Marsbugs: The Electronic Astrobiology NewsletterVolume 12, Number 19, 7 June 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 2 SIGNIFICANT RUNOFF ON EARLY MARS IDENTIFIED IN RIVER CHANNELS BY NATIONAL AIR AND SPACE MUSEUM GEOLOGISTSNational Air and Space Museum release

Page 2 TOP 10 WAYS TO DESTROY EARTHBy Sam Hughs

Page 3 TITAN'S FACE LIFTEDBy Leslie Mullen

Page 4 NEW UNDERWATER VOLCANO FOUND NEAR SAMOAWoods Hole Oceanographic Institute release

Page 5 EXTRATERRESTRIAL: IMAGINING OTHER WORLDSBy Edna DeVore

Page 5 APPROACHING MARSBy Tony Phillips

Page 6 MARS: WINDOWS ON THE WORLDBy Joy Crisp

Page 8 BOMBING THE COMETFrom Astrobiology Magazine

Page 8 MOST AMERICANS BELIEVE ALIEN LIFE IS POSSIBLE, STUDY SHOWS By Tariq Malik

Page 8 SPIRIT, THE PROBLEM CHILDBy Joy Crisp

Page 9 COMET PUT ON LIST OF POTENTIAL EARTH IMPACTORSFrom New Scientist

Page 9 FUNDING FOR MOON, MARS PROJECTS PROMISEDBy Pam Easton

Page 9 SCRIPPS-LED GLOBAL OCEAN WARMING RESEARCH PAPER PUBLISHED IN SCIENCE EXPRESSScripps Institution of Oceanography release

Page 10 THE CENTER FOR THE STUDY OF LIFE IN THE UNIVERSEBy Frank Drake

Page 10 NASA SCIENTISTS CONFIRM LIQUID WATER ON EARLY EARTHNASA/ARC release 05-35

Page 10 NASA NAPSBy Patrick L. Barry and Tony Phillips

Page 11 DRIVING ON THE ROADMAPFrom Astrobiology Magazine

Page 12 OPPORTUNITY'S ESCAPE FROM DUNEBy Joy Crisp

Announcements

Page 13 GRIFFIN SUPPORTS ISRUMars Society release

Page 13 BOOK PREVIEW: SEEDING THE UNIVERSE WITH LIFE—SECURING OUR COSMOLOGICAL FUTURE By Michael Mautner

Page 14 ABSTRACT DEADLINE EXTENDED FOR MARS SOCIETY CONVENTIONMars Society release

Mission Reports

Page 14 CASSINI UPDATESMultiple agencies' releases

Page 18 NASA'S SPACE EYES FOCUS ON DEEP IMPACT TARGET NASA release 05-139

Page 19 HOW TO WATCH JULY 4 COMET IMPACTBy Joe Rao

Page 19 MER UPDATESNASA/JPL releases

Page 20 MARS EXPRESS: ANCIENT FLOODS ON MARSESA release

Page 22 MARS GLOBAL SURVEYOR IMAGESNASA/JPL/MSSS releases

Page 22 MARS ODYSSEY THEMIS IMAGESNASA/JPL/ASU releases

Page 22 NASA'S PHOENIX MARS MISSION BEGINS LAUNCH PREPARATIONSNASA release 05-141

Marsbugs: The Electronic Astrobiology Newsletter, Volume 12, Number 19, 7 June 2005

SIGNIFICANT RUNOFF ON EARLY MARS IDENTIFIED IN RIVER CHANNELS BY NATIONAL AIR AND SPACE MUSEUM GEOLOGISTSNational Air and Space Museum release20 May 2005

Mars is now a cold, dry desert, but robotic satellites and rovers have returned new evidence of a warmer and wetter climate more than 3.5 billion years ago, when conditions may have been more favorable for life. Geologists at the Smithsonian National Air and Space Museum's Center for Earth and Planetary Studies, working with colleagues at the University of Virginia, have discovered 21 river channels in the dry martian valleys, which provide new clues to this ancient climate. The researchers have determined that martian rivers were about the same size as their counterparts on Earth, suggesting similar amounts of runoff from thunderstorms or rapid snowmelt. The findings will appear in the June issue of the journal Geology.

The highland valley networks are perhaps the most compelling evidence for widespread runoff on Mars more than 3.5 billion years ago, but until recently we had no means of estimating the size of the rivers that carved these valleys. New higher-resolution orbital imaging has revealed at least 21 late-stage channels within valley networks, which we use to estimate river discharges and determine water sources. We find that channel width and associated formative discharge are comparable to terrestrial valley networks of similar area and relief. For 15 narrow channels in basin-filling valley networks, likely episodic runoff up to centimeters per day and first-order formative discharges of ~300-3,000 m3/s are similar to terrestrial floods supplied by precipitation. Geothermal melting of ground ice would produce discharges ~100 times smaller per unit area and would require pulsed outbursts to form the channels. In four large valleys with few tributaries, wider channels may represent large subsurface outflows or paleolake overflows, as these four channels originate at breached basin divides and/or near source regions for the catastrophic outflow channels.

Until the discovery of channels, scientists could not determine the amount of water that had flowed through these valleys. As lead author Ross Irwin, museum geologist, explained, "We have thought for some time that it likely rained or snowed on early Mars, but until we found the river channels we had no idea whether we were dealing with drizzle or storms." Co-authors Robert Craddock, another National Air and Space Museum geologist, and Alan Howard of the University of Virginia made a detailed "Case for Rainfall on a Warm, Wet Early Mars" in a 2002 paper.

Larger, periodic floods carve wider river channels, so by measuring the width of a channel, geologists can estimate the size of the flood that carved it. To explain the width of the martian channels, some watersheds likely received an inch or more of rain per day during storms, or more than 10 inches of melted snow on particularly warm days. Larger watersheds gave rise to larger river channels, as they do on Earth. Even using a conservative method to estimate the amount of water discharged through the rivers, the martian rivers still matched their terrestrial counterparts in terms of the volume of water per second during these ancient episodes of flow.

Previously, only eight river channels had been found in martian valleys, two of these by Irwin and Howard in 2002. The new discoveries were made using the THEMIS camera on the Mars Odyssey spacecraft that is currently in orbit around Mars. During the 3.5 billion years since water flowed in these channels, the valley floors have become partly filled by wind-blown sand and debris from meteorite impacts, so the channels are exposed along only part of their floors.

The martian river channels do not appear to have been active nearly as long as terrestrial rivers have however. "If it rained this hard every day throughout the many millions of years that runoff occurred, Mars would be far more heavily eroded than it is," Irwin said. "It seems more likely that Mars was wet at times with drier intervals in between." Mars may have always been a desert, but like the desert in the western United States, water appears to have flowed abundantly at least part of the time.

The Center for Earth and Planetary Studies is the scientific research unit within the Collections and Research Department of the Smithsonian Institution's National Air and Space Museum. The Center's scientists perform original research and outreach activities on topics covering planetary science, terrestrial geophysics and the remote sensing of environmental change.

Additional information is available on the NASM Mars Page at http://www.nasm.si.edu/research/ceps/research/mars/mars.cfm.

Journal reference:Rossman P. Irwin III, Robert A. Craddock, and Alan D. Howard, 2005. Interior channels in martian valley networks: discharge and runoff production. Geology, 33(6):489-492, http://www.gsajournals.org/gsaonline/?request=get-abstract&doi=10.1130%2FG21333.1

Read the original news release at http://www.nasm.si.edu/events/pressroom/releaseDetail.cfm?releaseID=134.

An additional article on this subject is available at http://www.spacedaily.com/news/mars-water-science-05h.html.

TOP 10 WAYS TO DESTROY EARTHBy Sam HughsFrom LiveScience.com25 May 2005

Destroying the Earth is harder than you may have been led to believe. You've seen the action movies where the bad guy threatens to destroy the Earth. You've heard people on the news claiming that the next nuclear war or cutting down rainforests or persisting in releasing hideous quantities of pollution into the atmosphere threatens to end the world.

Fools! The Earth was built to last. It is a 4,550,000,000-year-old, 5,973,600,000,000,000,000,000-ton ball of iron. It has taken more devastating asteroid hits in its lifetime than you've had hot dinners, and lo, it still orbits merrily.

Read the full article at http://www.livescience.com/technology/destroy_earth_mp.html.

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TITAN'S FACE LIFTEDBy Leslie MullenFrom Astrobiology Magazine25 May 2005

Thanks to a thick veil of orange smog, the surface of Titan has always been bathed in hazy uncertainty. Our view of Titan sharpened with the arrival of the Cassini spacecraft, which has been performing a slow dance through Saturn's system since June of 2004. By peeking through Titan's hydrocarbon shroud, Cassini has discovered what may be two large impact craters. Impact craters are the birthday candles of a planet's surface. A heavily cratered body like our Moon indicates a long-dead world, a place where not much happens to disturb the surface. An active planet that is constantly changing, such as the Earth, has far fewer impact craters visible on its face.

The geological or atmospheric activity of a world may be related to its prospects for life. The geologically inert, airless Moon is not thought to be capable of sustaining life as we know it. Whereas the Earth, with its weather, erosion, volcanism, and tectonic burial and uplift, has energy to spare, and life thrives in part because of this energy.

Left: Titan's craters help date the age of the surface. Right: Titan's strange ring. Image credit: NASA/JPL.

Titan may be another place in the solar system where life could gain a foothold. Although Titan is very cold—the average surface temperature is about 94 degrees Kelvin (minus 291 Fahrenheit)—it does have a thick atmosphere full of churning chemical reactions. Titan also may have ice volcanoes erupting on the surface, places that could potentially provide energetic havens for at least single-celled life.

Robert Nelson of NASA's Jet Propulsion Laboratory says that Titan was long thought to be the fresh-faced ingénue of the solar system, with a dynamic weather system that kept the surface even younger than Earth's. "The Titan model that we had been working with had thunderstorms of methane and ethane, with oceans and winds all over," says Nelson. "But Titan seems to be a lot more mild and benign then we had previously thought."

The proposed oceans of liquid hydrocarbons have not been found. And while images taken by the Huygens probe show river channels that may have formed as a result of methane rain showers, it is not known how often such storms occur, or even if they occur at all. Scientists do think that chemical reactions in Titan's atmosphere result in a nearly continuous snowfall of dark organic sludge. Ralph Lorenz of the Lunar and Planetary Lab at the University of Arizona notes that, if this sludge has been falling over the age of the solar system, it could be several hundred meters deep by now. Such an accumulation could hide many surface features, although craters deeper than a kilometer (or mountains taller than a kilometer) should still be visible.

Left: Close view of Titan from Huygens probe. Right: Icy pebbles on Titan. Image credit: ESA.

Small impact craters aren't seen in the Cassini images, but their absence is probably not due to burial. Instead, Titan's thick atmosphere causes smaller

meteorites to burn up before they can reach the moon's surface. Larger meteorites should have hit Titan on a regular basis. Mimas, Tethys and other satellites of Saturn have many large impact craters, and it doesn't seem likely that Titan should have escaped the fate of its neighbors. But because only two large impact craters on Titan have been discovered so far, this suggests Titan's surface is extremely young and changeable, with the missing craters having been buried or otherwise obliterated by weather or geologic processes. However, Nelson thinks the two craters could point to a more ancient surface. Both impact craters are quite large—one is 80 kilometers across, the second is 440 kilometers across—and Nelson says that such large craters tend to be extremely old.

Billions of years ago, when the solar system was still forming, everything was essentially an asteroid swirling around the sun. These "planetesimals" grew larger by slamming into each other, and eventually formed planetary cores. As time went on, there were fewer big asteroids remaining in this celestial collision course to make large impact craters. Nelson says that because large, presumably old craters have been preserved on Titan's surface, then the surface can't have changed very much over time.

Of course, the equation "big crater = old crater" does not always hold true. The dinosaurs on Earth were privy to that fact when a meteorite carved out a huge 180-kilometer wide crater a mere 65 million years ago. There are currently over a thousand near-Earth asteroids bigger than a kilometer in size, and some of them could potentially carve out large craters on our planet on some future day.

Charles Wood of the Planetary Science Institute notes that the craters on Titan look remarkably fresh, with finely defined edges. Older craters tend to look fuzzy as gravity or atmospheric processes wear them down. Either the craters are fairly recent, says Wood, or the surface of Titan changes so slowly that even ancient craters look newly-made.

The two impact craters are deep, with substantial topographic relief. Nelson, a member of the Cassini Visual and Infrared Mapping Spectrometer (VIMS) team, says they have spotted circular features that could be the flattened remains of other craters. "The surface is colored in a way that it appears to look like a crater, much as if Leonardo da Vinci had painted a crater on a white billiard ball, we'd think it was a crater when we saw it from a distance," says Nelson. "But it has very little topographic relief. Large, round features that don't have a lot of topographic relief have been seen before throughout the solar system; they're seen on the Moon, Mercury, and the Galilean satellites. Very large impacts create craters, and then the surface relaxes and fills in over time, but it leaves behind an albedo marking—a dark spot."

Nelson says that on Earth, craters tend to be completely obliterated over time, leaving no dark spots behind. So the fact that Titan has dark spots similar to those on more ancient, unaltered surfaces indicates to him that Titan's surface isn't seeing much alteration, either.

Wood wonders if any conclusions can be made about dark spots on Titan, whose origins are unknown. Further studies by Cassini's various instruments may provide more insight into these blemishes on Titan's skin. For Wood, the paucity of impact craters on Titan suggests a young surface. If Titan's surface was unaltered and ancient, it should be littered with hundreds or even thousands of craters. However, both Wood and Nelson say future Cassini images may turn up more craters.

Nelson adds that impact craters are not the only features on Titan that could betray the age of the surface. There is a large, bright region known as "Xanadu" that dominates one side of the moon, and there are no comparable large landscapes on the opposite side. Nelson says that if the surface were being continually altered, such bright areas would be more evenly distributed across Titan's entire surface.

"If you look at the eastern and western hemispheres of the Earth in the wintertime, you'll see snow. The snow has about the same brightness in any hemisphere," says Nelson. "On Titan, we're seeing more bright stuff in one hemisphere than the other, and that's suggesting that the bright stuff may be more permanent, and not getting subjected to weathering patterns."

The bright features on Titan are generally believed to be hydrocarbon ice. Ice on Titan is as hard as rock, although it's not made of silicate like the rocks on Earth. Titan's ice rocks are probably made of water or ammonia, or perhaps methane, ethane, propane, butane, or some chemical combinations. Even if the bright areas on Titan aren't fluffy snow, but instead represent a hard

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surface that is has been exposed, Nelson says this sort of exposure should occur uniformly on a surface that is continually being buffeted by wind and weather.

Cassini's close view of Titan from flyby. Image credit: NASA/JPL.

Wood, on the other hand, says we can't make any conclusions yet about the distribution of Titan's surface features. Distribution depends on many things, including how the features are made in the first place. "Earth is an ocean planet as seen from space above Hawaii," says Wood. "But the other hemisphere has much more land. We have no knowledge of what Xanadu is—high or low [elevation], old or young—we just know it is bright in images."

Nelson calls Titan's surface "old," because he is comparing it to the much-altered surface of the Earth. Wood calls Titan's surface "young," because he is comparing it to heavily cratered bodies like Jupiter's moons Ganymede and Callisto. But despite their different perspectives and different interpretations of the data, they come to a similar conclusion: Titan's surface age may be several hundred million years old, rather than several billions of years old, and comparable to regions of Mars. The martian surface has many impact craters, but also gradually evolves due to wind storms. Like Mars, Titan's surface may be changing slowly. Or, like Mars, Earth, and many other bodies in the solar system, Titan's surface is a mix of young terrain interspersed by older terrain that sees little change over the eons. Winds, liquid run-off, and volcanic eruptions may be altering the surface in ways we don't yet understand.

Scientists are hesitant to make any final conclusions about Titan at this time. Two impact craters allow for some comparative analysis, but not much. Hopefully, such disputes will be settled as more of the moon is imaged by the Cassini spacecraft. Titan is still mostly unexplored: only six flybys have been completed so far, with nearly 40 flybys scheduled over the next few years.

"This is much like watching the election returns on election night," says Nelson. "The first results coming from New Hampshire tell us something, but they're not the total pattern for the country. While the early returns have the incumbent paradigm shaking, the final tally isn't in yet."

Read the original article at http://www.astrobio.net/news/article1573.html.

NEW UNDERWATER VOLCANO FOUND NEAR SAMOAWoods Hole Oceanographic Institute release25 May 2005

An international  team of scientists, led by researchers at the Woods Hole Oceanographic Institution, Scripps Institution of Oceanography, University of Oregon and University of Sydney, has discovered an active underwater volcano near the Samoan Island chain about 2,400 miles southwest of Hawaii. During a research cruise to study the Samoan hot spot, scientists uncovered a submarine volcano growing in the summit crater of another larger underwater volcano, Vailulu'u. Researchers explored the unique biological community surrounding the eruption site, and were amazed to find an "Eel City," a community of hundreds of eels.

Vailulu'u rises 14,300 feet from the Pacific Ocean seafloor near the Samoan Islands. It ranges 21 miles at its base and is crowned with a mile-wide caldera that is 2,000 feet below the ocean surface. Image credit: Stan Hart, Woods Hole Oceanographic Institution.

This new volcano, dubbed Nafanua after the ferocious Samoan goddess of war, did not exist just fours years ago, according to co-chief scientists Stan Hart, a geochemist at Woods Hole Oceanographic Institution (WHOI), and Hubert Staudigel, a geologist at Scripps Institution of Oceanography. With a growth rate averaging eight inches per day, the volcanic cone has rapidly formed since the scientists' last expedition to this area in May 2001. Nafanua now stands at 300 meters, or nearly 1,000 feet.

"To actually have a documented case of an underwater volcano that has been constructed within a known period of time is very rare—this is one of those cases," said Hart, a Senior Scientist in the WHOI Geology and Geophysics Department.

Scientists were tipped off to the volcano's existence when they profiled the seafloor of the Vailulu'u crater using multi-beam mapping. Existing maps of the seafloor in the area gave little indication that this volcano existed. When sound beams were directed into the crater this time, they measured an unusually shallow depth. These interesting results prompted further investigation of the area using the manned submersible Pisces V—a seven-foot sphere that can dive to more than 6,000 feet, operated by NOAA's Hawaii Undersea Research Laboratory.  The water surrounding the volcanic cone is extremely turbid due to hydrothermal activity and the vigorous vents that produce this volcanic "fog" are obscured, according to Staudigel. Although visibility from the submersible was less than 10 feet, the researchers were able to observe the unique biological community surrounding the newly formed volcanic cone.  Much of Nafanua is covered with yellow "fluff," microbial aggregations that are produced by microscopic life feeding on chemical energy from the volcano's hydrothermal system. As this international team explored the area, they discovered a number of large communities of eels inhabiting the fragile cavernous rock pillars surrounding the hydrothermal vent area. As the submarine landed near this area, scores of eels, each approximately one foot long, emerged from the rock caves and crevices. The scientists named this novel marine hydrothermal community "Eel City."

"At this point we do not know why we found such extensive eel communities surrounding this volcano—it's a mystery that we hope to learn more about on future cruises," Staudigel said.

Within decades, continued growth of Nafanua could bring the summit of this volcano from its current depth of 600 meters to a depth of approximately 200 meters—close enough to the sea surface that it could provide a potential

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hazard to ocean navigation and coastal communities. Such hazards may include the explosive reaction between red-hot lava and seawater, or tsunamis that may be caused by the collapse of the newly built volcano.

"It is a good idea for us to keep our eyes on this area, but there is no real reason for concern about immediate danger," said Hart.

Three students from High Tech High in San Diego were aboard one of the two expeditions to Nafanua and assisted researchers in collecting and analyzing data. These students also created and maintained an in-depth Web site related to the cruise where they posted reports, maps, photos and videos from submersible dives. Also, the students and scientists aboard the ship participated in the first ever student-to-student videoconference between a high school and a research vessel with the help of HiSeasNet, a satellite communications system that provides continuous Internet connectivity for oceanographic research vessels at sea.

This research was funded by the National Oceanic and Atmospheric Administration (NOAA), the National Science Foundation (NSF) and the Australian Research Council. The discovery of Nafanua included investigators from oceanographic institutions in the U.S. and Australia, in addition to graduate, undergraduate and high school students. Investigators included Hart from Woods Hole; Staudigel, Anthony Koppers, Alexis Templeton, and Brad Tebo from Scripps; Craig Young and Sandra Brooke of the Oregon Institute of Marine Biology at the University of Oregon; Adele Pile of the University of Sydney; Ian Hudson from the British National Oceanography Centre, Southampton; Ray Lee from Washington State University; and Ed Baker of NOAA Pacific Marine Environmental Laboratory. This research was performed aboard two research vessels from the University of Hawaii, Ka'imikai O Kanaloa and Kilo Moana, and the NOAA submersible Pisces V.

Contact:Shelley DawickiPhone: 508-289-2270 or -3340E-mail: sdawicki@whoi.edu or media@whoi.edu

Read the original news release at http://www.whoi.edu/mr/pr.do?id=4818.

An additional article on this subject is available at http://www.astrobio.net/news/article1577.html.

EXTRATERRESTRIAL: IMAGINING OTHER WORLDSBy Edna DeVoreFrom Space.com26 May 2005

ET is coming to your living room in "Extraterrestrial," and no one is being abducted. Over the past several months, a top-notch group of American and British scientists teamed up with Blue Wave Productions, Ltd. (for the National Geographic) to imagine what ET is like on other worlds. It's all based upon our scientific understanding of life, stars and planetary systems. When filmed, Dr. Michael Meyer was NASA's astrobiology program scientist, and now serves as NASA Headquarters Mars Program Scientist; Dr. Seth Shostak is a senior astronomer here at the SETI Institute; Dr. Chris McKay is a leading Mars researcher at NASA Ames Research Center, Dr. Laurance Doyle conducts research on animal communication, and planetary systems around binary stars at SETI Institute and is the lead scientist at PlanetQuest, Inc., a new non-profit that will engage the public in finding extrasolar planets. Dr. Simon Conway Morris is a world-leader in evolutionary biology at Cambridge University in England... and the list goes on. These are serious and accomplished scientists—legitimate guys applying everything they know about stars, planetary systems, planetary evolution, and most especially, the evolution of life, to speculate on what life might be like on other worlds. In a word, the outcome is WILD!

Read the full article at http://www.space.com/searchforlife/seti_devore_ettv_050526.html.

APPROACHING MARSBy Tony PhillipsFrom NASA Science News27 May 2005

By the time you finish reading this sentence, you'll be 25 miles closer to the planet Mars. Earth is racing toward Mars at a speed of 23,500 mph, which means the red planet is getting bigger and brighter by the minute. In October, when the two planets are closest together, Mars will outshine everything in the night sky except Venus and the Moon. (You're another 50 miles closer: keep reading!)

It's only May, now, but Mars is already eye-catching. You can see it early in the morning, rising before the sun in the eastern sky, shining almost twice as bright as a 1st-magnitude star. A sky map, below, shows where to find Mars on Tuesday morning, May 31st, when it appears beautifully close to the Moon.

The Moon and Mars on June 29, 2005.

Why are we rushing toward Mars? It's simple orbital mechanics. Think of Earth and Mars as two runners on a circular race track, with lanes corresponding to planetary orbits. Earth, running fast on the inside lane, circles the course in 12 months. Mars, plodding along an outside lane, takes twice as long to go around. Every two years, approximately, Earth catches Mars from behind and laps it. That's where we are now, approaching Mars from behind. Relative speed: 23,500 mph.

We won't actually lap Mars until autumn, October 31st at 0319 Universal Time, to be exact. Only 43 million miles (69 million km) will separate us from Mars, then, compared to an average distance of about 140 million miles (225 million kilometers). It's a great time to send spacecraft there.

Mindful of that, NASA plans to launch the Mars Reconnaissance Orbiter (MRO) on August 10th, 2005. Because it takes 6+ months to reach Mars, the best time to start the trip is a month or so before closest approach—thus, August. MRO will arrive in March 2006, enter orbit, and begin a 2-year mission to map the red planet in greater detail than ever before.

The spacecraft's high-resolution cameras will be able to discern objects, such as rocks and rovers and crashed Mars landers, less than 1 meter across. A radar sounder will probe for underground water while spectrometers map the distribution of surface minerals. Other instruments will monitor the atmosphere, teaching researchers back on Earth how to forecast martian weather. These are key elements in NASA's plan to eventually send humans

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to Mars. (For details, see the Vision for Space Exploration, http://www.nasa.gov/missions/solarsystem/explore_main.html.)

The orbits of Earth and Mars.

The Mars rovers Spirit and Opportunity are already there. They arrived in January 2004 on the heels of another Earth-Mars close encounter in 2003. (Remember, this happens every two years.) The two robots were supposed to stop working months after they landed, worn down by wind, stuck in sand, or exhausted by too little solar power. Credit NASA engineering: Spirit and Opportunity are still rolling and, if they hold true to form, they'll be "alive" to see Mars Reconnaissance Orbiter when it gets there, a tiny point of light in the martian night sky, mapping the red planet for explorers of the future.

The HiRISE camera onboard the Mars Reconnaissance Orbiter has 5-times better resolution than cameras on other Mars orbiters and might be able to take pictures of the lost Mars Polar Lander.

Back on Earth people are going to enjoy watching Mars swell and brighten in the months ahead. By mid-summer, amateur astronomers with backyard telescopes will be able to spot polar ice caps and dust storms and strange dark markings. By autumn, even the least attentive of your neighbors will be remarking on "that bright red thing in the sky."

Mark October 31st as the best day of all: Mars will rise at sunset, hang overhead at midnight, and "blaze forth against the dark background of space with a splendor that outshines Sirius and rivals the giant Jupiter himself." That's how astronomer Percival Lowell described a similar close encounter in the 19th century.

Can't wait? Don't. You can see Mars any clear morning this summer. We recommend Tuesday morning, May 31st. Mars and the fat crescent Moon are going to have a pleasing close encounter in the dawn sky. Look for them rising in the east around 4:30 AM; the sight will absolutely wake you up. More good news: you're now 1000 miles closer to the planet Mars.

Read the original article at http://science.nasa.gov/headlines/y2005/27may_approachingmars.htm.

MARS: WINDOWS ON THE WORLDBy Joy CrispFrom Astrobiology Magazine30 May 2005

In their explorations of Mars, both the Spirit and Opportunity rovers found evidence that liquid water was once on the planet's surface. Joy Crisp, project scientist for NASA's Mars Exploration Rovers, discussed the rovers'

long journey and their surprising discoveries at a public lecture on May 19, 2005. This edited transcript of the lecture is Part 1 of a 4-part series.

Left: Rover impact simulation video frame. Each rover could bounce twenty or more times before coming to rest, with the average impact of a golf cart being dropped from the roof of a five-story building. Image credit: D. Maas/NASA/JPL/Cornell. Right: Mars has huge quantities of iron, as evidenced by the rusty red color of its soil. Image credit: NASA.

In January 2004, Spirit and Opportunity landed on Mars. In May of 2004, four months into the expected three month mission, Nagin Cox gave a talk in this lecture series on the status of the rover mission. And now, we are a year beyond that. I'm thrilled that I can come here and tell you that these rovers are still working on Mars, and that we've had a whole year's more worth of exciting discoveries. I'm also amazed to see how many people are in the audience here tonight, and not at the new Star Wars movie.

Dunes with Frost MGS MOC Release MOC2-743, 31 May 2004. Image Credit: Mars Global Surveyor, Malin Space System.

Mars today is a harsh place for life. It's cold, there's very little atmosphere, and what atmosphere is there is mostly carbon dioxide (CO2). Liquid water is not stable on the surface today. The water that's there is either in the form of ice or vapor.

Life as we know it requires liquid water. As you've probably heard, we are interested in whether life ever got started on Mars. We had some evidence from orbit that there was liquid water on the planet in the past. We've seen valley networks that were either carved by rivers similar to what we have on the Earth, or by near-surface groundwater sapping. We've also seen very intricate, fan-shaped delta deposits on Mars that are very similar to Earth's delta deposits.

So we sent the two rovers to two different places on Mars, on opposite sides of the planet. We picked two landing sites that had good evidence, from orbit, that there should have once been liquid water there on the surface. To be sure, we needed to go to the surface to see if there had been liquid water in the past,

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and to see if we could find clues in the rocks that would tell us whether it would have been a favorable environment for life.

We sent Spirit rover to Gusev Crater, where the evidence for past liquid water is in the landforms. From orbit, we saw this long sinuous dry river bed leading up to a crater. We thought water must have flowed through this valley and ponded in that crater, leaving lakebed sediments in that crater and possibly also river sediments. We wanted to send a rover there because the floor in the crater was nice and safe for landing, and we thought we might have a chance of finding water lain sediments.

We sent the other rover, Opportunity, to the plains of Meridiani, which is a nice smooth region, also very safe for landings. We had spotted the mineral hematite from orbit, using the Mars Global Surveyor's Thermal Emission Spectrometer. Hematite is iron oxide, Fe2O3. On Earth, hematite often forms in the presence of liquid water—not always, but often.

The mapped region on Mars showing hematite was a very large region, almost the size of Oklahoma. In high resolution images, along the edges of the flat smooth area, we saw layers in the rocks. We wanted to check to see if the hematite had been deposited by liquid water as a stack of rock layers. We have similar analogues to this sort of thing on the Earth.

Doing field geology is a lot like doing detective work. We are hunting for clues, trying to put the story together to build a case. In this example, we are trying to determine how these rocks formed. Was liquid water around when they formed, or later on when they sat around near the surface of Mars?

Opportunity bounced off this rock called "Bounce", the only rock in sight, and landed abruptly in Eagle Crater. The rock abrasion tool has left it drill marks on the rock. Credit:NASA/JPL/Cornell MSSS.

There's a TV detective show called "Monk," and the boss in the show once said, "How does he do it? I have two eyes, I see everything he sees. But I don't see everything he sees." The same kind of thing happens when a scientist looks at a rock. Scientists can look at a rock and say, "Wow! Isn't that amazing?" Then you look at it and say, "Well, there's some scratch marks and bumps on it. I don't know what that means." You don't see the same thing as a trained geologist, who has studied geologic processes and learned to read the clues. And so what I'm going to do in this talk is give you some feel for the kind of clues that we look for, and then what we have found with the Spirit and Opportunity rovers.

The main objective of our mission was try to find evidence of past liquid water and try to figure out what was it like when the water was around. One kind of clue to past liquid water is textures in rocks. We can look for that with camera images taken with the rover. We knew before we got there that we wanted to look for things like ripple marks, rounded grains that looked like they were cemented together, crossbeds, and rock layers that were at angles to each other. We see those kinds of things on the Earth when rocks are laid down by water.

The other kind of clues that we wanted to look for are specific types of minerals that can only form in the presence of liquid water. Either we know they have precipitated out of liquid water, or they're hydrated and actually contain bound water (OH or H2O). A few examples from the Earth include

calcite, dolomite, clays, salts, iron oxides that are hydrated, and sulfates that are hydrated. So we outfitted our rover to try to look for these things.

Another clue is to measure the abundance of the different elements. So we wanted to keep an eye out for differences in chemistry that we might expect if water was around, to look for higher abundances of elements that are easily dissolved in water and can then be re-precipitated in rocks.

Left: The Pancam design has a camera bar that contains Pancam and Navcam (navigation camera) heads. A "visor" changes the elevation of the cameras so the rover can look up or down. Image credit: Cornell University. Right: The Mini-Thermal Emission Spectrometer (Mini-TES). Image credit: NASA/JPL.

The first thing that a field geologist does when they go out in the field is survey the scene, looking around at the landforms and the shapes of the rocks. The rovers can also survey the scene, because cameras are at the top of a mast that is about five feet off the ground. The two science cameras have the clarity of 20/20 vision. So the pictures we get back are very much like what it would be like if you were there, standing on Mars. The mast can rotate, so we can get a complete 360 degree panorama, we can point it upwards and downwards, command it to look where we want it to look, and then take pictures from blue to green to red to the slightly near infrared—we can choose which filters to put in front of the eyes— and with red, green, and blue we can put them together and form the color images that we put out on the web.

Also at the top of the mast we have a thermal infrared emission spectrometer. You can think of infrared spectra as little squiggle fingerprints that help us figure out what minerals are present. We compare the infrared spectra from Mars with lots minerals we have measured on the Earth. So we can look at the rocks and soil around us, just as a field geologist would look around and say, "I think I see different kinds of rocks." We did that kind of survey with the rovers, to see where the different types of materials were, and to see what looked like the best places to go for clues to past liquid water.

A field geologist would walk over to something of interest. Because the rovers have wheels, we can send them to specific places, where they can investigate by using instruments on the end of their robotic arm. If you know any field geologists, they always carry a rock hammer out into the field. The reason you want to break open rocks is so that you can see the textures inside. The outside of rocks, especially on Mars, can be dust covered, and they also can have alteration coatings on the outside as they interact with the atmosphere and soil. So we put a grinding tool on the end of the robotic arm that clears away a spot, grinds into the rock, and gives us a window into the rock—just like a rock hammer would do.

The other thing a geologist always carries with them is a hand lens to look at shapes of grains, to help them identify what kind of minerals are there and to look at the texture of the rocks. So another thing that we put on that robotic arm is a microscopic imager, which gives us a close-up view of the rocks.

We have two other instruments on the rovers that are extras that geologists don't normally carry into the field—we usually have to come back to a laboratory with rock samples to take these kinds of measurements. We put on a chemical analyzer that gets us the abundances of the different elements in the periodic table. We also put on a Mössbauer spectrometer that tells us which iron-bearing minerals are in the rocks and soils, and how oxidized, or how rusty the rocks are. Mars is rich in iron, so it's a useful instrument to have.

With that assortment of instruments, including hazard cameras and navigation cameras for driving, we are equipped to go out and do some really exciting science.

Read the original article at http://www.astrobio.net/news/article1579.html.

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BOMBING THE COMETFrom Astrobiology Magazine, based on an ESO report31 May 2005

On July 4, 2005, the NASA Deep Impact spacecraft will visit Comet 9P/Tempel 1. It will launch a 360 kilogram (kg) impactor that should produce a crater on the surface of the comet and a plume of gas and dust. This experiment will be the first opportunity to study the crust and the interior of a comet. As the material inside the comet's nucleus is pristine, it will reveal new information on the early phases of the Solar System. It will also provide scientists with new insight on crater physics, and thereby give a better understanding on the crater record on comets and other bodies in the Solar System.

Left: Ground based image of comet 9P/Tempel 1 set for July 4th encounter and impactor. Image credit: NASA/JPL. Center: Comet Halley imaged by European flyby. Image credit: ESA. Right: The rocks inside a crater on the Asteroid Eros, as imaged before impact with the NEAR spacecraft. Numerous small impacts on the asteroid show brown boulders visible interior to the less exposed (white) lip of the crater. False-color for emphasis. Image credit: NASA/Eros.

The scientific outcome of the experiment depends crucially on pre-impact and follow-up observations. Before the impact, it is indeed necessary to accumulate a significant amount of data so as to fully characterize the comet, in terms of size, albedo (reflectivity), rotation period, etc. It is also essential to have a good baseline of observations before the impact to unambiguously discriminate the effects of the impact from the natural activity of the comet. Due to the currently limited understanding of the structure of these dirty snowballs - which is a rather precise definition of a comet—it is indeed far from clear what the effect of the impact will be. Although the most likely model predicts the ejection of a plume and a football stadium sized crater, other model predictions vary between the comet simply swallowing the impactor (with barely any visible effect) to the eventual break-up of the nucleus.

As part of a very large international collaboration, two teams of astronomers have used ESO's telescopes over several months to do pre-impact monitoring, taking images and spectra of the comet both in the visible and mid-infrared wavebands. These teams make observations typically once per month, using either the 3.6 m or the 3.5 m NTT telescopes at La Silla. New images show the latest of these monitoring pictures. Obtained during the night of May 4 to 5 with the EMMI instrument on the New Technology Telescope (NTT), it shows the comet, 100 million kilometers away from Earth. The coma extends more than 30 thousand kilometers from the comet nucleus, which is a 5 km diameter snowball hidden in the central bright core of the coma.

ESO will also actively participate in the post-impact observations. As soon as Comet 9P/Tempel 1 is visible after the impact from Chile, and for a whole week thereafter, all major ESO telescopes—i.e. the four Unit Telescopes of the Very Large Telescope Array at Paranal, as well as the 3.6 m, 3.5 m NTT and the 2.2 m ESO/MPG telescopes at La Silla—will be observing Comet 9P/Tempel 1, in a coordinated fashion and in very close collaboration with the space mission' scientific team. Among all observatories, the ESO La Silla Paranal Observatory will thus provide the best coverage of this one of its kind event.

The series of observations will provide unique clues to several questions related to comets. One will study in detail the chemical composition of the gas in the comet's coma, looking for fresh material from the nucleus' interior ejected during the impact. The careful study of this pristine material will provide important clues to trace the origins of comets, and so, on the formation of the solar system.

The other series of observations will focus on the dust and boulders that should be released during the impact, thereby characterizing the structure and

composition of the nucleus. Astronomers should then finally know what these "dirty snowballs" are really made of. First images by ESO telescopes will be obtained shortly after midnight, European time, on the night of July 4 to 5.

Read the original article at http://www.astrobio.net/news/article1580.html.

MOST AMERICANS BELIEVE ALIEN LIFE IS POSSIBLE, STUDY SHOWS By Tariq MalikFrom Space.com31 May 2005

While most depictions of extraterrestrials are confined to science fiction, nearly two-thirds of Americans believe that some form of alien life exists somewhere in the universe, according to a new survey. The telephone poll, which questioned 1,000 Americans, found that 60 percent of those surveyed believe extraterrestrial life exists on other planets.

Read the full article at http://www.space.com/news/050531_alienlife_survey.html.

SPIRIT, THE PROBLEM CHILDBy Joy CrispFrom Astrobiology Magazine1 June 2005

In their explorations of Mars, both the Spirit and Opportunity rovers found evidence that liquid water was once on the planet's surface. Joy Crisp, project scientist for NASA's Mars Exploration Rovers, discussed the rovers' long journey and their surprising discoveries at a public lecture on May 19, 2005. This edited transcript of the lecture is Part 2 of a 4-part series.

Spirit is the problem child, so to speak. It took us a lot longer to reach our science objectives with Spirit, but it's really coming into its own right now. In the first three months, all that Spirit encountered was volcanic basalt lava. Here we were, trying to find lakebed sediments or river sediments, some clues to past liquid water. We found evidence for little trickles of water, clues that tiny amounts of water had gotten into these volcanic rocks, but we weren't finding any evidence of a past environment that would have been favorable for life. At this point at Bonneville Crater, we saw that the rover was still in good health, so we made the bold attempt to try to drive to the Columbia Hills.

We weren't sure we would make it. We decided to drive as fast as we could, and five months after landing, on martian day 156, we made it to the base of the Hills. We immediately found a very different kind of rock that had signs of past liquid water.

Left: False color view of shading differences between soils near the Spirit's location. Right: Columbia Hills loom with increasing detail at the Spirit rovers' Gusev Crater site. Image credit: NASA/JPL.

There's a diversity of rocks in the Hills. They range from grey to orange, which is telling you how oxidized or altered they are, how rusty they are. You see some rocks that look massive and smooth, and some that look corroded. This might be due to variations in water alteration. The "smoking gun" evidence for liquid water was found in the rock Clovis. This rock was soft compared to the basalt lava rocks out on the plains. If you've ever been to Hawaii, the basalt lava there is very hard. It has been difficult to grind into this sort of rock on Mars.

The results from the Mössbauer spectrometer told us that the mineral goethite was abundant in this rock. Goethite's formula is FeO(OH)—it contains OH, which only forms in the presence of liquid water. That water may have been groundwater alteration; it may not have been flowing on the surface. We aren't sure.

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We have argued about all the rocks in the Hills, as to whether they are sandstones laid down by liquid water, or volcanic eruption ash tuffs or airfalls, or whether they were formed by impacts. We found pyroxene, olivine, and magnetite, which are volcanic minerals, but we also found hematite, goethite, and nanophase oxides, so it's like a volcanic rock that has been altered, or volcanic rock that maybe got transported by water, or impacted.

There is some layering in these rocks in the Hills. We've been trying to test the hypothesis as to whether these layers were put down by water, one layer at a time, or if they represent volcanic eruption blasts, one blast at a time, or one impact event at a time. We haven't been able to figure that out yet.

The path of Spirit along the floor Gusev Crater to Columbia Hills as seen by the navigation camera. Image credit: NASA/JPL.

One of the unusual things that we've found in some of the rocks in the Hills is that, in the infrared, we get a signature that is similar to fresh volcanic glass. This has been puzzling to us because we're finding that in conjunction with this is highly altered, oxidized minerals like the goethite and the hematite. The chemistry is showing high bromine sometimes and high chlorine and high sulfur, which aren't in normal volcanic amounts.

So how could we have fresh volcanic glass in the rock? One possibility is that instead of fresh volcanic glass, maybe there is impact glass in here—minerals that were impacted and shocked and converted into a glassy phase. Or, maybe they're so altered that there's some kind of cruddy, amorphous phase that was formed when the water affected these rocks - we don't know yet.

I hope you're getting a sense of how puzzling these rocks have been. If we're going to get an answer, we'll probably get it from the textures of the rocks. As to whether they are sandstones, sedimentary, laid down by water, whether they're volcanic airfall deposits that came out of an eruption column and landed where they are, or whether they formed by impact blast, when an incoming asteroid hit Mars and broke things up. Or it could be a combination of some of these processes. That could be why we're so stumped. It's hard to sort things out when there was more than one process going on.

But we're very happy because we are seeing signs of past liquid water. Even if this was groundwater and the rocks were just soaked by it, that does represent an environment where life could have possibly existed.

You can walk for very long distances on the Earth and keep encountering the same kind of rock. When you send a rover to Mars, you don't know if you're going to have the same thing happen. So a great thing about Spirit is, having finally made it to the Hills after that long drive, we are now encountering, over very short distances, striking changes in the chemistry and the minerals that we're finding in the rocks.

There are also some signs in the soil of the action of liquid water. One place where the rover wheel had disturbed the soil was very white. We started taking measurements, and there was a striking amount of salt. I'm not

referring to table salt—NaCl—but to sulfate salt. This was iron sulfate salt, and it was the first time we've seen iron correlating with sulfur. This is a hydrated iron sulfate, so this was our second "smoking gun" evidence indicating past liquid water. The soil is about 50 percent salt, so water must have been percolating in this soil, soaking it, and these salts precipitated out of it. Or that happened somewhere else and they were transported here and formed the soil.

When Spirit climbed to Larry's Lookout, and looked back at where we had come, we saw layered rocks that were connected with one another. We saw that these layers were dipping at about a 20 degree angle, at about the same dip as the slope of the hill we had come up. These exposed layers, to a geologist, are very exciting, because you can follow the layers at great length to see if they change, and you can tell what's younger and what's older.

We're about halfway up to the top of the Hill, but we found such good stuff right where we are that we're spending some time here, looking at these rocks before we continue our way up. We're exploring, so if we see something that looks good we might head off into a different direction. We may change our minds as we go.

Read the original article at http://www.astrobio.net/news/article1583.html.

COMET PUT ON LIST OF POTENTIAL EARTH IMPACTORSFrom New Scientist1 June 2005

The comet is the largest, and therefore most potentially devastating, of the 70 objects now being tracked. But while it appears to be bang on target to cross the Earth's orbit, the timing means the chances of an actual collision are very low. The listing of Comet Catalina underscores the uncertainty in the knowledge of whether comets or asteroids pose a greater threat to Earth. Previous estimates of the proportion of the impact risk posed by comets have varied widely, from 1% to 50%, with most recent estimates at the lower end. But comets are larger and faster-moving, on average, so their impacts could be a significant part of the overall risk to human life. And, unlike asteroids, they lie on randomly-oriented and usually highly elongated orbits. This makes them much more likely to remain undiscovered until they are very close to Earth.

Read the full article at http://www.newscientistspace.com/article/dn7449.html.

FUNDING FOR MOON, MARS PROJECTS PROMISEDBy Pam EastonFrom Associated Press and Space.com1 June 2005

NASA's new administrator and Texas Republican Representative, Tom DeLay, said Tuesday the space agency will have the necessary funding to implement President Bush's vision to send astronauts back to the moon and to Mars.

"We have the money to do good things," said Michael Griffin, who has visited at least seven of NASA's centers since he was appointed in April. During a two-day visit at the home of human spaceflight, he spoke with astronauts, flight directors and other top administrators.

SCRIPPS-LED GLOBAL OCEAN WARMING RESEARCH PAPER PUBLISHED IN SCIENCE EXPRESSScripps Institution of Oceanography release2 June 2005

Research led by scientists at Scripps Institution of Oceanography at the University of California, San Diego, that describes the first clear evidence of human-produced warming in the world's oceans will be published June 2, 2005, in the peer-reviewed journal, Science Express. The research was first announced publicly and widely publicized in February at a news briefing at the annual meeting of the American Association for the Advancement of Science in Washington, DC (seehttp://scrippsnews.ucsd.edu/article_detail.cfm?article_num=666). The paper's abstract notes: "A warming signal has penetrated into the world's oceans over the past 40 years. The signal is complex, with a vertical structure that varies widely by ocean; it cannot be explained by natural internal climate variability or solar and volcanic forcing, but is well simulated by two

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anthropogenically forced climate models. (The authors) conclude it is of human origin, a conclusion robust to observational sampling and model differences. Changes in advection combine with surface forcing to give the overall warming pattern. The implications of this study suggest society needs to seriously consider model predictions of future climate change."

Journal reference:Tim P. Barnett, David W. Pierce, Krishna M. AchutaRao, Peter J. Gleckler, Benjamin D. Santer, Jonathan M. Gregory, and Warren M. Washington, 2005. Penetration of human-induced warming into the world's oceans. Science Express, published online June 2 2005; 10.1126/science.1112418, http://www.sciencemag.org/cgi/content/abstract/1112418v1.

Contacts:Contacts: Mario Aguilera or Cindy ClarkPhone: 858-534-3624E-mail: scrippsnews@ucsd.eduhttp://scrippsnews.ucsd.edu

Read the original news release at http://scrippsnews.ucsd.edu/article_detail.cfm?article_num=684.

THE CENTER FOR THE STUDY OF LIFE IN THE UNIVERSEBy Frank DrakeFrom Space.com2 June 2005

We live in an awesome universe, rich in remarkable, complex, phenomena. Every advance in our observing capabilities reveals new and often unpredicted objects, such as other planetary systems, and processes in the universe. Of all these phenomena, the most marvelous, and at the same time of the greatest interest to us as human beings, is life in the universe. How many planets exist which might support life? Indeed, what is required for life to exist? How does life start? How does it evolve, and what fabulous creatures can evolution produce? How often do intelligent creatures appear in the giant tapestry of life? It is exactly these questions, and all of them, which are being addressed by the scientists of the Center for the Study of Life in the Universe, LITU.

Read the full article at http://www.space.com/searchforlife/seti_drake_LITU_050602.html.

NASA SCIENTISTS CONFIRM LIQUID WATER ON EARLY EARTHNASA/ARC release 05-353 June 2005

Research funded partly by NASA has confirmed the existence of liquid water on the Earth's surface more than 4 billion years ago. Scientists have found that the Earth had formed patterns of crust formation, erosion and sediment recycling as early as 4.35 billion years ago. Their findings came during a study of zircon crystals formed during the earliest period of Earth's history, the Hadean Eon (4.5 billion to 4.0 billion years ago).

"NASA is interested in how early the Earth had abundant liquid water. If oceans form early in a planet's history, then so can life," said Carl Pilcher, senior scientist for astrobiology at NASA Headquarters, Washington. "Learning how early oceans formed on Earth will help us understand where else oceans and perhaps even life may have formed in this solar system and in planetary systems around other stars."

"This work provides direct evidence that the Earth was probably habitable within a hundred million years of its formation," said Bruce Runnegar, director of the NASA Astrobiology Institute (NAI) at NASA Ames Research Center, Moffett Field, CA, which provided some of the study's funding.

Published in the May 6, 2005, edition of Science, the research was conducted by T. Mark Harrison of the Research School of Earth Sciences, Australian National University, Canberra and the University of California, Los Angeles; and E. Bruce Watson of the Department of Earth & Environmental Sciences at Rensselaer Polytechnic Institute, Troy, NY. Field research was completed in Western Australia's Jack Hills, which preserve a record of the Hadean Eon.

Watson and Harrison devised a new method of determining the temperatures at which the rocks formed. The team extracted and examined more than 50,000 zircons, crystals about the width of a human hair, which have been exposed through natural erosion in the Jack Hills. From the 50,000 zircons,

only a couple of hundred were older than 4.2 billion years. Measuring the temperature at which the rocks melt gives an indication of the conditions in which they formed.

"Rocks formed as a result of the thermal energy from meteorite impacts would be bone dry and melt at greater than 900 degrees Celsius," said Harrison. "In contrast, our study has found that Hadean rocks melted at a consistent average temperature of 690 degrees Celsius. Water, which is a very powerful catalyst, must have been present in very large amounts for rocks to melt at such a relatively low temperature."

This discovery supports the proposal by Harrison's group four years earlier that a heavy oxygen isotope signature in the Hadean zircons is evidence for liquid water at or near the Earth's surface by 4.3 billion years ago.

The NAI, founded in 1997, is a partnership between NASA, 16 major U.S. teams and five international consortia. NAI's goal is to promote, conduct and lead integrated multidisciplinary astrobiology research and to train a new generation of astrobiology researchers. For more information about the NAI on the Internet, visit http://nai.arc.nasa.gov. For information about NASA and agency programs on the Internet, visit http://www.nasa.gov.

Journal reference:E. B. Watson and T. M. Harrison, 2005. Zircon thermometer reveals minimum melting conditions on earliest Earth. Science, 308(5723):841-844, http://www.sciencemag.org/cgi/content/abstract/308/5723/841.

Contacts:Nicholas A. Veronico/Michael MewhinneyNASA Ames Research Center, Moffett Field, CAPhone: 650-604-1939, 650-604-9000E-mail: nveronico@mail.arc.nasa.gov

Additional articles on this subject are available at:http://spaceflightnow.com/news/n0506/03earthwater/http://www.terradaily.com/news/early-earth-05e.html

NASA NAPSBy Patrick L. Barry and Tony PhillipsFrom NASA Science News3 June 2005

Space travel is sleepless work. Despite NASA recommendations that astronauts sleep 8 hours a day, they usually don't. Strange sights and sounds, the stress of riding a powerful rocket, the lack of a normal day-night cycle—all these things tend to keep space travelers awake. Studies show that astronauts typically sleep 0.5 to 2.5 hours less than they do on Earth. Although many astronauts report feeling fully rested after only six hours of sleep, the fact is, sleeplessness can cause irritability, forgetfulness and fatigue—none of which astronauts need to deal with while piloting complicated 'ships that hurtle through space at tens of thousands of miles per hour.

Could you sleep like this? Payload specialist Bjarni V. Tryggvason, representing the Canadian Space Agency (CSA), sleeps on the Space Shuttle Discovery's mid-deck floor. Tryggvason elected to not use a pillow, allowing his head to float freely in the Microgravity environment.

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The solution seems simple: take a nap. But naps are a double-edged sword. Sometimes napping can leave you feeling even drowsier than before. If your body enters a deep sleep, trying to wake after only an hour or so can be very unpleasant, and you might remain groggy for some time afterward. This is called "sleep inertia."

Why do naps sometimes backfire? Researchers don't yet know the physical causes of sleep inertia, but they would like to be able to predict, at least, when it's going to strike. This could help doctors prescribe naps of the right time and duration for drowsy people in high-risk professions. Helping astronauts nap was the goal of a recent series of experiments funded by NASA in cooperation with the National Space Biomedical Research Institute. In those experiments, led by David Dinges, a professor at the University of Pennsylvania School of Medicine, 91 volunteers spent 10 days living on one of 18 different sleep schedules, all in a laboratory setting. The sleep schedules combined various amounts of "anchor sleep," ranging from about 4 to 8 hours in length, with daily naps of 0 to 2.5 hours.

To measure how effective the naps were, the scientists gave the volunteers a battery of tests probing memory, alertness, response time, and other cognitive skills throughout the experiment. They also measured things like core body temperature and hormone levels in blood and saliva, all of which fluctuate in a natural daily cycle known as a person's "biological clock." In general, they found, longer naps were better. No surprise there. But they also found that some cognitive functions benefited more from napping than others.

Shuttle pilots need to be mentally sharp to operate controls like these.

"To our amazement, working memory performance benefited from the naps, [but] vigilance and basic alertness did not benefit very much," says Dinges.

"Working memory," he explains, "involves focusing attention on one task while holding other tasks in memory ... and is a fundamental ability critical to performing complex work [like piloting a spaceship]. A poor working memory could result in errors."

For vigilance and alertness, which involve the ability to maintain sustained attention and to notice important details, they found that the total amount of sleep during 24 hours remained the most important factor. Another interesting finding was that naps didn't work as well for volunteers on a nocturnal schedule. Sleep schedules for some of Dinges' subjects were flipped, so that anchor sleep occurred when their bodies thought it was daytime. The nap, then, fell in the middle of biological nighttime. This simulated what might happen when an astronaut's biological clock is out of sync with the mission schedule. These out-of-sync volunteers had a very hard time waking from naps, and the grogginess of sleep inertia lasted for up to an hour. Some sleep inertia did occur after naps on a normal schedule too, notes Dinges, but the inertia after a nighttime nap was much more severe.

The ultimate goal, says Dinges, is to tie all these data together into a mathematical model of naps. Such a model, written as a computer program, could prescribe effective naps compatible with the scheduling demands of a mission. Not only astronauts would benefit from such a program, but also doctors, pilots, firefighters... the list goes on.

Such a program is still in the future. Meanwhile, Dinges notes another finding of their study: Naps are a short-term fix, offering only temporary boosts in

mental acuity. "They cannot replace adequate recovery sleep over many days," he says.

In the end, there's no substitute for 8 sweet hours of shut-eye.

Read the original article at http://science.nasa.gov/headlines/y2005/03jun_naps.htm.

DRIVING ON THE ROADMAPFrom Astrobiology Magazine5 June 2005

The NASA Astrobiology Roadmap provides guidance for research and technology development across the NASA enterprises that encompass the space, Earth, and biological sciences. The ongoing development of astrobiology roadmaps embodies the contributions of diverse scientists and technologists from government, universities, and private institutions. The Roadmap addresses three basic questions: How does life begin and evolve, does life exist elsewhere in the universe, and what is the future of life on Earth and beyond?

One of the most interesting lists in the Roadmap include example investigations. For those who are inclined to "doing," the list is fertile and rich with ideas for thinking deeper about how scientists answer some of the most difficult and enduring questions posed by astrobiology. This survey highlights those examples, with links to help understand the more complex endeavors.

Study the relationship between stellar metallicity and planet formation. Determine if there is a galactic habitable zone. Model the origin of planetary systems, especially water delivery to and loss from terrestrial-like planets of various size and mass. Determine how water loss affects climate, surface, and interior processes, and how these changes affect habitability. Develop comprehensive models of the environments of terrestrial-like planets to investigate the evolution of habitability.

Left: HD 28185 b is the first exoplanet discovered with a circular orbit within its star's habitable zone. Image Credit: STScI Digitized Sky Survey. Right: The statistical argument for life elsewhere may trump philosophical purity Image credit:NASA/STScI/ESA.

Investigate novel methods for detecting and characterizing extrasolar planets, particularly those that might lead to an improved understanding of the frequency of habitable Earthlike planets.

Use atmospheric models to understand the range of planetary conditions that can be determined from low-resolution, full-disk spectra at visible, near-infrared, and thermal wavelengths. Use data on Venus, Earth, and Mars to validate these models. Model a variety of biosignatures, including the ozone 9.7 mm band and oxygen A band signatures and their variations over Earth's geological and biological history.

Target well-instrumented robotic rovers to sites of past aqueous sedimentation to analyze rocks for geochemistry, aqueous minerals, organic matter, and fossil biosignatures. Develop flight-capable instrumentation for the unambiguous detection of biosignatures preserved in surface and subsurface rocks, soils, and ices.

Explore the atmosphere and surface environments of Titan for evidence of complex organic chemistry and water, to provide a context for understanding potential habitability and prebiotic chemistry. Simulate the environment of Titan to aid in designing in situ missions and to interpret data returned

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therefrom. Develop astrobiology instrumentation that can survive the low temperature, high radiation environments of the surface of Europa. Use in situ methods to test models that predict the presence of energy sources for supporting life.

Trace the cosmic formation of prebiotic materials from the formation of interstellar molecules and solids through the processing of these materials to produce more complex compounds. Conduct laboratory experiments and simulations to provide a framework for analyzing meteorites and samples returned from asteroids and comets, and for interpreting spectra of interstellar clouds. Analyze meteorites and returned samples to understand the nature of extraterrestrial organic compounds. Identify the organic compounds and complexes produced under primordial planetary conditions through laboratory simulation experiments.

Search for mechanisms of enantiomeric enhancement that introduced chirality into biological systems. Investigate polymers other than nucleic acids that have the potential to have been precursor molecules capable of containing genetic information. Investigate the RNA-catalyzed active site in ribosomes to better understand how RNA could have first evolved to mediate translation in early forms of life.

Search for pigments that were plausible components of the prebiotic environment and have the capacity to capture and transduce light energy into chemical energy. Investigate redox reactions in which hydrogen serves as a source of free energy that could plausibly be available for early forms of life. Investigate mechanisms by which early boundary membranes could couple the energy available in ion gradients to the synthesis of high-energy compounds such as pyrophosphate.

Determine how ionic and polar nutrients could permeate membrane boundaries to supply monomers and energy for intracellular metabolism and biosynthesis. Investigate polymerase reactions that can take place in membrane-bounded microenvironments, using external sources of monomers and chemical energy. Establish membrane-bounded protein synthesis systems that incorporate ribosomes and mRNA in lipid vesicles.

Examine the earliest sedimentary rocks for biosignatures, such as microfossils and chemical fossils. Search for biosignatures of key microorganisms and metabolic processes (e.g., photosynthesis) in rocks of Archean age. Analyze genomic sequence data of prokaryotes and identify correlations between lineage divergence and events in the history of the biosphere.

Study carbon isotopes and other proxies of environmental change in Neoproterozoic rocks to better understand the history of global climatic perturbations that may have influenced the early evolution of complex life. Search for fossil evidence of eukaryotes in rocks of Proterozoic age to determine the morphology, ecology, and diversity of early eukaryotes. Analyze genomic sequence data of unicellular eukaryotes to gain insights into the early evolution of eukaryotic complexity, including the acquisition of cellular organelles.

Examine the evolutionary, ecological, and taxonomic changes in Earth's biota following a known asteroid impact event. Investigate a known mass extinction event in the fossil record to determine whether it was caused or intensified by an extraterrestrial event, such as an impact or a nearby supernova.

Experimentally observe the assembly of genes into novel metabolic pathways as an adaptive response to environmental changes. Examine microbial genome rearrangements, including gene deletion and acquisition processes, in response to nutrient change and physical-chemical stress. Investigate the diversity of genome stability in physiologically and genomically different microbes.

Investigate small molecule interactions and their role in coordinating metabolic activities in mixed phototrophic/chemotrophic microbial communities. Examine adaptive mutations in individual microbial species of mixed communities in response to environmental perturbations. Examine the susceptibility of established microbial communities to invasion by foreign microbes.

Investigate the intrinsic properties and stability of critical biomolecules that allow microorganisms to survive severe freezing and thawing cycles. Biochemically characterize DNA-repair mechanisms that allow microorganisms to recover from radiation damage. Study survival strategies

that might allow microbes to maintain their viability for very long periods of time (thousands to millions of years).

Construct biogeochemical models of ecosystems and test the models with isotopic and functional genomic analyses of the constituent parts of the ecosystems. Document the ecological impact of changes in climate, habitat complexity, and nutrient availability upon the structure and function of a selected ecosystem, as a guide for understanding changes that might occur over time scales ranging from abrupt events (a few years or less) to millions of years.

Document the impact of the space environment upon microbial ecosystems that might be ejected into space by an impact event. Examine the survival, genomic alteration, and adaptation of microbial ecosystems in a simulated martian habitable environment. Interpret the significance of the findings regarding the potential for the forward biological contamination of Mars. Examine the effects of the space environment upon the biosynthesis and utilization of microbial biomolecules that play key roles in biogeochemical processes.

Determine additional organic biomarkers that will help to chart the presence and development of photosynthetic microbiota in Precambrian rocks. Determine the features of sedimentary laminated textures that uniquely require biological processes. Identify examples of chemical, mineralogical, and stable isotopic biosignatures that can indicate the presence of subsurface biota (e.g., microbes living in aquifers), and that can be preserved in ancient rocks.

Determine the nature and fate of reduced gases that are produced by specific microbial ecosystems in an anoxic ("pre-oxygenated") biosphere. Carry out laboratory, observational, and modeling studies to separate false from true biosignatures [e.g., atmospheric O2 in a range of planetary environments].

Read the original article at http://www.astrobio.net/news/article1591.html.

OPPORTUNITY'S ESCAPE FROM DUNEBy Joy CrispFrom Astrobiology Magazine6 June 2005

In their explorations of Mars, both the Spirit and Opportunity rovers found evidence that liquid water was once on the planet's surface. Joy Crisp, project scientist for NASA's Mars Exploration Rovers, discussed the rovers' long journey and their surprising discoveries at a public lecture on May 19, 2005. This edited transcript of the lecture is Part 3 of a 4-part series.

Opportunity rover landed in Eagle crater, and we immediately found an exposed rock outcrop. We spent a lot of time working up and down this outcrop, trying to read the record in the rocks. It was very unusual looking rock—finely layered, with these slightly bluish gray spheres the size of peppercorns that we nicknamed blueberries. They were all over this soil, and when we finally got a close-up look, we saw the blueberries were also embedded in the rock. Our chemical analyzer showed high amounts of sulfur, chlorine, and bromine. Also, the sulfur correlated strongly with magnesium, and somewhat with calcium. The clues told us that this rock was very rich in sulfate salt.

The Mössbauer spectrometer found its "smoking gun" evidence for liquid water right away. The first clear clue of liquid water found by Opportunity was the mineral jarosite. This mineral, packed with OH, can only form in the presence of liquid water. It's basically a hydrated sulfate. The other thing about jarosite that's very special is that it only forms in acidic water. So, it was telling us something about the conditions of the water when the water was there.

We studied the rocks in that outcrop very carefully, took lots of microscopic images, put them together in mosaics, and then we traced the faint lineations, the curved lines that we could see in this rock. The sedimentologists on the team compared these lineations against what we see on the Earth, in rocks that are deposited by wind, water, and volcanic blasts. It turned out that liquid water had to have made the shapes and geometries of these curving lines. So that tells us that these rocks were deposited in flowing liquid water on the surface of Mars.

After the rocks were deposited, they had additional water soaking. It wasn't enough that they formed in flowing liquid water, these rocks continued to be

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soaked in groundwater, and formed these little blueberries in the rocks that are rich in hematite. These concretions form when you soak rocks that are porous, and the iron precipitates out and forms these hard spheres.

Left: Empty nest view back to landing petal from the mobile Opportunity rover, which has ventured to the crater's rim. Image credit: NASA/JPL. Right: Overhead view of Endurance Crater. Image credit: MGS/NASA/JPL.

There are also holes which were probably made by minerals easily dissolved in water which first precipitated from water and then later may have also been removed by water. So, there were very good signs that this rock was soaked in water for quite a bit of time. Just so you know I'm not making this up, these are rocks in Utah that are similar, layered sandstone with iron-rich concretions that formed by the same kind of mechanism.

After we finished with Eagle crater, we popped our heads out and said, where next? Looking at the orbital images, we decided we wanted Opportunity to go to Endurance crater, a big, 150 yard diameter crater, one and a half times a football field length. In the orbital images, Endurance crater has a white rim. Our geologic hypothesis was that we might find the same kind of rocks that we saw in Eagle crater in the rim. We might also find older rocks as we looked down into that crater.

Left: A feature called "Burns Cliff", part of the rocky outcrop in Endurance Crater. Image credit: NASA/JPL. Right: Rover computer rendering on the edge of a depression, much like Opportunity's perch on the edge of Endurance Crater. Image credit: Maas/NASA/JPL.

We took measurements of the rock at the top of the rim with our robotic arm, and sure enough, it was the same kind of rock we saw in Eagle crater: finely layered, with jarosite, that mineral that can only form in water, high sulfur, high chlorine, high bromine. They are sedimentary rocks deposited in flowing liquid water, evaporite-containing sandstones. We went down into the crater, and it was a fairly steep slope: from 18 to 30 degrees. So it wasn't easy, and the hardest part was making sure we could get back out. There was much more of an exposed rock record here than in Eagle crater. We did a very careful job of checking out the layers as we went down and ground 11 holes along the way, and took close-up microscopic images of them. We did see differences in texture, although essentially the rock all the way down was the same kind of rock. It had the same kinds of minerals, with subtle differences in texture, and some not-so-subtle changes in chemistry.

Wind deposited a lot of the rocks in Endurance crater. The good news is, they're full of evaporite minerals, minerals that precipitated out of liquid water somewhere else, in water that was very salty, forming rock very rich in sulfate salts and jarosite. So there is a story here of a lot of liquid water on Mars, in an area the size of Oklahoma. That's a good thing if you're looking for environments that could have been favorable for life.

Now, both here and at Gusev crater for Spirit, there are some obstacles to being a really favorable place for life, if life ever got started here. And one of these is water chemistry. Both here and at Gusev, the signatures that we see are that the waters were acidic. Now, on the Earth, we do have microorganisms that have adapted to those kinds of environments and can thrive. So that doesn't rule it out, it just makes it a bit harder for life to exist,

and it may be a difficult environment to start life. The other thing is that both places are salty, with these sulfate salts. And that can be difficult also for life, but not impossible. We have very many examples on the Earth of microorganisms that can thrive in salty waters. There is also an issue with the persistence of water at Meridiani, where we see sand dune and sand sheet deposits. When those were being deposited, were times when water wasn't around. So the water may not have hung around continuously, and that also might have made it difficult for life.

After Opportunity visited Eagle crater, we headed south. The orbital view of this terrain shows some ripples, and as we headed south the ripples get bigger and bigger. Finally we encountered an extremely large dune 30 centimeters tall that happened to be right in a place where the terrain stepped up about 25 centimeters. We had been happily commanding the rover to drive a certain distance, and the wheels plowed into this deep dune, and the rover thought everything was fine. "Hey, my wheels are turning, I'm moving, I'm making progress." Then we got the pictures back, and said, "Oh my goodness, we're not where we thought we were. And look at the wheels, they're almost completely buried."

We didn't want to do something that would get us into worse shape, so we had to engage in a crash test program in the testbed with our Earth rover, and try to simulate the conditions with the kind of soil that we were seeing, with the soil caking up on the wheels and making the treads disappear. We've done about five movements on Mars, and have gone about five inches. So we are not stuck, we just have to get out slowly so we don't get into more trouble. We're making very good progress even though it's just an inch at a time. I'm sure we'll get out of it. When we do, we want to try to head south, going from Endurance crater down to the much bigger Victoria crater.

The terrain heading down toward Victoria crater looks brighter in the orbital images, and it looks somewhat rougher. It is possible that this brighter color is bigger dunes that have fine dust on them that give them a brighter color, and we've started encountering that. If it becomes too difficult to drive through we might choose another path to take us to Victoria crater. We don't know how long it will take us to get there, so stay tuned.

Read the original article at http://www.astrobio.net/news/article1592.html.

GRIFFIN SUPPORTS ISRUMars Society release23 May 2005

In a speech at NASA Kennedy space Center May 20, NASA Administrator Dr. Mike Griffin endorsed in situ resource utilization (ISRU) as a key technology for implementing human exploration of the Moon and Mars.

Regarding ISRU, Dr. Griffin said, "In going to the Moon, returning to the Moon to stay, going to Mars—we absolutely must plan on use of local resources at those sites and other sites, such as asteroids. We can't haul everything with us that we want to take except for the first few years. So it's a key, core, must have, can't do without technology, as far as I'm concerned."

Griffin is right. ISRU is the central technology to enable near-term, low cost, and sustainable human exploration and settlement of the Moon and Mars. Its use is key, for example, in implementing the Mars Direct plan. Griffin is the first NASA administrator to know this, and his open support for ISRU technology development, and therefore presumably efficient mission architectures based upon ISRU, is an enormously positive development.

An in-depth discussion of ISRU technologies for creating fuel, oxygen, plastics, glasses, metals, food, and other useful materials out of locally available substances on the Moon and Mars will take place at several dedicated sessions at the 8th International Mars Society Convention, Coors Stadium, University of Colorado Boulder, August 11-14, 2005. Registration is now open at www.marssociety org.

BOOK PREVIEW: SEEDING THE UNIVERSE WITH LIFE—SECURING OUR COSMOLOGICAL FUTURE By Michael Mautner31 May 2005

Within this century, we can start seeding other solar systems with life. We can launch the microbial representatives of our family of gene/protein life toward other young stars, using solar sails. Our astro-ecology experiments

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suggest that they will find fertile soils. Some of this new life can develop into intelligent beings who will promote life further in the galaxy.

Expanding life is motivated by a panbiotic ethics. These ethics can be based on the unique place of life in nature, and its drive for self-propagation. We are part of Life, which defines our purpose: to secure and propagate life, and to elevate it into a controlling force in nature. Our descendants will then promote life further, and may seek eternity. In them, our human existence will find a cosmic purpose.

The book starts with a brief introduction of a life-centered astro-ethics. These ethics are based on the scientific view of life: the complexity that makes it unique in nature; the special coincidence of physical laws that make biology possible; and the basic unity of all cellular gene/protein life-forms. From these observations, the author concludes that our basic identity as living beings implies a human purpose: to forever safeguard and propagate life in the universe.

The next chapters address astro-ecology, the resources for life in the Solar System and in the more distant future. These sections describe the author's research on meteorites, which showed that bacteria, algae and even vegetable cultures—asparagus and potato—can grow on nutrients in meteorites. Based on the measured nutrients, the book estimates the immense amounts of life that we can construct in our Solar Sytem and about billions of other stars. This immense future will follow once we established a foothold in space to serve Earth. The book describes briefly these benefits: Space colonies to house large populations; solar power from satellites; and the author's proposals of solar screens to reverse greenhouse warming, and of lunar gene banks for endangered species.

Astro-ecology can be extended also to more distant eons in the future, when energy will be determinant. The book assesses the potential amounts of life about various stars in the future galaxy. For these estimates, the book introduces the concept of time-integrated biomass (BIOTAint). In these terms, we can quantify the immense amounts of potential future life. Further, the book estimates the ultimate amount of life that can be physically possible in this universe, if all substance was converted to living matter and its supporting energy.

Astro-ecology shows that resources exist for an immense future. We can realize this future if we are guided by appropriate ethics. In the last chapters, the book describes a panbiotic ethics that can secure the immense potential of future life, and give our human existence a cosmic purpose. Along these lines, the new book addresses the science, technology and ethics of directed panspermia. The book is presented on a popular science level suitable for general readers and students, plus an Appendix with reprints of from leading space science journals: Icarus, Planetary and Space Science, and Journal of the British Interplanetary Society.

The author, Professor Michael Mautner, is a physical chemist with numerous publications in ion chemistry, astrochemistry, biophysics and astrobiology. He serves on the Editorial Board of Astrobiology and published popular science articles in The Futurist and Spaceflight. Since the 1970's, he has investigated and advocated seeding new solar systems with microorganisms, as a means to secure and expand life, and in 1995 founded the web-based Society for Life in Space (SOLIS, www.panspermia-society.com).

ABSTRACT DEADLINE EXTENDED FOR MARS SOCIETY CONVENTIONMars Society release6 June 2005

By vociferous popular demand, the abstract deadline for the 8th International Mars Society convention has been extended to June 30, 2005. There will be no further extensions. This year's conference will be held at the University of Colorado, Boulder, August 11-14, 2005. With a real human Moon-Mars exploration initative now finally underway, the conference promises to be our most exciting ever. So if you've got a paper to present, get your abstract in now. The revised call for papers is presented below. Registration for the conference is open at www.marssociety.org.

Call for papers

Presentations for the convention are invited dealing with all matters (science, engineering, politics, economics, public policy, etc.) associated with the

exploration and settlement of Mars. Abstracts of no more than 300 words should be sent by June 30, 2005 to: The Mars Society, P.O. Box 273, Indian Hills, CO 80454; or via email to: msabstracts@aol.com (e-mail submission preferred).

CASSINI UPDATESMultiple agencies' releases

Cassini Spies the Brightest Infrared Spot on TitanBy Lori Stiles, University of Arizona release, 25 May 2005

Something odd is happening on Titan just southeast of Xanadu. When the Cassini spacecraft flew by Titan on March 31 and again on April 16, its Visual and Infrared Mapping Spectrometer (VIMS) saw a spectacular, 300-mile-wide (500 kilometer) bright spot at long infrared wavelengths. The spot was just southeast of the continent-sized region called Xanadu. At 5-micron wavelengths—the longest, reddest wavelengths that VIMS sees—the red spot is the brightest area yet seen on Titan. The feature is the size and shape of West Virginia and 50 percent brighter than bright Xanadu.

The bright spot appears to be at the same location where Cassini's Imaging Science Subsystem (ISS) saw a bright, 345-mile (550-kilometer) wide semi-circle at visible wavelengths in December 2004. ISS saw the arc-shaped feature again at lower resolution during the February 2005 flyby. VIMS and ISS scientists combined their results for a complementary look at the infrared-bright feature on Saturn's moon, Titan.

The recently discovered infrared-bright spot on Titan (see Red Spot on Titan) is the type of enigmatic feature that is best investigated by putting together as many different types of complementary information as possible. Cassini's varied array of scientific instruments is equal to the task. This montage shows the spot in infrared wavelengths from the visual and infrared mapping spectrometer on the left, from the imaging science subsystem in the center, and a combination of both data sets on the right. Image credit: NASA/JPL/University of Arizona/Space Science Institute.

"At first glance, I thought the feature looked strange, almost out of place," said University of Arizona Professor Robert H. Brown of the Lunar and Planetary Laboratory (LPL), head of the VIMS team. "After thinking a bit, I speculated that it was a hot spot. In retrospect, that might not be the best hypothesis, but the spot is no less intriguing."

"The spot is maybe only 10 percent brighter at shorter, or bluer, infrared wavelengths," said Jason Barnes, a UA postdoctoral researcher who works with Brown. "But at these longer infrared wavelengths, this is a whopping difference in spectrum, or color. It's just the kind of thing we've been looking for. Unfortunately, we don't know yet what it is." The VIMS team suggests that the bright red spot is either a surface coloration—the strange reflection from an unusual patch of Titan's surface—or mountains, a cloud or a hot spot, Barnes said.

"It seems clear that ISS and VIMS are detecting the same basic feature on or controlled by Titan's surface," said ISS team scientist Alfred S. McEwen, who directs LPL's Planetary Imaging Research Laboratory. "This bright patch may be due to an impact event, landslide, cryovolcanism or atmospheric processes. Its distinct color and brightness suggests that it may have formed relatively recently."

"The feature seen by ISS looks like it's on the surface," said LPL's Elizabeth (Zibi) Turtle. Turtle is an associate on the Cassini imaging team, which is headed by UA adjunct Professor Carolyn Porco of the Space Science Institute

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in Boulder, CO. "It's possible that VIMS is seeing a cloud that is topographically controlled by something on the surface, and that this weird, semi-circular feature is causing this cloud."

Other bright spots have been seen on Titan, but all have been transient features that move or disappear within hours, and they have different spectral (color) properties than this feature has. If the feature is a cloud, it reflects light in a way that is uncharacteristic of clouds, Brown said.

Barnes checked VIMS images from previous Titan passes, in July and October 2004, and found a bright spot consistent with the size and shape with the spot first identified by VIMS images from the March 2005 flyby. "If the spot is a cloud, then its longevity and stability imply that it is controlled by the surface," he said. "Such a cloud might result from airflow across low mountains or outgassing caused by geologic activity."

The bright red spot could be reflections from a patch of terrain made up of some exotic surface material. "Titan's surface seems to be mostly dirty ice. The bright spot might be a region with different surface composition, or maybe a thin surface deposit of non-icy material," Barnes said.

Scientists have also considered that the spot might be mountains. If so, they'd have to be much higher than the 100-meter-high (300-foot) hills Cassini's radar altimeter has so far seen. Scientists doubt that Titan's crust could support such high mountains. Another possibility is that the bright region is a "hot" spot, an area warmed by a recent asteroid impact or warmed by a mixture of water ice and ammonia oozing out of an ice volcano over the colder surrounding terrain. The VIMS team will be able to test the hot spot hypothesis on the July 2, 2006 Titan flyby, when VIMS will take nighttime images of the area. If the spot glows at night, researchers will know it's hot.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov. For additional images visit the VIMS page at http://wwwvims.lpl.arizona.edu and the Cassini imaging team homepage http://ciclops.org.

Images online at:VIMS - http://wwwvims.lpl.arizona.edu/ISS - http://ciclops.orgCassini - http://saturn.jpl.nasa.gov/

Cassini Significant Events for 19-25 May 2005NASA/JPL release, 27 May 2005

The most recent spacecraft telemetry was acquired Wednesday from the Goldstone tracking station. 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 Radio Science Subsystem team performed the second of eight occultation experiments this week. Instruments from the Optical Remote Sensing group participated in joint studies of Enceladus and the rings at 0 deg. phase, performed a series of stellar occultation activities, observed the apparent passage of the star CW Leo through the atmosphere of Saturn to obtain composition and chemistry information at high latitudes, and performed Far-Infrared hemisphere mapping of Saturn and several radial scans of the rings to obtain sub-millimeter and temperature measurements. Finally, instruments from the Magnetospheric and Plasma Science group performed a high-resolution study of bow shocks and other magnetospheric boundaries.

Thursday, May 19 (DOY 139):

A decision was made by Program Management to go with the new Cassini adaptation of the Configuration Management system that was demonstrated last week at the combined Cassini Design Team/Instrument Operations Working Group Meeting. The system will be ready for Program use in September 2005. A schedule and plan are being developed to bring the system to operational readiness. Training is planned for users in the month of August, both at the Project Science Group Meeting and at JPL.

The Visual and Infrared Mapping Spectrometer (VIMS) was one of the instruments that performed an occultation observation of star CW Leo as it passed behind the Saturn limb and one of Omicron Ceti as it passed behind the rings. Both observations were the first of their kind by VIMS and the science team reports stunningly successful tracking and data quality.

A Ground Software Monthly Management Review was held to review status for the June 2005 delivery. All teams reported they are on-track and have no issues. A recently discovered problem in the Telemetry, Tracking, Command & Data Management system version 29.1 telemetry software will require a redelivery with version V29.1.1. Since all Cassini-developed software was tested on the previous version, we will deploy the June delivery on V28.1.1, and then upgrade the "core" system when it is delivered and tested. The first of two S11 live Inertial Vector Propagator updates began execution very late on Thursday.

Friday, May 20 (DOY 140):

Instrument Operations (IO) reported that the Imaging Science Subsystem (ISS) has completed a set of reports containing metadata describing the contents of the first set of archive DVDs being produced by the science team. These reports are derived from the IO/ Multi-mission Image Processing Laboratory database.

Saturday, May 21 (DOY 141):

In the wee hours of the morning the first live moveable block in S11 began execution and ran for about 12 hours. During this time the Radio Science Subsystem (RSS) measured the properties of Saturn's rings and atmosphere by performing a diametric radio occultation experiment, and the Cosmic Dust Analyzer (CDA) measured the dust flux and particle composition during the Enceladus Orbit Crossing.

There were non-targeted flybys of the Saturnian satellites Atlas, Prometheus, and Enceladus. A non-targeted flyby is one that occurs without any maneuvers and observes satellites that just happen to be in a place that can be seen by Cassini. Typically the altitudes are higher than for targeted flybys, up to 100,000 km. The altitude will vary as the reference trajectory changes. Some non-targeted flybys may disappear as the trajectory changes, and others may suddenly emerge.

Just to complete the picture, a targeted flyby is one that uses maneuvers to achieve the desired altitude, and the flyby altitude is fixed and does not change even when the reference trajectory changes. Targeted flybys are usually less than 3000 km in altitude.

Sunday, May 22 (DOY 142):

Today and for the next two days, Uplink Operations will be sending new versions of instrument flight software up to the spacecraft for Cassini Plasma Spectrometer (CAPS), CDA, and ISS.

Monday, May 23 (DOY 143):

Mission Planning posted a report from last week's T5 Titan Atmosphere Model Working Group meeting to the Cassini Internal web site. The results are somewhat preliminary but the conclusions are valid for picking a new lowest Titan safe altitude.

In a press release issued today it was reported that the Cassini spacecraft has obtained the most detailed look ever at Saturn's rings, including the B ring, which has eluded previous robotic explorers. Its structure seems remarkably different from its two neighbors, rings A and C. During the May 2-3 Radio Science Occultation experiment, Cassini mapped this structure with a clarity never before available.

During a radio occultation, Cassini sends a radio signal from the spacecraft through the rings to Earth. Scientists then watch how the strength, phase, and amplitude of the radio signal is affected as the signal passes through ring material. The denser a ring is, the weaker the signal received. The experiment helps scientists map the distribution of the amount of ring material and determine the ring particle sizes.

The Cassini tour was designed specifically to optimize the geometry of the first radio occultation experiment and seven other occultations scheduled from May to September 2005. These observations are at the heart of Cassini's fundamental science objectives of characterizing and understanding Saturn and its ring system. For more information on this press release go to http://saturn.jpl.nasa.gov. An image of Saturn's wave maker moon is Astronomy Picture of the Day today.

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Tuesday, May 24 (DOY 144):

Cassini Outreach participated in a Career Day at Temple City High School.NASA stickers and Cassini bookmarks were distributed while members of the Outreach team spoke to small groups of students.

Cassini Outreach received an amazing thank you card in the mail from Hugo Reid School in Arcadia, CA this week, in response to a mailing of Cassini outreach material. Each student in the class wrote a thank you note on one of 27 paper "students" in a cutout chain. This thank you card, of 27 yellow students holding hands, is proudly on display in the Cassini outreach offices.

Wednesday, May 25 (DOY 145):

The S11 leads uplinked checkout exercises for the new CAPS and CDA Flight Software. The CAPS checkout will execute today, and CDA will perform theirs on Monday May 30.

In a second press release this week it was reported that Saturn's moon Titan shows an unusual bright spot. The 483-kilometer-wide region is approximately the size and shape of West Virginia, and is located just southeast of the bright region called Xanadu. Other bright spots have been seen on Titan, but all have been transient features that move or disappear within hours, and have different spectral properties than this feature. This spot is persistent in both its color and location. For more information link to http://saturn.jpl.nasa.gov. A false-color picture of Saturn's rings is Astronomy Picture of the Day today.

Cassini Significant Events for 26-31 May 2005NASA/JPL release, 3 June 2005

The most recent spacecraft telemetry was acquired Tuesday from the Goldstone tracking station. 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.

On-board science activities this week include a joint study by the Optical Remote Sensing instruments of Saturn's atmosphere and the measurement of tropospheric temperatures. The Ultraviolet Imaging Spectrograph (UVIS), Imaging Science Subsystem (ISS), and Visual and Infrared Mapping Spectrometer (VIMS) will attempt to detect flashes from meter-sized interplanetary impacts on the rings.

Meanwhile, the Cassini Plasma Spectrometer (CAPS), Radio and Plasma Wave Science Subsystem (RPWS), Magnetospheric Imaging Instrument (MIMI), and Magnetometer Subsystem (MAG) will perform a high-resolution study of bow shocks and other magnetospheric boundaries.

Thursday, May 26 (DOY 146):

JPL had a visit last week from the new NASA Administrator Mike Griffin.Cassini was pleased to be able to provide Mr. Griffin with a visit to the Cassini Ace console. This is the station from where all our commands are

sent to the spacecraft. In addition, outreach personnel presented Reading, Writing, and Rings, the Cassini formal education initiative. RWR helps prepare children for standardized language arts tests while engaging our nation's youngest learners and their teachers with the science, math, and technology of NASA's exploration in a language arts format.

A string of three of Saturn's icy moons encircles the planet in this Cassini image. Visible here are: Mimas (397 kilometers, or 247 miles across) near lower right; Janus (181 kilometers, or 113 miles across) below the F ring; and Enceladus (505 kilometers, or 314 miles across) at lower left. The scene has been brightened to increase the moons' visibility. Image credit: NASA/JPL/Space Science Institute.

Outreach has recently beefed up the Cassini web site. If you go to http://saturn.jpl.nasa.gov/science/moons/index.cfm and scroll to the bottom of the third paragraph you will find a link to New Discoveries. From this location you can read about the new moons that have been recently observed orbiting Saturn.

In this fabulous close-up, Cassini peers directly through regions of the A, B and C rings (from top to bottom here) to glimpse shadows of the very same rings cast upon the planet's atmosphere. Near the top, shadows cast by ringlets in the Cassini division (center) look almost like a photo negative. Image credit: NASA/JPL/Space Science Institute.

A kick-off meeting was held today for the S11 Live Inertial Vector Propagator update and Live Movable Block process. As part of this process, Navigation released a special Orbit Determination solution for use for the next Radio Science Occultation. Teams have the rest of today and tomorrow to review

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the files and be prepared to present at Tuesday's Go/No Go meeting. UPDATE: Tuesday's meeting gave it a go!

CAPS performed a checkout of their new flight software, the Spacecraft Operations Office uplinked the new ACS 8.7.2 flight software parameter patch, and VIMS used the Automated Sequence Processor to uplink instrument commands independently of the sequence leads.

For the second year, Cassini Outreach attended the Los Angeles Coliseum Street Elementary School Career Day. This year three third grade classes and one fifth grade class were visited. Each of the two dozen career day volunteers was introduced at morning assembly and many students cheered when they heard a visitor from JPL would talk about career opportunities. NASA and Saturn stickers and Cassini bookmarks were handed out to the kids. Student volunteers received the stickers plus a Cassini poster. Interested teachers will follow up to receive Cassini's Reading, Writing and Rings literacy program material or assistance in using the material in their classroom.

Saturn's brightly sunlit moon Rhea commands the foreground in this image from Cassini. The planet's splendid rings are discernible in the background. Rhea is 1,528 kilometers (949 miles) across. The spacecraft was just above the ringplane when it acquired this image, and thus captured the darkened appearance of the dense B ring when viewed with sunlight filtered through the rings. From this perspective, bright areas in the rings are regions of low density, containing very small particles that effectively scatter light toward Cassini. North on Rhea is up and rotated about 25 degrees to the left. This view shows principally the anti-Saturn hemisphere on Rhea. The right side of Rhea is overexposed. Image credit: NASA/JPL/Space Science Institute.

Friday, May 27 (DOY 147):

A picture of Titan's "Odd Spot" is Astronomy Picture of the Day today.

Uplink Operations sent commands to the spacecraft for a Reaction Wheel Assembly bias overlay, an Ion and Neutral Mass Spectrometer instrument flight software patch and memory readout, a flight software checkout for the Cosmic Dust Analyzer, and a Ka-band equipment power on/off for Radio Science.

All products were received for the S14 preliminary port delivery as part of the Science Operations Plan Update process. The merge has been completed and all products placed in the file repository for teams to review.

Monday, May 30 (DOY 150):

Rhea's "great white spot" was Astronomy Picture of the Day on Sunday, May 29.

Today is apoapsis and the start of Cassini's ninth orbit around Saturn. CDA ran a checkout of their new flight software today. Everything went well.

Tuesday, May 31 (DOY 151):

Uplink Operations sent three sets of files to the spacecraft for the VIMSSSR Instrument Expanded Block (IEB) load. Initialization files, the IEBload itself, and cleanup and memory readout (MRO) files were sent. All files reached the spacecraft with no errors.

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, CA, manages the mission for NASA's Science Mission Directorate, Washington, DC. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team is based at the Space Science Institute in Boulder, CO. The Visual and Infrared Mapping Spectrometer team is based at The University of Arizona in Tucson.

Contacts:Robert H. BrownPhone: 520-626-9045E-mail: rhb@lpl.arizona.edu

Jason BarnesPhone: 520-626-1356E-mail: jbarnes@barnesos.net

Alfred S. McEwenPhone: 520-621-4573E-mail: mcewen@lpl.arizona.edu

Elizabeth (Zibi) TurtlePhone: 520-621-8284E-mail: turtle@lpl.arizona.edu

Lori Stiles, UA News ServicesPhone: 520-626-4402 E-mail: lstiles@u.arizona.edu

Preston Dyches, CICLOPS/Space Science InstitutePhone: 720-974-5859 E-mail: media@ciclops.org

Carolina Martinez, Jet Propulsion Laboratory Media RelationsPhone: 818-354-9382E-mail: Carolina.Martinez@jpl.nasa.gov

Additional articles on this subject are available at:http://www.astrobio.net/news/article1576.htmlhttp://www.spacedaily.com/news/cassini-05zzd.htmlhttp://spaceflightnow.com/cassini/050525titanspot.htmlhttp://www.universetoday.com/am/publish/mystery_spot_titan.htmlhttp://www.universetoday.com/am/publish/cassini_density_rings.htmlhttp://www.universetoday.com/am/publish/bend_saturn_rings.htmlhttp://www.universetoday.com/am/publish/view_through_rings.html

NASA'S SPACE EYES FOCUS ON DEEP IMPACT TARGET NASA release 05-1392 June 2005

On July 4, NASA's Deep Impact spacecraft will attempt an extraordinarily daring encounter with the far-flung comet Tempel 1 hurtling through space at tens of thousands of miles per hour. As if that is not challenging enough, the comet's size, shape and other characteristics are not entirely known.

Two of NASA's eyes in the sky, the Spitzer and Hubble Space Telescopes, helped scientists prepare for the comet encounter. From their orbits high above Earth, the telescopes watched Tempel 1 in early 2004. Together they came up with the best estimates of the comet's size, shape, reflectivity and

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rotation rate. The data may help Deep Impact snap pictures of the dramatic rendezvous and increase the probability of making contact with the comet.

"Even tiny adjustments to our model of Tempel 1 are crucial to hitting the target and setting camera exposure times," said Dr. Carey Lisse, Johns Hopkins University Applied Physics Laboratory, Laurel, MD. Lisse is team leader for the Tempel 1 Spitzer studies.

Previous observations of Tempel 1 taken with ground-based telescopes indicated the comet is dark and oblong, with a width of a few miles. Spitzer and Hubble refined these measurements, revealing a matte black comet approximately 8.7 by 2.5 miles, or roughly one-half the size of Manhattan Island, NY.

"Spitzer was crucial in pinning down the comet's size," said Dr. Michael A'Hearn, University of Maryland, College Park. He is principal investigator for Deep Impact and the Hubble observations. "We'll know exactly what it looks like when we get there," he said.

The Deep Impact spacecraft was launched on January 12, 2005. Its mission is to study the primordial soup of our solar system, which is sealed away inside comets. On July 3, as it approaches Tempel 1, the spacecraft will separate into two parts. The impactor will attempt the tricky task of placing itself in the path of the speeding snowball, while the second part, the flyby spacecraft, swings around for a ringside view.

After the impactor is released, its specialized software will steer it toward the sunlit portion of Tempel 1's nucleus. To program the software, mission planners at NASA's Jet Propulsion Laboratory (JPL) needed to know the size and reflectivity of Tempel 1's surface. Since its surface can't be observed directly from Earth, scientists turned to Spitzer's infrared eyes to measure its size.

When viewing a comet in visible light from very far away, only reflected sunlight can be seen, so a big, dark comet can look the same as a highly reflective, small comet. In infrared light, a comet's radiated heat is measured, providing a direct look at its size. Once the size of Tempel 1 was known, scientists could calculate surface reflectivity. They calculated the amount of reflected, visible light observed by Hubble and found Tempel 1 reflects only four percent of the sunlight that falls on it.

"Knowing the reflectivity also tells us how to set up our cameras," Lisse said. "Like photographers, it's important for us to know our subject before the shoot."

Tempel 1's shape and two-day rotation rate were derived from long-term observations made by various telescopes, including Hubble, Spitzer and the University of Hawaii's 2.2-meter telescope at Mauna Kea.

In addition to the flyby spacecraft images, at least 30 telescopes around the world, including Spitzer, Hubble and the Chandra X-ray Observatory, will be watching the dramatic impact. By analyzing the material blown out of the

interior of the comet, this global network of telescopes will assemble a list of the raw ingredients that went into making the planets in our solar system.

JPL manages the Deep Impact mission for NASA. For information about NASA and the Deep Impact mission on the Web, visit http://www.nasa.gov/home/index.html, http://www.spitzer.caltech.edu/spitzer, http://hubblesite.org/news/ or http://deepimpact.jpl.nasa.gov/.

Contacts:Dolores Beasley/Marta MetelkoNASA Headquarters, Washington, DCPhone: 202-358-1753/1642

Whitney ClavinJet Propulsion Laboratory, Pasadena, CAPhone: 818-354-4673

Additional articles on this subject are available at:http://www.astrobio.net/news/article1585.htmlhttp://www.space.com/scienceastronomy/050602_comet_tempel1.htmlhttp://www.spacedaily.com/news/comet-05o.htmlhttp://www.spacedaily.com/news/comet-05p.htmlhttp://spaceflightnow.com/news/n0506/02deepimpact/http://www.universetoday.com/am/publish/great_observatories_deep_impact.html

HOW TO WATCH JULY 4 COMET IMPACTBy Joe RaoFrom Space.com3 June 2005

In early July, NASA's Deep Impact spacecraft will deploy a tiny impactor to smash into the nucleus of a small comet. The idea is to excavate a sizable crater and provide valuable insight into the true nature of comets. For skywatchers here on Earth, it should also produce a large cloud of ejected material that should cause the comet to significantly brighten enough to become visible with binoculars and perhaps even with the unaided eye. The comet that has been chosen for the task was discovered by a Frenchman in the mid-19th century. Known as Comet Tempel 1, it already has a rather checkered history. Soon, however, it will go down in history books.

Read the full article at http://www.space.com/spacewatch/050603_deep_impact.html.

MER UPDATESNASA/JPL releases

NASA's Rovers Continue Martian MissionsNASA/JPL release 2005-085, 24 May 2005

NASA's Mars rover Opportunity is trying to escape from a sand trap, while its twin, Spirit, has been busy finding new clues to a wet and violent early martian history. "Spirit has finally found the kind of geology you can really sink your teeth into," said Dr. Steve Squyres of Cornell University, Ithaca, NY. He is principal investigator for the Mars rovers' science instruments. According to Squyres, multiple layers of rock in the hills Spirit is exploring suggest successive deposits of water-altered explosive debris. Spirit, inside Mars' Gusev Crater, had to share the spotlight with the drama provided by Opportunity on the martian Meridiani plains. The rover has been hindered by soft sand for nearly three weeks. Traction is difficult in the ripple-shaped dune of windblown dust and sand that Opportunity drove into on April 26. Since it began trying to get out, the rover has advanced only 11 inches. Without the slippage caused by the rover's wheels spinning in the soft sand, Opportunity could have driven 157 feet. "If Opportunity gets free, its next task will be examining the site to give the rover team a better understanding of how this ripple differs from dozens Opportunity easily crossed," said Jim Erickson. He is project manager for the Mars Exploration Rover project at NASA's Jet Propulsion Laboratory, Pasadena, CA.

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This mosaic of 24 frames from the microscopic imager on NASA's Mars Exploration Rover Spirit shows the texture of a target called "Keystone" on the "Methuselah" outcrop of layered rock on "Husband Hill" inside Mars' Gusev Crater. The images were taken on Spirit's 469th martian day, or "sol (April 28, 2005). The target area shows fine layers that may have been deposited by wind or water. The individual frames are each 3 centimeters (1.2 inches) across and they overlap slightly in this array of six frames horizontally by four frames vertically. The target was fully shadowed when the images were acquired. The scale of the images (31 microns or one one-thousandth of an inch per pixel) allows features as small as 0.1 millimeter (four one-thousandths of an inch) to be resolved. Image credit: NASA/JPL/Cornell/USGS.

The rovers have worked under harsh martian conditions longer than expected. They have been studying geology on opposite sides of Mars for more than a year since successfully completing their three-month primary missions. Shortly after landing in January 2004, Opportunity found layered bedrock bearing geological evidence of a shallow ancient sea. More than one year later, Spirit found extensive layered bedrock after driving more than two miles and climbing into the "Columbia Hills." Squyres said, "In the last few weeks, we have gone from a state of confusion about the geology of the "Columbia Hills" to having real stratigraphic sequence and a powerful working hypothesis for the history of these layers." For several months, Spirit climbed a flank of "Husband Hill," the tallest in the range. The slope closely matched the angle of underlying rock layers, which made the layering difficult to detect. Spirit reached an intermediate destination, dubbed "Larry's Lookout," then continued uphill and looked back. "That was the critical moment, when it all began falling into place," Squyres said. "Looking back downhill, you can see the layering, and it suddenly starts to makes sense." Spirit has been examining rocks in a series of outcrops called "Methuselah," "Jibsheet" and "Larry's Lookout." Some of the rocks contain the mineral ilmenite, not found previously by Spirit. "Ilmenite is a titanium-iron oxide formed during crystallization of magma," said Dr. Dick Morris, a rover science-team member at NASA's Johnson Space Center, Houston. "Its occurrence is evidence for diversity in the volcanic rocks in the Gusev region." Rocks from different layers share compositional traits, high in titanium and low in chromium, which suggests a shared origin. However, the degree to which minerals in rocks have been chemically altered by exposure to water or other processes varies greatly from outcrop to outcrop. The textures also vary. At Methuselah, rocks have thin laminations revealed by Spirit's microscopic imager. At Jibsheet, they are built of bulbous grains packed together. At Larry's Lookout, the rocks are massive, with little fine-scale structure. "Our best hypothesis is we're looking at a stack of ash or debris that was explosively erupted from volcanoes and settled down in different ways," Squyres said. "We can't fully rule out the possibility the debris was generated in impact explosions instead of volcanic ones. But we can say, once upon a time, Gusev was a pretty violent place. Big, explosive events were happening, and there was a lot of water around."

Rover-team scientists described the robot explorers' activities today at the spring meeting of the American Geophysical Union in New Orleans. For images and information about the rovers and their discoveries, visit http://www.nasa.gov/vision/universe/solarsystem/mer_main.html. For information about NASA and agency programs on the web, visit http://www.nasa.gov/home/index.html.

NASA's Opportunity Rover Rolls Free on MarsNASA/JPL release, 6 June 2005 Engineers and mission managers for NASA's Mars Exploration Rover mission cheered when images from the martian surface confirmed Opportunity had successfully escaped from a sand trap. From about 174 million kilometers away (about 108 million miles), the rover team at NASA's Jet Propulsion Laboratory, Pasadena, Calif., had worked diligently for nearly five weeks to extricate the rover. The long-distance roadside assistance was a painstaking operation to free all six wheels of the rover, which were mired up to their rims in the soft sand of a small martian dune.

Opportunity's view after maneuvering out of sandtrap. Image credit: NASA/JPL.

"After a nerve-wracking month of hard work, the rover team is both elated and relieved to finally see our wheels sitting on top of the sand instead of half buried in it," said Jeffrey Biesiadecki, a JPL rover mobility engineer. Traction was difficult in the ripple-shaped dune of windblown dust and sand that Opportunity drove into on April 26. In the weeks following, the rover churned 192 meters (629 feet) worth of wheel rotations before gaining enough traction to actually move one meter (about three feet). The rover team directed the drives in cautious increments from May 13 through June 4. "We did careful testing for how to get Opportunity out of the sand. Then we patiently followed the strategy developed from the testing, monitoring every step of the way," Biesiadecki said. "We hope to have Opportunity busy with a full schedule of scientific exploration again shortly." Opportunity's next task is to examine the site to provide a better understanding of what makes that ripple different from the dozens of similar ones the rover easily crossed. "After we analyze this area, we'll be able to plan safer driving in the terrain ahead," said JPL's Jim Erickson, rover project manager. Both Spirit and Opportunity have worked in harsh martian conditions much longer than anticipated. They have been studying geology on opposite sides of Mars for more than a year of extended missions since successfully completing their three-month primary missions in April 2004.

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"The first thing we're going to do is simply take a hard look at the stuff we were stuck in," said Dr. Steve Squyres of Cornell University, Ithaca, NY. He is the principal investigator for the Mars rovers' science instruments. "After that, we will begin a cautious set of moves to get us on our way southward again. South is where we think the best science is, so that's still where we want to go." Shortly after landing in January 2004, Opportunity found layered bedrock that bore geological evidence for a shallow ancient sea. Spirit did not find extensive layered bedrock until more than a year later, after driving more than two miles and climbing into a range of hills known as "Columbia Hills." Images and information about the rovers and their discoveries are available on the Web at http://www.nasa.gov/vision/universe/solarsystem/mer_main.html and http://www.jpl.nasa.gov/missions/mer/. For information about NASA and agency programs on the Web, visit http://www.nasa.gov/home/index.html.

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

Natalie GodwinJet Propulsion Laboratory, Pasadena, CAPhone: 818-354-0850 Dolores BeasleyNASA Headquarters, Washington, DCPhone: 202-358-1753

Additional articles on this subject are available at:http://www.astrobio.net/news/article1572.htmlhttp://www.astrobio.net/news/article1578.htmlhttp://www.astrobio.net/news/article1590.htmlhttp://www.marsdaily.com/news/mars-mers-05zzg.htmlhttp://www.marsdaily.com/news/mars-mers-05zzi.htmlhttp://www.marsdaily.com/news/mars-mers-05zzl.htmlhttp://www.space.com/missionlaunches/opportunity_free_050604.htmlhttp://www.spacedaily.com/news/mars-mers-05zze.htmlhttp://www.spacedaily.com/news/mars-mers-05zzk.htmlhttp://spaceflightnow.com/news/n0505/24mera/http://www.universetoday.com/am/publish/opportunity_working_free.htmlhttp://www.universetoday.com/am/publish/oppy_free_dune.html

MARS EXPRESS: ANCIENT FLOODS ON MARSESA release1 June 2005

These images, taken by the High Resolution Stereo Camera (HRSC) aboard ESA's Mars Express spacecraft, show a large depression called Iani Chaos and the upper reaches of a large outflow channel called Ares Vallis. Image strips were taken in October 2004, during three orbits from a 350-kilometer altitude, with a resolution of 15 meters per pixel. The strips have then been matched to a mosaic that covers an area from 17.5º western longitude to 3º North.

Disrupted pattern of rock blocks between Iani Chaos and Ares Vallis. Image credit: ESA/DLR/FU Berlin (G. Neukum).

The Iani Chaos depression—180 kilometers long and 200 kilometres wide—is connected to the beginning of Ares Vallis by a 100-kilometer wide transition zone. From here, Ares Vallis continues its course for about 1400 kilometers through the ancient Xanthe Terra highlands, bordered by valley flanks up to 2000 meters high. Eventually Ares Vallis empties into Chryse Planitia.

These images help illuminate the complex geological history of Mars. Ares Vallis is one of several big outflow channels on Mars in this region that formed billions of years ago. Many surface features suggest that erosion of large water flows had carved Ares Vallis in the martian landscape. Most likely, gigantic floods ran downhill, carving a deep canyon into Xanthe Terra. Rocks eroded from the valley flanks were milled into smaller fractions and transported in the running water. Finally this sedimentary load was deposited far north at the mouth of Ares Vallis in the Chryse plains, where NASA's Mars Pathfinder landed in 1997 to search for traces of water with its small Sojourner rover.

Signs of erosion by water flows in Ares Vallis. Image credit: ESA/DLR/ FU Berlin (G. Neukum).

The scenes displayed in the images show the transition zone between Iani Chaos and Ares Vallis. A chaotic distribution of individual blocks of rock and hills forms a disrupted pattern. These "knobs" are several hundred meters high. Scientists suggest that they are remnants of a preexisting landscape that collapsed after cavities had formed beneath the surface. The elongated curvature of features extending from south to north along with terraces, streamlined "islands" and the smooth, flat surface in the valley centre are strong hints that it was running water that carved the valley. Ice stored in possible cavities in the martian highland might have been melted by volcanic heat. Pouring out, the melting water would have followed the pre-existing topography to the northern lowlands.

Perspective close-up view of outflow signatures in Ares Vallis. Image credit: ESA/DLR/FU Berlin (G. Neukum).

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A hundred kilometers further, a ten-kilometer-wide valley arm merges into Ares Vallis from the west. Large amounts of water originating from Aram Chaos (outside the image) joined the stream of Ares Vallis. Fan-shaped deposits on the valley floor are the remnants of landslides at the northern flanks. At the freshly eroded cliffs possible lava layers are visible: such layers are found almost everywhere in Xanthe Terra. Further downstream, another valley branch enters Ares Vallis from the east after passing through an eroded impact crater in Xanthe Terra. West of Ares Vallis, a subtler riverbed is running parallel to the main valley.

A ten-kilometer-wide valley arm merges in Ares Vallis from the west. Image credit: ESA/DLR/FU Berlin (G. Neukum).

Cliffs and possible lava layers in Xanthe Terra. Image credit: ESA/ DLR/FU Berlin (G. Neukum).

A black-and-white overview was imaged by the nadir (vertical view) channel. The orthogonal color scenes were processed using the three color channels and the nadir channel. The perspective views were derived from the digital terrain model based on the stereo channels, and then combined with the color channels. The anaglyph or stereoscopic image was processed from the nadir and one stereo channel. Image resolution has been reduced for use on the internet. The flyover video is based on the digital terrain model from the stereo channels and the color data.

The High Resolution Stereo Camera (HRSC) experiment on the ESA Mars Express Mission is led by Principal Investigator (PI) Professor Dr. Gerhard Neukum who is also responsible for the technical design of the camera. The science team of the experiment consists of 45 Co-Investigators from 32 institutions and ten nations. The camera was developed at the German Aerospace Centre (DLR) under the leadership of the PI and constructed in cooperation with industrial partners (EADS-Astrium, Lewicki Microelectronic GmbH and Jena-Optronik GmbH). The experiment on Mars Express is operated by the DLR Institute of Planetary Research through ESA/ESOC. The systematic processing of the HRSC image data is carried out at DLR.

The scenes shown here were processed by the PI-group at the Institute of Geosciences of the Freie Universitaet Berlin in cooperation with DLR Institute of Planetary Research in Berlin. The movie has been processed at DLR.

Global view of the area including Iani Chaos and Ares Vallis. Image credit: ESA/DLR/FU Berlin (G. Neukum).

Color and grayscale vertical views of Iani Chaos and Ares Vallis. Image credit: ESA/ DLR/FU Berlin (G. Neukum).

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Read the original news release at http://www.esa.int/SPECIALS/Mars_Express/SEMIKO0DU8E_0.html.

Additional articles on this subject are available at:http://www.astrobio.net/news/article1584.htmlhttp://www.marsdaily.com/news/marsexpress-05s.htmlhttp://www.space.com/imageoftheday/image_of_day_050606.htmlhttp://www.universetoday.com/am/publish/ancient_floods_mars.html

MARS GLOBAL SURVEYOR IMAGESNASA/JPL/MSSS releases19 May - 1 June 2005

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

MGS Sees Mars Odyssey and Mars Express (Released 19 May 2005)http://www.msss.com/mars_images/moc/2005/05/19

Gullied Slope (Released 20 May 2005)http://www.msss.com/mars_images/moc/2005/05/20

Martian Valley (Released 21 May 2005)http://www.msss.com/mars_images/moc/2005/05/21

Tithonium Yardangs (Released 22 May 2005)http://www.msss.com/mars_images/moc/2005/05/22

4 Mars Years of Change (Released 23 May 2005)http://www.msss.com/mars_images/moc/2005/05/23

Mars at Ls 211 Degrees (Released 24 May 2005)http://www.msss.com/mars_images/moc/2005/05/24

Looking Into a Trough (Released 25 May 2005)http://www.msss.com/mars_images/moc/2005/05/25

Aram Chaos Complexity (Released 26 May 2005)http://www.msss.com/mars_images/moc/2005/05/26

Young Impact (Released 27 May 2005)http://www.msss.com/mars_images/moc/2005/05/27

Slope-Streaked Knob (Released 28 May 2005)http://www.msss.com/mars_images/moc/2005/05/28

Defrosting Features (Released 29 May 2005)http://www.msss.com/mars_images/moc/2005/05/29

East Candor Outcrops (Released 30 May 2005)http://www.msss.com/mars_images/moc/2005/05/30

Mars at Ls 211 Degrees (Released 31 May 2005)http://www.msss.com/mars_images/moc/2005/05/31

Channel near Olympus (Released 01 June 2006)http://www.msss.com/mars_images/moc/2005/06/01

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 releases23 May - 3 June 2005

Meridiani (Released 23 May 2005)http://themis.la.asu.edu/zoom-20050523a.html

More Meridiani (Released 24 May 2005)http://themis.la.asu.edu/zoom-20050524a.html

Elysium Mons (Released 25 May 2005)http://themis.la.asu.edu/zoom-20050525a.html

Cratered Acidalia Planitia (Released 26 May 2005)http://themis.la.asu.edu/zoom-20050526a.html

Acidalia Planitia Channel Margin (Released 27 May 2005)http://themis.la.asu.edu/zoom-20050527a.html

Wind Streaks in Syrtis Major (Released 30 May 2005)http://themis.la.asu.edu/zoom-20050530a.html

Elysium Windstreaks (Released 31 May 2005)http://themis.la.asu.edu/zoom-20050531a.html

Alba Patera Windstreaks (Released 1 June 2005)http://themis.la.asu.edu/zoom-20050601A.html

Olympus Mons Windstreaks (Released 2 June 2005)http://themis.la.asu.edu/zoom-20050602A.html

IR Windstreaks (Released 3 June 2005)http://themis.la.asu.edu/zoom-20050603A.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.

NASA'S PHOENIX MARS MISSION BEGINS LAUNCH PREPARATIONSNASA release 05-1412 June 2005

NASA has given the green light to a project to put a long-armed lander on to the icy ground of the far-northern martian plains. NASA's Phoenix lander is designed to examine the site for potential habitats for water ice, and to look for possible indicators of life, past or present. Today's announcement allows the Phoenix mission to proceed with preparing the spacecraft for launch in August 2007. This major milestone followed a critical review of the project's planning progress and preliminary design, since its selection in 2003. Phoenix is the first project in NASA's Mars Scout Program of competitively selected missions. Scouts are innovative and relatively low-cost complements to the core missions of the agency's Mars exploration program.

"The Phoenix Mission explores new territory in the northern plains of Mars analogous to the permafrost regions on Earth," said the project's principal investigator, Peter Smith of the University of Arizona, Tucson. "NASA's confirmation supports this project and may eventually lead to discoveries relating to life on our neighboring planet."

Phoenix is a stationary lander. It has a robotic arm to dig down to the martian ice layer and deliver samples to sophisticated analytical instruments on the lander's deck. It is specifically designed to measure volatiles, such as water and organic molecules, in the northern polar region of Mars. In 2002, NASA's Mars Odyssey orbiter found evidence of ice-rich soil very near the surface in the arctic regions.

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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. As the Mars program artist, Mr. Waste has created artwork for several Mars missions.

Like its namesake, Phoenix rises from ashes, carrying the legacies of two earlier attempts to explore Mars. The 2001 Mars Surveyor lander, administratively mothballed in 2000, is being resurrected for Phoenix. Many of the scientific instruments for Phoenix were built or designed for that mission or flew on the unsuccessful Mars Polar Lander in 1999.

"The Phoenix team's quick response to the Odyssey discoveries and the cost-saving adaptation of earlier missions' technology are just the kind of flexibility the Mars Scout Program seeks to elicit," said NASA's Mars Exploration Program Director, Doug McCuistion.

"Phoenix revives pieces of past missions in order to take NASA's Mars exploration into an exciting future," said NASA's Director, Solar System Division, Science Mission Directorate, Andrew Dantzler.

The cost of the Phoenix mission is $386 million, which includes the launch. The partnership developing the Phoenix mission includes the University of Arizona; NASA's Jet Propulsion Laboratory (JPL), Pasadena, CA; Lockheed Martin Space Systems, Denver, CO; and the Canadian Space Agency, which is providing weather-monitoring instruments.

"The confirmation review is an important step for all major NASA missions," said JPL's Barry Goldstein, project manager for Phoenix. "This approval essentially confirms NASA's confidence that the spacecraft and science instruments will be successfully built and launched, and that once the lander is on Mars, the science objectives can be successfully achieved."

Much work lies ahead. Team members will assemble and test every subsystem on the spacecraft and science payload to show they comply with design requirements. Other tasks include selecting a landing site, which should be aided by data provided by the Mars Reconnaissance Orbiter launching in August, and preparing to operate the spacecraft after launch.

JPL, a division of the California Institute of Technology, Pasadena, manages Phoenix for NASA's Science Mission Directorate. For information about NASA and agency programs on the Web, visit http://www.nasa.gov/home/index.html. For information about the Phoenix Mission to Mars on the Web, visit http://phoenix.lpl.arizona.edu.

Contacts:Dolores BeasleyNASA Headquarters, Washington, DCPhone: 202-358-1753

Guy WebsterJet Propulsion Laboratory, Pasadena, CAPhone: 818-354-6278

Lori StilesUniversity of Arizona, TucsonPhone: 520-626-4402

Additional articles on this subject are available at:http://www.astrobio.net/news/article1586.htmlhttp://www.marsdaily.com/news/mars-future-05m.htmlhttp://spaceflightnow.com/news/n0506/02phoenix/http://www.universetoday.com/am/publish/ mars_phoenix_prepares_2007.html

End Marsbugs, Volume 12, Number 19.

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