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Marsbugs: The Electronic Astrobiology Newsletter, Volume 11, Number 15, 6 April 2004
Marsbugs: The Electronic Astrobiology Newsletter
Volume 11, Number 15, 6 April 2004
Editor/Publisher: David J. Thomas, Ph.D., Science Division, Lyon College, Batesville, Arkansas 72503-2317, USA.
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 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.
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Marsbugs: The Electronic Astrobiology Newsletter, Volume 11, Number 15, 6 April 2004
Articles and News
Page 1HUNT FOR EXTRASOLAR EARTH-LIKE PLANETS INTENSIFIES
Royal Astronomical Society press notice PN04-14
Page 2MOON-TO-MARS FEASIBLE, EXPERTS SAY, BUT POLITICS, LACK OF INDUSTRY COOPERATION COULD JEOPARDIZE VISION
By Leonard David
Page 2CAN INTELLIGENT LIFE THRIVE IN CLOSE QUARTERS? AN INTERVIEW WITH CHRISTOPHER CHYBA
By Henry Bortman
Page 3LIFE BENEATH THE ICE IN THE OUTER SOLAR SYSTEM?
Royal Astronomical Society press notice PN04-10
Page 4TITAN'S LAPPING OIL WAVES
Based on a Royal Astronomical Society report
Page 5HUMAN EXPLORATION OF THE MOON AND MARS
Royal Astronomical Society press notice PN04-09
Page 5METHANE DETECTION POINTS TO LIFE ON MARS
By Robert Zubrin
Page 6MOLECULAR MIDWIVES HOLD CLUES TO THE ORIGIN OF LIFE
From SpaceDaily
Page 7PLANETARY SYSTEMS WITH HABITABLE EARTHS?
Royal Astronomical Society press notice PN04-13
Page 8SPACE DEFINES MARS SAMPLE RETURN MISSION
EADS Astrium press release
Page 8CHEAP COMMUNICATION SCHEMES FOR ET
By Seth Shostak
Page 8ASHES OF THE PHOENIX
By Peter Backus
Page 9EUROPA: LIVING WORLD OR FROZEN WASTELAND? AN INTERVIEW WITH CHRISTOPHER CHYBA
By Henry Bortman
Announcements
Page 10NEW ADDITIONS TO THE ASTROBIOLOGY INDEX
By David J. Thomas
Mission Reports
Page 11CASSINI SIGNIFICANT EVENTS
NASA/JPL release
Page 12MARS EXPLORATION ROVERS STATUS REPORTS
NASA/JPL releases
Page 14MARS EXPRESS: COMMISSIONING ALMOST COMPLETE
ESA release
Page 14MARS GLOBAL SURVEYOR IMAGES
NASA/JPL/MSSS release
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Marsbugs: The Electronic Astrobiology Newsletter, Volume 11, Number 15, 6 April 2004
1
Marsbugs: The Electronic Astrobiology Newsletter, Volume 11, Number 15, 6 April 2004
HUNT FOR EXTRASOLAR EARTH-LIKE PLANETS INTENSIFIES
Royal Astronomical Society press notice PN04-14
23 March 2004
An international group of astronomers led by Dr. Jean-Philippe Beaulieu (Institut d'Astrophysique de Paris) and Dr. Martin Dominik (University of St. Andrews) are about to continue their hunt for extrasolar planets with an enhanced world-wide telescope network in May this year. They are hoping to secure the firm evidence for the existence of Earth-mass planets orbiting stars other than the Sun, which has so far eluded astronomers. Dr. Dominik will describe the project, known as PLANET (Probing Lensing Anomalies NETwork), at the Royal Astronomical Society National Astronomy Meeting at the Open University on Thursday 1 April.
Recent scientific research shows that the existence of life on other worlds is a realistic scenario. By measuring the periodic variation of the radial velocity of stars induced by an orbiting planet, astronomers have so far detected over 100 planets but all of them are large, similar to Jupiter and Saturn in our solar system, and environmental conditions suitable for life do not exist on such gas giant planets.
The only technique currently capable of detecting planets similar to Earth makes use of the phenomenon called "galactic microlensing". In a microlensing event, a star temporarily appears brighter than it really is because another astronomical body is passing between it and observers on Earth; the gravitational field of the intervening object affects the starlight in a way similar to a lens.
If the intervening object is a star, it causes a characteristic signal that lasts about a month. Any planets orbiting this star can produce significant deviations in the signal, lasting days for giant planets down to hours for Earth-mass planets. The probability of this happening is between 1.5% and 20% depending on the mass of the planet.
The PLANET campaign performs nearly-continuous round-the-clock high-precision monitoring of ongoing microlensing events, sampling the lightcurve at intervals that may be as little as few minutes with a world-wide network of telescopes. The backbone of the network is formed by the Danish 1.54-m telescope at the European Southern Observatory at La Silla (Chile), the Canopus Observatory 1.0-m telescope (Tasmania, Australia), the Perth 0.6-m telescope (Western Australia), and the Boyden 1.5-m telescope (South Africa), which is supplemented by some other telescopes. PLANET will share information and some resources with the microlensing campaign performed with RoboNet, a UK robotic telescope network comprised of the Liverpool 2.0-m (Canary Islands, Spain) and the two Faulkes 2.0-m telescopes (Hawaii and Australia).
From the 500-700 microlensing events announced annually by the survey campaigns OGLE and MOA that monitor tens of millions of stars on a daily basis, PLANET focuses on up to 75 events that are selected as most suitable candidates for the detection of planets around the intervening lens star. "If 20% of these stars are surrounded by planets, 10-15 giant planets and 1 or 2 terrestrial planets are expected to reveal their existence over three years of operation", Dr. Dominik said.
While PLANET might detect a second Earth, its typical expected distance would be 20,000 light years—much too far to think of establishing any contact!
Contacts:
Dr. Martin Dominik
University of St. Andrews
School of Physics & Astronomy
North Haugh, St. Andrews
KY16 9SS United Kingdom
Phone: (+44)-(0)1334-463066
Fax: (+44)-(0)1334-463104
E-mail:
Dr. Jean-Philippe Beaulieu
Institut d'Astrophysique de Paris
98bis Boulevard d'Arago 75014 Paris France
Phone: +33-1-44-328119
Fax: +33-1-44-328001
E-mail:
Read the original news release at
Additional articles on this subject are available at:
MOON-TO-MARS FEASIBLE, EXPERTS SAY, BUT POLITICS, LACK OF INDUSTRY COOPERATION COULD JEOPARDIZE VISION
By Leonard David
From Space.com
30 March 2004
President George W. Bush’s vision to send robotic and human explorers back to the Moon, on to Mars and beyond can be made affordable and sustainable. But turning rhetoric into reality will require drawing upon the talents of civil and military abilities, as well as industrial prowess, policy and space technologists participating in the 20th annual meeting of the National Space Symposium said Tuesday.
Participating in the panel, "The New NASA Vision—How We Got Here. What It Means," Bretton Alexander, Senior Policy Analyst at the White House Office of Science and Technology Policy, outlined President Bush’s January 14th marching orders for NASA. Alexander said the tragic loss of the shuttle Columbia early last year created a crisis in the civilian space sector, compounded by the lack of a compelling vision for the nation’s human space flight program. There has been a 30-year national debate as to the nation’s space goals, he said, which President Bush has ended by setting the country on a bold course for the 21st century.
James Kennedy, Director of NASA’s John F. Kennedy Space Center in Florida urged that the Bush plan for space must be more than a partisan, one-President commitment.
"I personally think it’s time, after Congress has spoken on this subject... it’ll be time for this to be no longer the President’s vision. This should be de-politicized. It should be our national vision of space exploration," Kennedy said. "I hope that we adopt that as our own personal vision."
Read the full article at
CAN INTELLIGENT LIFE THRIVE IN CLOSE QUARTERS? AN INTERVIEW WITH CHRISTOPHER CHYBA
By Henry Bortman
From Astrobiology Magazine
31 March 2004
Christopher Chyba is the principal investigator for the SETI Institute lead team of the NASA Astrobiology Institute. Chyba formerly headed the SETI Institute's Center for the Study of Life in the Universe. His NAI team is pursuing a wide range of research activities, looking at both life's beginnings on Earth and the possibility of life on other worlds. One of his team's research projects will explore a question critical to the search for extraterrestrial intelligence. Can planets orbiting red dwarf M-type stars support life—perhaps even intelligent life? Astrobiology Magazine's managing editor Henry Bortman recently spoke with Chyba about Tarter's, Mancinelli's, and Backus's research.
SETI's Jill Tarter (left), Peter Backus (center), and Rocco Mancinelli (right). Image credit: SETI Institute.
Astrobiology Magazine: Jill Tarter and Peter Backus, and microbiologist Rocco Mancinelli, all of whom are with the SETI Institute, are involved in the search for extraterrestrial intelligence. Their contribution to your NAI team's research will be to consider the habitability of M-class red dwarf stars, their potential as SETI targets.
At a forum last winter, Frank Drake explained his famous Drake Equation, which calculates the likelihood that there are other intelligent species in our galaxy. One of the equation's factors, R*, has to do with the rate at which the galaxy produces stars that provide environments capable of supporting intelligent life. He said that a major question in determining this factor had to do with the habitability of M-class stars. Of the 20 or so stars produced in the galaxy each year, 15 of them are dim M dwarfs. And so, if it turns out that planets around M dwarfs could support intelligent life, there would be many more stars on the SETI target list than if M dwarfs were excluded. Is that the question that Jill, Rocco and Peter are hoping to answer?
Christopher Chyba: You're right on target. We're going to have a series of workshops that involve project co-investigators and other people who are experts in stellar evolution—and also biologists, microbiologists, and it's likely we'll bring others in—to look at this question of the habitability of worlds around M stars.
There are two reasons why that question is tough. One's mostly a red herring, and the other is more significant. For a planet to be in the so-called habitable zone of an M star, it has to be close enough to have liquid water. For a red dwarf, that means it has to be real close, because the star is dim. But that also means that it's going to be close enough that on a geologically short time span it's going to be spin-locked, with the same side of the planet always facing the star, the way the moon is with the Earth.
There was concern for a while—this is featured in Rare Earth—that that would mean that all of the planet's atmosphere would freeze out on its dark side, and that would be that. But, in fact, if you do the greenhouse simulations—Joshi et al. published these results in 1997— for those kinds of worlds, you find that you need only around a tenth of a bar of carbon dioxide to give you a thick enough atmosphere, enough greenhouse effect, that youredistribute the heat so that your atmosphere doesn't freeze out. That's a lot more carbon dioxide than we have on Earth, but well within the range ofwhat's plausible.
If you get up into the range of a bar or so of carbon dioxide, not only does your atmosphere not freeze out, but you stay warm on both sides of the planet, so you have liquidwater potentially all over the planet. You have no guarantees that a planet around an M dwarf will have that much carbon dioxide. But you don't have any guarantee of havingthe atmosphere you want on a planet around a G-class (sun-like) star, either. So I don't think that's a decisive problem, although we will certainly revisit that.
The other issue, though, has to do with flaring from those stars. Its radiation environment might be too harsh for life on planets around M stars, although papers published asearly as 1991 called this into question. And that's something that we need a much better understanding of, astrophysically and atmospherically. We also want to have biologistsin the picture so that we can get a better handle on just how challenging the radiation and ultraviolet environments would be either for microscopic life or for more sophisticatedforms of life. And that will ultimately lead to an operational decision about whether or not we expand the list of target stars for our SETI search to include M stars. Remember,as Frank said, these are 75 percent of the nearby stars. So answering this question will have a huge impact on our search strategy.
Left: Frank Drake, whose famous Drake Equation calculates the likelihood that there are other intelligent species in our galaxy. Right: Christopher Chyba, principal investigator for NASA Astrobiology Institute's SETI lead team. Image credit: SETI Institute.
AM: I'm surprised that NASA is funding a research project whose focus is the search for extraterrestrial intelligence. I was under the impressionthat NASA was forbidden by Congress from funding SETI.
CC: No, that's no longer the case. Let me clarify, and then explain what's changed, because this is something that has often caused confusion. There was never any prohibition against NASA funding research projects out of the SETI Institute. What the prohibition was understood to be—really, misunderstood to be—was a prohibition against funding SETI science, whether it was the SETI Institute, or the Harvard SETI project, orthe Berkeley SETI project, or any other SETI project. The interpretation was that they were not permitted to fund that entire area of science.
What was really the case was that Congress zeroed SETI research out of the NASA budget in '93—but that was a one-time elimination from thebudget. There wasn't any language saying, "You shall never fund SETI research ever again." But it was interpreted that way, and I understandthat. A government agency thinks it gets a directive from Congress and it wants to be faithful to that.
What's changed is that the sense of Congress is different now. And you can see that back to at least 2001, when the Aeronautics and SpaceSubcommittee of the House Science Committee held a hearing on life in the universe, and they had four or five people testifying, including myself. Itestified mostly about astrobiology and how SETI is a natural component of the continuum of questions asked in astrobiology. And there was a clearsense of the committee at that time, at the hearing, that SETI was part of astrobiology. In fact, this led to a statement that NASA would consider SETIscience projects equally under peer review with other projects that fit within astrobiology. That is to say, NASA could make these decisions on thebasis of peer review, rather than on the basis of some extra-scientific reason. That was, after all, reflected in the new Astrobiology Roadmap, which for the first time includes SETI as a component of astrobiology. And the fundingfor a SETI project within this proposal is just a kind of natural outcome of that process.
But you're right, in the sense that that's a shift in at least perception in the last few years. And I think a few things have happened. One is that, while it'sstill entirely possible that there's no life anywhere else in the known universe other than Earth—we don't have definite evidence that there's life anywhereelse—there has been a whole series of discoveries that make it seem more plausible that there's extraterrestrial life. So I think that's the intellectualcontext. And there's a lot of enthusiasm in Congress now.
The other thing to mention is that there is a standing committee of the National Academy of Sciences National Research Council, the Committee onthe Origin and Evolution of Life, which was asked by Congress to do a report on astrobiology, and in particular to assess the role of SETI in astrobiology. And thatcommittee's report is effusive in its praise for SETI and, to be frank, the SETI Institute, so I think that played a role, too, because that represented outside support. So I think a lot of things came together in the space of the last few years.
Read the original article at
LIFE BENEATH THE ICE IN THE OUTER SOLAR SYSTEM?
Royal Astronomical Society press notice PN04-10
31 March 2004
At present, we know of no worlds beyond our Earth where life exists. However, primitive organisms on our planet have evolved and adapted over billions of years, colonizing the most inhospitable places. Since life seems to gain a foothold in the most hostile environments, it seems distinctly possible that living organisms could exist in ice-covered oceans on worlds far from the Sun, according to Dr. David Rothery (Open University), who will be speaking today at the RAS National Astronomy Meeting in Milton Keynes.
This image of Jupiter's icy satellite Europa shows surface features such as domes and ridges, as well as a region of disrupted terrain including crustal plates which are thought to have broken apart and "rafted" into new positions. The image covers an area of Europa's surface about 250 by 200 kilometer (km) and is centered at 10 degrees latitude, 271 degrees longitude. The color information allows the surface to be divided into three distinct spectral units. The bright white areas are ejecta rays from the relatively young crater Pwyll, which is located about 1000 km to the south (bottom) of this image. These patchy deposits appear to be superposed on other areas of the surface, and thus are thought to be the youngest features present. Also visible are reddish areas which correspond to locations where non-ice components are present. This coloring can be seen along the ridges, in the region of disrupted terrain in the center of the image, and near the dome-like features where the surface may have been thermally altered. Thus, areas associated with internal geologic activity appear reddish. The third distinct color unit is bright blue, and corresponds to the relatively old icy plains. Image credit: NASA/University of Arizona.