissaries to the Universe. And if you are a World citizen please petition your local government to speak plainly to the leadership of the United States telling them that the entire world has entrusted its hearts and minds to the continued expansion of humankind's presence in the Cosmos. Voyager 1 and Voyager 2 are on a mission for us all.

Read the full article at http://www.universetoday.com/am/publish/nasa_silence_voyagers.html.

MARS GLOBAL SURVEYOR IMAGESNASA/JPL/MSSS release31 March - 6 April 2005

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

Crater with Windstreak (Released 31 March 2005)http://www.msss.com/mars_images/moc/2005/03/31/

Northern Bands (Released 01 April 2005)http://www.msss.com/mars_images/moc/2005/04/01/

Crater Streaks (Released 02 April 2005)http://www.msss.com/mars_images/moc/2005/04/02/

Buttes near Meridiani (Released 03 April 2005)http://www.msss.com/mars_images/moc/2005/04/03/

Xanthe Valley (Released 04 April 2005)http://www.msss.com/mars_images/moc/2005/04/04/

Mars at Ls 193 Degrees (Released 05 April 2005)http://www.msss.com/mars_images/moc/2005/04/05/

Hephaestus Troughs (Released 06 April 2005)http://www.msss.com/mars_images/moc/2005/04/06/

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.

End Marsbugs, Volume 12, Number 13.

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