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Marsbugs: The Electronic Astrobiology Newsletter, Volume 11, Number 34, 31 August 2004




Marsbugs: The Electronic Astrobiology Newsletter

Volume 11, Number 34, 31 August 2004


Editor/Publisher: David J. Thomas, Ph.D., Science Division, Lyon College, Batesville, Arkansas 72503-2317, USA. dthomas@lyon.edu
Marsbugs is published on a weekly to monthly basis as warranted by the number of articles and announcements. Copyright of this compilation exists with the editor, except for specific articles, in which instance copyright exists with the author/authors. Opinions expressed in this newsletter are those of the authors, and are not necessarily endorsed by the editor or by Lyon College. E-mail subscriptions are free, and may be obtained by contacting the editor. Information concerning the scope of this newsletter, subscription formats and availability of back-issues is available at http://www.lyon.edu/projects/marsbugs. The editor does not condone "spamming" of subscribers. Readers would appreciate it if others would not send unsolicited e-mail using the Marsbugs mailing lists. Persons who have information that may be of interest to subscribers of Marsbugs should send that information to the editor.


Articles and News
Page 1 MARS SOCIETY CONVENTION A SMASHING SUCCESS

Mars Society release


Page 2 METEORITES SUPPLIED EARTH LIFE WITH PHOSPHORUS, SCIENTISTS SAY

By Lori Stiles


Page 4 SCIENTISTS SEEK SCENT OF LIFE IN METHANE AT MARS

By Leonard David


Page 4 BRITISH SCIENTIST ASKS NASA FOR HELPING HAND TO MARS

From Agence France-Presse and SpaceDaily


Page 4 PERIODIC DIMMING OF BRIGHT STARLIGHT REVEALS DISTANT PLANET

National Center for Atmospheric Research release


Page 5 FOURTEEN TIMES THE EARTH—ESO HARPS INSTRUMENT DISCOVERS SMALLEST EVER EXTRA-SOLAR PLANET

European Southern Observatory release


Page 7 CITIZEN OF THE SOLAR SYSTEM (INTERVIEW WITH DAVID MORRISON)

From Astrobiology Magazine


Page 8 IGNITION THRESHOLD FOR IMPACT-GENERATED FIRES

Southwestern Research Institute release


Page 9 THE PATHWAY LESS TRAVELED

By Karen Miller and Tony Phillips


Page 10 LIFE ON MARS: A DEFINITE POSSIBILITY

By Henry Bortman


Page 11 NASA SATELLITES DETECT "GLOW" OF PLANKTON IN BLACK WATERS

NASA release 2004-280


Page 12 SCIENTISTS DISCOVER FIRST OF A NEW CLASS OF EXTRASOLAR PLANETS

NASA release 2004-212



Announcements
Page 13 CALL FOR PAPERS: FALL AGU MEETING SPECIAL SESSION SH11, "THE SPACE PHYSICS OF LIFE"

From the NASA Astrobiology Institute Newsletter


Page 14 ASTROBIOLOGY SESSION TO MAKE AN “IMPACT” AT AGU

From the NASA Astrobiology Institute Newsletter


Page 14 FOURTH EUROPEAN WORKSHOP ON EXO/ASTROBIOLOGY "LIFE IN EXTREME ENVIRONMENTS" NOVEMBER 2004

From the NASA Astrobiology Institute Newsletter


Mission Reports
Page 15 CASSINI-HUYGENS UPDATES

NASA/ESA releases


Page 16 DEEP IMPACT UPDATE

From Deep News


Page 17 MARS EXPLORATION ROVERS UPDATES

NASA/JPL releases


Page 18 MARS EXPRESS UPDATES

ESA releases


Page 20 MARS GLOBAL SURVEYOR IMAGES

NASA/JPL/MSSS release


Page 20 MARS ODYSSEY BEGINS OVERTIME AFTER SUCCESSFUL MISSION

NASA/JPL release 2004-209


Page 21 MARS ODYSSEY THEMIS IMAGES

23-27 August 2004


Page 22 ROSETTA: LGA THRESHOLD TEST SUCCESSFUL (REPORT FOR 6 TO 20 AUGUST)

ESA release




MARS SOCIETY CONVENTION A SMASHING SUCCESS

Mars Society release


23 August 2004
The 7th International Mars Society convention has been a smashing success. Held at the historic Palmer House Hilton, Chicago, IL from August 19-22, the convention gathered 400 leading space scientists, engineers, government officials, entrepreneurs, activists, authors, and artists from many countries, including the USA, Canada, Mexico, Venezuela, Britain, Ireland, Spain, France, Belgium, Holland, Germany, Poland, Japan, China, India, and Australia to discuss ways and means of advancing the exploration and settlement. Over 120 papers were presented, and over $50,000 was raised to further the work of the Mars Society. The conference received prominent coverage in many important Chicago area media, including The Chicago Tribune, the Chicago Sun-Times, the Journal-Herald, NPR Radio, and Fox TV News.
Among the highlights of the convention was the opening plenary by Mars Society President Robert Zubrin, who explained how a coherent joint Moon-Mars system development could enable the exploration of both bodies at much lower cost and risk, and shorter schedule than the wasteful "first Moon, then Mars" approach being pushed on NASA by certain quarters. Zubrin's presentation was followed by Dr. Steven Squyres, the Principal Investigator of the Mars Exploration Rover mission, which has discovered conclusive evidence for existence of large standing bodies of water for long durations of Mars' early history, habitable environments in which life could have once evolved. Squyres made it clear that he believed that human exploration was a necessary follow-up to the robotic exploration of Mars. This prompted one reporter to observe, "There are all these characters who say that Mars can be explored just with robots. But the guy who is actually exploring Mars with robots says we need to send people. That says it all."
Squyres was followed by Admiral Craig Steidle, NASA Associate Administrator for Exploration Systems, who is leading the space agencies efforts to return humans to the Moon and proceed onward to Mars. Steidle explained his plan for "spiral development" of the necessary systems for human exploration, and emphasized that he hoped to work closely with the Mars Society in moving the program forward. Steidle reemphasized this latter point in a comment which appeared in the Sunday Chicago Tribune August 22, in which he said; "Societies like the Mars Society are extremely important to us. They have an innovative and thorough process. We hope to continue the journey together."
Other exciting plenary talks included Dr. Mike Lembeck, who serves as Steidle division chief for requirements development, who explained how his group is laying out the roadmap for technology development to open the solar system; Dr. Bill Clancey, the head of human centered computing at NASA Ames Research Center, who presented a talk and video showing research his group has done at the Mars Society's Mars Desert Research Station investigating techniques for combined human-robot exploration on

Mars; Dr. Stan Borowski, of the NASA Glenn Research Center, and the space agency's top expert on nuclear thermal rocket (NTR) propulsion, who explained how NTR technology could enable accelerated cost-effective exploration of the Moon, Mars, and beyond; Dr. Chris McKay, of NASA Ames Research Center, who explained the central significance of the search for life on Mars to resolving the question of the diversity and prevalence of life in the universe; Eric Anderson; President and CEO of Space Adventures Ltd., who explained how space tourism could potentially open a market that would establish the economic basis for commercially financed space settlement; Dr. Fred Pohl, a Grandmaster of science fiction (author of many award winning works, including The Space Merchants) who presented a science fiction visionary's view of "When will humankind become a



spacefaring species." Dr. Scott Horowitz, astronaut and Shuttle commander, who piloted the second Hubble repair mission, presented an astronaut's view of human Mars exploration.
A major sensation was caused at the convention by the announcement by award-winning filmmaker Sam Burbank that he would be making a theatrical motion picture based on Robert Zubrin's novel "First Landing." Listing the various Hollywood horror pictures or shoot-em-ups nominally featuring Mars, Burbank drew a sharp distinction between those efforts and the kind of movie "First Landing" will be. "There never has been a movie actually about the human exploration of Mars. This will be the first." Burbank said, "It will not be set in the glorious science fiction future, but in our own time, and it will show the mission done with all the grungy realism of the kind of space travel we can really do. It's not going to show the Mars mission as being easy. It's not going to show it as being impossible. It's going to show it as being really tough, but doable, by a group of people who have what it takes to do it."
If the heavy applause Burbank received wasn't sufficient indication of the audience's appreciation of his project, what happened next certainly was, as following his remarks, paperback copies of "First Landing" were bought up literally by the dozens by conference members mobbing the book table.
Another highlight of the conference was the showing of advance clips of James Cameron's upcoming 3-D IMAX film "Aliens of the Deep." The footage for this movie was taken by Cameron and his team operating in a flotilla of submarines operating in conjunction with mobile telerobots to explore extremophile lie forms living around hydrothermal vents 3000 ft below the Atlantic. Cameron was going to show the movie to the conference himself, but a last minute emergency called him away. However in his place he sent his co-producer and fellow underwater explorer Steve Quayle, who presented the film to the conference. The film was quite literally incredible, with the explorers discovering at every turn weird creatures that exceed the imagination of Hollywood special effects artists. The movie will appear in IMAX theaters starting in January 2005, and we give it eight hundred thumbs up. No one should miss this film. There never, ever, has been anything like it.
There is so much that could be said, and not all can. But one thing that cannot escape mention is the joy and excitement brought to the convention by the space song contest. This contest, formally known as the Second Rouget De Lisle space song competition (so named after the musical genius who wrote "La Marseillaise," and thus gave the French Revolution its rousing anthem) was conducted over the past year, during which over 100 songs celebrating human space exploration were submitted. These were downselected to 20 finalists who sang off in public competition on the evening of Friday August 20. The audience of Mars Society members voted for the top six, who then sang in final competition at the Saturday night banquet. These songs were outstanding, and it was hard to judge between them. But for the record, the winners are:

Gold Medal Category: 1st place, "Thank God Dreams Survive," by Bill, Tina, and Casey Swindell; 2nd place, "On to Mars," by Robert McNally.

Silver Medal Category: 3rd Place, "Lullaby for Mars," by S. Miria Jo; 4th Place, "When Mice Become Men," by Janetta Deavers.

Bronze Medal Category: 5th Place, "Make this World Come Alive," written by Leslie Fish, sung by Beatriz Serrato; 6th Place, "First Footprint," by Robert McNally.
All 20 of the finalists have been forwarded to Prometheus Music (producers of the highly successful "To Touch the Stars" CD which featured selections from the previous Rouget de Lisle" song contest) for possible inclusion in its next release. Songs from the first Rouget de Lisle contest have been posted and are available for downloading at the "Mars Songs" link at www.marssociety.org. By popular demand, there will be a Third Roget de Lisle competition for songs celebrating the human exploration of space next year.
Next year's Mars Society convention will be held next August at the University of Colorado in Boulder. The conference plenary hall there is known as the Glen Miller ballroom, after the famous musician and CU graduate, who was lost over the English Channel while traveling to lift the spirits of the troops trying to break out of the Normandy beachhead during June 1944. It's fitting that his ballroom should host the meeting of those seeking to break humanity out of its planetary beachhead. And this time the musicians to rouse their spirits will be there too.
For further information about the Mars society, visit our web site at www.marssociety.org.
METEORITES SUPPLIED EARTH LIFE WITH PHOSPHORUS, SCIENTISTS SAY

By Lori Stiles



University of Arizona release
24 August 2004
University of Arizona scientists have discovered that meteorites, particularly iron meteorites, may have been critical to the evolution of life on Earth. Their research shows that meteorites easily could have provided more phosphorus than naturally occurs on Earth — enough phosphorus to give rise to biomolecules which eventually assembled into living, replicating organisms.
Phosphorus is central to life. It forms the backbone of DNA and RNA because it connects these molecules' genetic bases into long chains. It is vital to metabolism because it is linked with life's fundamental fuel, adenosine triphosphate (ATP), the energy that powers growth and movement. And phosphorus is part of living architecture ­ it is in the phospholipids that make up cell walls and in the bones of vertebrates.
"In terms of mass, phosphorus is the fifth most important biologic element, after carbon, hydrogen, oxygen, and nitrogen," said Matthew A. Pasek, a doctoral candidate in UA's planetary sciences department and Lunar and Planetary Laboratory. But where terrestrial life got its phosphorus has been a mystery, he added.
Phosphorus is much rarer in nature than are hydrogen, oxygen, carbon, and nitrogen. Pasek cites recent studies that show there's approximately one phosphorus atom for every 2.8 million hydrogen atoms in the cosmos, every 49 million hydrogen atoms in the oceans, and every 203 hydrogen atoms in bacteria. Similarly, there's a single phosphorus atom for every 1,400 oxygen atoms in the cosmos, every 25 million oxygen atoms in the oceans, and 72 oxygen atoms in bacteria. The numbers for carbon atoms and nitrogen atoms, respectively, per single phosphorus atom are 680 and 230 in the cosmos, 974 and 633 in the oceans, and 116 and 15 in bacteria.



Artist's illustration of early Earth, 4.5 billion years ago, about a year after a Mars-sized object hit Earth and formed the Earth-Moon system. The still molten moon with an impact in progress (upper left) is viewed from Earth's volcanic surface. Meteorites and comets—like the comet visible in the sky—delivered materials needed for life on Earth. Rings remaining from the collision and other debris, including moonlets not yet swept up by the moon, are visible. An Orion-like nebula appears at upper right. (Painting copyrighted by artist James V. Scotti, UA Lunar & Planetary Lab).
"Because phosphorus is much rarer in the environment than in life, understanding the behavior of phosphorus on the early Earth gives clues to life's origin," Pasek said.
The most common terrestrial form of the element is a mineral called apatite. When mixed with water, apatite releases only very small amounts of phosphate. Scientists have tried heating apatite to high temperatures, combining it with various strange, super-energetic compounds, even experimenting with phosphorous compounds unknown on Earth. This research hasn't explained where life's phosphorus comes from, Pasek noted.


Pasek with lab equipment. The tube contains a meteorite sample dissolved in fresh water.
Pasek began working with Dante Lauretta, UA assistant professor of planetary sciences, on the idea that meteorites are the source of living Earth's phosphorus. The work was inspired by Lauretta's earlier experiments that showed that phosphorus became concentrated at metal surfaces that corroded in the early solar system.
"This natural mechanism of phosphorus concentration in the presence of a known [in]organic catalyst (such as iron-based metal) made me think that aqueous corrosion of meteoritic minerals could lead to the formation of important phosphorus-bearing biomolecules," Lauretta said.
"Meteorites have several different minerals that contain phosphorus," Pasek said. "The most important one, which we've worked with most recently, is iron-nickel phosphide, known as schreibersite."



Image of schreibersite grain present in a thin-section of the enstatite meteorite, KLE 98300. This image was taken using reflected light and is 1 mm across. Image credit: Virginia Smith, UA Lunar & Planetary Laboratory.
Schreibersite is a metallic compound that is extremely rare on Earth. But it is ubiquitous in meteorites, especially iron meteorites, which are peppered with schreibersite grains or slivered with pinkish-colored schreibersite veins.
Last April, Pasek, UA undergraduate Virginia Smith, and Lauretta mixed schriebersite with room-temperature, fresh, de-ionized water. They then analyzed the liquid mixture using NMR, nuclear magnetic resonance.
"We saw a whole slew of different phosphorus compounds being formed," Pasek said. "One of the most interesting ones we found was P2O7 (two phosphorus atoms with seven oxygen atoms), one of the more biochemically useful forms of phosphate, similar to what's found in ATP."
Previous experiments have formed P207, but at high temperature or under other extreme conditions, not by simply dissolving a mineral in room-temperature water, Pasek said.
"This allows us to somewhat constrain where the origins of life may have occurred," he said. "If you are going to have phosphate-based life, it likely would have had to occur near a freshwater region where a meteorite had recently fallen. We can go so far, maybe, as to say it was an iron meteorite. Iron meteorites have from about 10 to 100 times as much schreibersite as do other meteorites.
"I think meteorites were critical for the evolution of life because of some of the minerals, especially the P207 compound, which is used in ATP, in photosynthesis, in forming new phosphate bonds with organics (carbon-containing compounds), and in a variety of other biochemical processes," Pasek said.
"I think one of the most exciting aspects of this discovery is the fact that iron meteorites form by the process of planetesimal differentiation," Lauretta said. That is, the building-blocks of planets, called planestesmals, form both a metallic core and a silicate mantle. Iron meteorites represent the metallic core, and other types of meteorites, called achondrites, represent the mantle.
"No one ever realized that such a critical stage in planetary evolution could be coupled to the origin of life," he added. "This result constrains where, in our solar system and others, life could originate. It requires an asteroid belt where planetesimals can grow to a critical size ­ around 500 kilometers in diameter ­ and a mechanism to disrupt these bodies and deliver them to the inner solar system."
Jupiter drives the delivery of planetesimals to our inner solar system, Lauretta said, thereby limiting the chances that outer solar system planets and moons will be supplied with the reactive forms of phosphorus used by biomolecules essential to terrestrial life. Solar systems that lack a Jupiter-sized object that can perturb mineral-rich asteroids inward toward terrestrial planets also have dim prospects for developing life, Lauretta added.
This research was presented August 24th at the session "Astrobiology and the Origins of Life" of the 228th American Chemical Society national meeting in Philadelphia. The work is funded by the NASA program, Astrobiology: Exobiology and Evolutionary Biology.
[http://uanews.org/silk/downloads/schreibersite.jpg]

Image of schreibersite grain present in a thin-section of the enstatite meteorite, KLE 98300. This image was taken using reflected light and is 1 mm across. Image credit: Virginia Smith, UA Lunar & Planetary Laboratory.
Contacts:

Lori Stiles

UA News Services

Phone: 520-621-1877


Matthew A. Pasek

Phone: 520-621-1594

E-mail: mpasek@lpl.arizona.edu
Dante Lauretta

Phone: 520-626-1138

E-mail: lauretta@lpl.arizona.edu
Read the original news release at http://uanews.org/cgi-bin/WebObjects/UANews.woa/8/wa/SciDetails?ArticleID=9567.
Additional articles on this subject are available at:

http://www.astrobio.net/news/article1153.html

http://www.spacedaily.com/news/early-earth-04l.html

http://www.universetoday.com/am/publish/meteorites_provided_phosphorus.html



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