Ladies and Gentleman, boys and girls, earthlings and aliens, I just came back from AbSciCon, the astrobiology science conference in Santa Clara, and my head is so full of astrobiology that I think it might explode. Three days, six hundred and fifty papers, two thousand authors total, twenty-eight countries represented. I gave an education talk on my Second Life work, but the breadth of research results made it an incredible meeting. I can barely give you a sense of what was involved, but I’ll select three papers to talk about in particular.

The keynote address at the beginning of the first day was a wonderful overview of the cosmic context of life given by Lord Martin Rees. Yes, if you weren’t aware of it, over in Britain there’s a scientist who’s so famous he not only was knighted and became Sir Martin Rees but he is now in the House of Lords. Even Isaac Newton didn’t go beyond a knighthood. Martin Rees is also the Astronomer Royal, and he made a joke about the fact that his primary duty there involves casting the queen’s horoscope. He’s the president of the Royal Society, and he holds Newton’s Chair of Astronomy hundreds of years later. He also happens to be a really nice guy.

Rees a brilliant and preeminent cosmologist, and he talked about the setting for life in the universe on the largest scales. He reminded the audience that we expect the universe to be fecund and have material that can form life and biology because of the way carbon has been created and flung out from stars through cosmic time. He also—unusually for most scientists—was strongly supportive of SETI, pointing out that it’s an important philosophical experiment to actively look for extraterrestrial intelligence, though he noted that we’re only likely to detect a small fraction of all the possible brains out there. He made several references to science fiction and in one aside said that he preferred first-rate science fiction to second-rate science any day, but mostly he was talking about cosmology.

He homed in on the six numbers that describe the universe on the largest scales and the fact that some of those numbers are poised at values that permit the existence of life. These cosmic coincidences have begged an explanation by cosmologists, and the most popular one involves the fact that we live in a multiverse, a “small” pocket of space-time that could be part of a much larger construct. Most of these universes in the multiverse are sterile because their physical properties would not permit stable atoms or long-lived stars or biology of any kind, but ours of course is not. He also gave a sense of how vast the totality of the universe could be, so vast that it’s kaleidoscopic in proportion and so vast that all the possible probability outcomes may occur somewhere in space and time. It was a head spinning talk, and it really set the scene for all the work that would follow.

The second talk I want to highlight was given by Richard Muller at the University of California, Berkeley. He gave a wonderful overview of a new signal seen in the extinction of marine creatures on Earth in the past half billion years, that shows a strong periodicity. We know there have been mass extinctions in the history of life on Earth, but it’s mostly been thought that they were random, probably caused by cosmic impacts from space or some sort of climate catastrophe. But Muller has used an enormous compendium by the late Jack Sepkoski of fossil marine data to do a new analysis, and he’s found a very strong evidence for a sixty-two million year cycle in the death of species.

His new analysis involves a lot of new data that he was willing to share with anyone in the audience, making available his Excel spreadsheet. It involves tens of thousands of marine species. The sixty-two million year cycle only leaps out when a new age calibration is used. It turns out that the ages for fossil dating over the past half billion years had errors of up to ten or twenty million years, and that was enough to smear out this signal. But with the new age calibration it was obvious in all his graphs. It’s seen separately in trilobites, bivalves, porifera, and brachiopods, less strongly in gastropods, cephlopods, and fish. He also sees weaker evidence for a hundred and forty million year cycle. The existence of two periodicities in the extinction of marine creatures over half a billion years begs for an astronomical explanation because something that’s periodic is probably coupled to orbits or gravity in some way.

The potential explanation of these two cycles was provided by a pair of talks that followed by Mikhail Medvedev and Adrian Melott. The hundred and forty million year cycle, for which the evidence is still fairly weak, is probably caused by the periodic passage of the Sun and the Solar System through the spiral arms of the Milky Way galaxy. The sixty-two million year cycle exactly matches the period of the Sun’s motion up and down in the plane of the Milky Way galaxy.

Imagine the Milky Way and its disk as an old style phonograph record, a 33 record, warped by heat so it is corrugated and the Sun travels up and down and in and out of the plane of the galaxy as it goes round, with a two hundred and fifty million year orbit and a sixty-two million year cycle for the up and down motion. At its maximum excursion from the plane of the Milky Way, the Earth and the Solar System sees an increased flux of cosmic rays, and this increased flux of cosmic rays causes mutation of DNA, climate change, and the combination is a one-two punch that kills species. So we have a very neat explanation for the periodicity of extinctions. It’s caused by our large-scale astrophysical environment, and we might wonder if other life bearing planets in the Milky Way galaxy are subject to similar periodicities.

The last talk I want to mention was by Denise Herzing from the Wild Dolphin Project in Florida. The Wild Dolphin Project is just what you might imagine. This woman has an incredible job. For nearly twenty-five years she’s spent five months of the year out in the Bahamas tracking, playing, and working with Atlantic spotted dolphins. She’s a behaviorist, and they try to be as least intrusive as possible in the dolphin culture. For that span of time they’ve studied two hundred individuals over three generations, and they know many of these individuals by sight and behavior after that length of time.

Remember, these are wild dolphins. This is not a controlled situation, and yet they’ve managed to record sounds to correlate behavior and vocalization and learned an enormous amount about dolphins that wasn’t known before. As Carl Sagan noted some years ago, we’ve managed to train dolphins to speak about two hundred words of English by tapping out symbols on a keyboard but we still speak exactly zero words of dolphin. So who’s smarter? Denise’s presentation made it clear that these incredible creatures display fantastically complex behavior and socializations.

She and her colleagues were able to train the dolphins to use a portable underwater keyboard to tap out symbols and essentially communicate with the humans. The dolphins that participated were mostly the young females. It seems that the young males were off fighting, as in other species, and what she summarized was a rich tapestry of subtle behavior, plus evidence of substantial intelligence and problem-solving abilities and of distinct personalities amongst the dolphins. That’s perhaps a good way to leave the idea of astrobiology from this major recent gathering of astrobiologists—while we look for intelligent, interesting creatures out in space, we should remember that we share a planet with extraordinary creatures that we don’t yet fully understand.

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Early in the year there was official notification of the threat to the biosphere of the planet Earth when the journal The Bulletin of the Atomic Scientists moved their Doomsday Clock, the one that counts down to midnight and annihilation, to five minutes to midnight. This indicates we are threatening our biosphere at a level that could extinguish life on this planet. So even though we have the only living planet, it may not be a living planet forever, that was a sobering way to start the year.

The second story came in March. The world’s oldest sedimentary rocks showed that carbon dioxide released by volcanoes saved the Earth from a snowball episode seven hundred million years ago, one that nearly annihilated life. A third story was the detection of water in the atmosphere of an extrasolar planet, the first time this vital substance for biology had ever been detected at any of the exoplanets. It was very exciting, but this planet is a giant hot Jupiter and definitely not habitable by life as we know it. That caveat is very important; astrobiology is often hampered by not knowing how strange life elsewhere might be.

The fourth story was for me the top story of the year: the discovery of the most Earth-like planet yet, sitting in the habitable zone of a red dwarf dozens of light years away, a planet only five times the mass of the Earth. This exoplanet is a place where liquid water could exist and, who knows, maybe life. That was late April. In a splashy announcement in the middle of the year, in one press release, twenty-eight new exoplanets were released, thus bringing the total to over two hundred and fifty, an exciting sign of how far the harvesting of exoplanets has progressed in the last decade.

The sixth story was the release of a report from the National Research Council urging that scientists search for life as we “don’t know it.” The report said that if they presume too absolutely that there’s only one kind of biology, scientists might completely miss the discovering weird forms of life. Most of the life out there in the universe might not be based on the template of our biology. The seventh story, which is close to my heart as I work at the University of Arizona, was the launch of the Phoenix probe for the Martian pole. It’s due to arrive in May this year, and you’re sure to hear much more about that in upcoming months.

The eighth story was of DNA being brought to life from eight million years ago, but the related discovery that DNA degrades by about fifty percent every million years probably limits the amount by which life could survive in space and travel between stars. The ninth story was the announcement that the science fiction idea teleportation is actually possible and is not precluded by the laws of physics. The tenth story was the discovery of five planets around a star, one of which was in the habitable zone, but was fifty-five times the mass of the Earth. This discovery of a complex system of planets shows that the discovery of planets has moved to a new phase, not just one planet per star but entire systems of planets around stars.

To give another perspective, I crosschecked these ten stories with the Astrobiology Magazine released online by NASA. We had three stories in common: the flight of Phoenix, the discovery of the most Earth-like planet, and the discovery that DNA degrades fifty percent every million years.

Astrobiology Magazine also highlighted the COROT telescope being launched by the European Space Agency, and a robot that went deep into a sinkhole to pioneer technology we’ll use to explore Europa we hope in upcoming decades. They also looked at a story that uncovered the inventory of frozen water at the south pole of Mars, which gives us a sense of how that planet might have supported life in the past. A weird story was the discovery that four hundred and twenty million years ago fungi stood as tall as trees, reaching twenty feet in height. I’m not sure what that tells us about life in the universe, but it’s a pretty scary thought. Another story that I didn’t have in my list was evidence against the panspermia hypothesis, the idea that life could travel from planet to planet in meteorites. The last two stories were the discovery of the parent object whose breakup led to the impact that killed the dinosaurs and many other species sixty-five million years ago, and the launch of the Dawn mission to study Vesta and the planet Ceres in the asteroid belt.

Those are the top stories of the last year, and it would be nice to report that we finally discover life elsewhere in the 2008. With the Phoenix mission landing on Mars, and new SETI telescopes listening for intelligent radio signals from distant planets, it’s just possible. We’ll keep our fingers crossed and wait.

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The season of goodwill does sometimes end with a hangover, if not due to alcohol then of course to the bills that come due. After weeks when we look forward to opening packages for the cards and presents they contain, we dread that one credit card statement that arrives sometime in January. So to echo that discontent, we’ll start 2008 by looking at how astrobiology is paid for. Where do the budgets for astrobiology come from? This exciting research is severely challenged by current constraints on the federal budget.

First, the big picture. Science in the United States is funded by four agencies: the National Science Foundation, the National Institutes of Health, NASA, and the Department of Energy. NSF could fund astrobiology, but for historical reasons it doesn’t. So virtually the entire federal funding of this subject comes from NASA. NASA has a sixteen billion dollar budget. One-third of that is for science. The rest is for the shuttle program, the International Space Station, and ongoing research on propulsion technologies. Of the one-third science budget, which amounts to about five billion dollars, less than two percent goes to astrobiology.

NASA’s been in tough times the last few years. It had deep cuts to its research budget of several hundred million dollars. That’s a fifteen percent drop in what’s called the Research and Analysis or R and A budgets. Astrobiology, which is a new discipline, took an even worse cut, fifty percent, and making matters worse, NASA made the cuts retroactive so scientists who thought they had funding lined up for the year were suddenly scrambling for new grant dollars. This is a part of the science game that most people don’t realize. I’m lucky. I have a tenured job as a faculty member and teacher at a big university. I can’t be fired, except for gross dereliction of duty or malfeasance, neither of which I plan any time soon. I only have to raise the three months of my summer salary with grants. There are many people on what’s called soft money who go from one year to the next, having to perhaps support a family, paying their entire salary with evanescent budgets of NASA and the NSF.

Last year, NASA appointed a new Associate Administrator, Alan Stern, who took office pledging to reinvest in Research and Analysis as one of the main thrusts of his strategy for getting the most out of the agency’s flat budget. He brought along two deputies, one of whom, Yvonne Pendleton, said, “R and A is only a tiny part of the overall science budget, but when you cut it you feel the effect very quickly. The people who live off this money have very little else to fall back on.” When R and A spending is cut, it affects not only the scientist who sent in the proposal but also the graduate students and post docs that would have been fed using the grant. Stern has pledged that while he’s at the helm there will be no cuts from Research and Analysis, and that’s good news for every researcher in astronomy.

In the mean time, it’s a tough game. Only one in four NASA proposals is funded. NASA is also experimenting with what Pendleton calls demand-driven balancing to ensure that all scientists, regardless of their discipline, have a roughly one in four chance of winning a grant. As the situation now stands, some of NASA’s programs fund nearly every proposal they receive while others can only afford to fund about one in ten. By moving money around, the Science Mission Directorate hopes to give every scientist an equal chance of winning a grant while at the same time ensuring that the hottest disciplines get their fair share of the available pie.

This change will definitely help astrobiology. Astrobiology is popular enough that the oversubscription of money is often worse than four to one, and so the success rate is under twenty-five percent. So things could be looking up for astrobiology. Stern has promised to rescind the fifty percent cuts to only twenty percent. But a cut is a cut, and it’s hard to do the research with less money.

While we’re looking at the NASA budget and how it affects astrobiology, we can recall that the grants program is only one part of the pie. We fall back here on the Willie Sutton principle. Willie Sutton, you may recall, was a famous bank robber from the 1970s who told the judge that he robbed banks because that’s where the money is. Well on the Willie Sutton principle, if you want to balance the NASA budget you don’t look to the grants program, which is only a few hundred million dollars, but to the big missions which are several billion dollars of NASA’s budget or ten times bigger. Unfortunately for astrobiology, some of its missions have been the villains in mismanaging or underestimating their costs.

Back to Alan Stern, who must be known in some circles as the grim reaper dude. Stern’s first target for cost overruns was the Kepler mission, a mission started in 2001 to launch a planet-hunting telescope that hopes to find Earth clones. Because of management problems and technical difficulties, the price tag went up, and the launch date slipped well beyond the original 2006 target. NASA steeled itself for a twenty percent cost overrun that raised the price to five hundred and fifty million dollars and accepted a 2008 launching date, but then the Kepler team came to Stern last spring and asked for an additional forty million dollars. He said no. In fact, he said no four times. To give teeth to the directive for fiscal responsibility, NASA threatened to open the project to new bids so other researchers could take over the equipment that had already been built. Well, that concentrated minds wonderfully, and Kepler team came up with a solution. The duration of the four-year mission was cut by six months, and pre-flight testing was scaled back. This compromised the mission but does let it go forward.

Another mission that had cost overruns was an astrobiology flagship mission, the Mars Science Laboratory. This has a price tag of 1.7 billion dollars, and its goal is to launch a nuclear powered, wheeled, robotic laboratory to Mars in late 2009, a craft that will be three times larger than the Spirit and Opportunity rovers that are now operating there. Last summer, a review revealed seventy-five million dollars in cost overruns, so Stern’s office scaled back some of its capabilities, eliminating a camera that would have taken pictures of its descent and stopping work on a laser chemistry instrument called ChemCam, developed by researchers in the United States and France, that was designed to burn off surface coatings of materials to determine their composition.

This was unpopular, stirring a real uproar among scientists. The Planetary Society space advocacy group mounted a public campaign against it and also called for a congressional review of the decision. Then, in November, Stern announced that ChemCam and the descent imager were back in the mission. The designer had offered to finish the instrument at its own expense, and the ChemCam team got more money from Los Alamos Lab, its main sponsor, and the French partners. These hardnosed tactics by NASA’s associate administrator are hoping to keep a lid on the ever-escalating cost of missions and thereby feed more money into the more modest grants program that does most of NASA’s science.

However, there is an eight-hundred-pound gorilla in the room as far as budgets are concerned, a mission I haven’t mentioned yet: the James Webb Space Telescope. This telescope is Hubble’s successor. Originally pegged at five hundred million dollars, the budget over the years has ballooned to over four billion dollars, and it won’t even be launched for six or seven years. It will be impossible for NASA to do all the science it wants to do while the budget of this one behemoth of a mission is growing in an uncontrolled way. Astrobiology will be hurt and many other types of science too. Sometimes you don’t really want to see how sausages are made, but this week I hope I’ve given you a little insight in how the sausages in of science of astrobiology depend on what goes on deep within NASA.

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This week a panel of senior scientists convened by the country’s leading science advisory group says the hunt for extraterrestrial life should be greatly expanded to include what they call weird life, organisms that lack DNA or other molecules found in life as we know it. The scientists conclude in their report that their investigation makes it likely that life is possible in forms different from those on Earth.

Experts have hailed this report as an important rethinking on the search for life. NASA’s lead scientist for the Mars Exploration Program, Mike Meyer, says, “It’s going to help us a lot to make sure we’re going exploring with our eyes wide open.” Starfish, sequoia, salamanders, and the rest of the Earth’s residents may seem diverse, but they’re surprisingly similar at the molecular scale. All species that scientists have studied need liquid water to survive, for example, and they all rely on DNA to carry genetic information. And they all use that information to build proteins from the same set of building blocks, twenty different amino acids.

NASA has long looked to life on Earth to guide its search for life on other worlds. Planets and moons that have hints of liquid water have always ranked high on the list of potential sites for life detection missions. In fact NASA’s summary of its strategy is: follow the water. But there’s now good reason to suspect that other kinds of chemistry could support life as well, the authors of this new report argue.

Weird life could differ from life as we know it in big or small ways. For example, while DNA uses phosphorous in its backbone, it might be possible to build a backbone out of arsenic instead, and life might exist in liquids other than water, perhaps ammonia or methane. The report even explores the possibility of life based on silicon, not carbon, although Mike Meyer who was not part of this study thinks that astrobiologists should limit their search to carbon-based life forms. “When we look in the universe,” he said, “the only compounds we see with more than six atoms are all based on carbon chemistry. That’s a strong hint that looking for carbon chemistry may be the best bet. There we have some idea what to look for.” The report calls both NASA and the NSF to fund research into weird life.

“Chemists need to investigate chemical possibilities for what life forms might take,” said one member of the committee, Steve Benner, who’s a Distinguished Fellow at the Foundation for Applied Molecular Evolution in Gainesville. Scientists should also continue to search the Earth for weird life. “There’s so much about Earth life we don’t understand,” says the panel’s chairman, John Baross, who’s a professor of oceanography at the University of Washington. Benner also said, “There’s good evidence that the life we know on Earth was preceded by a weird form of life.” It may have been based on RNA, a single stranded form of DNA. Although DNA based life out-competed earlier forms, RNA life may still exist in particular refuges.

One potential hiding place is deep below the ocean floor. “It’s an incredibly primordial world down there,” said John Baross. If you’re going to look for remnants of an RNA world, those are the environments you want to look in. To find weird life, however, scientists will have to build completely new types of detectors. There’s no question that the surveys of life on the planet we’ve done so far would have missed it.

The scientists also said that the possibility of weird life should prompt NASA to reorder its future missions. They’ve singled out Saturn’s moon Titan as particularly promising. The Huygens probe that visited Titan in 2005 found evidence for liquid methane raining down on its surface as well as a mix of water and ammonia seeping out from the interior. Since then we’ve seen large liquid lakes as big as the Great Lakes made of ethane, methane, and ammonia. These large bodies of liquid could conceivably support life, although not necessarily life as we know it. Nothing, the report concludes, would be more tragic in the American exploration of space than to encounter alien life and fail to recognize it.

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First week of January 2007

In case you are new to the subject of astrobiology or to this blog, I thought I’d start the year by looking back on the previous year and talking about the highlights in this subject of the year 2006. Well, obviously the big highlight would be if we’d found life on another planet. It hasn’t happened yet, folks. As we speak, Earth is still the only planet we know of in the universe. It’s a universe that think is filled with planets and many could harbor life, but we have no evidence yet. But there were some very exciting events of 2006 and I’ll go over my top list of ten in chronological order during the year.

One. Early in the year we witnessed the safe sample return from a comet for the first time with the Stardust mission. A thimble full of comet material returned to Earth representing pristine evidence from the solar system’s formation four and a half billion years ago. Scientists are studying it and learning a lot from it already.

Two. The next story, also in January, was the planet closest in mass to the Earth yet discovered. With over two hundred extrasolar planets known, most of them are Jupiter-sized or larger. This planet, announced in January, is a little more than five times the mass of the Earth, clearly Earth-like although in practice much hotter because of its close orbit to its parent star. It was found by the lensing technique rather than the Doppler technique that most extrasolar planets have been found with.

Three. The following month witnessed some grim news for astrobiology in the NASA budget. Astrobiology was disproportionately cut during NASA’s budget woes, getting a fifty percent cut on its research programs. That was brutal. It put missions like the Terrestrial Planet Finder on indefinite hold, and any chance of going back to Europa and certain Mars missions also took a dive. There’s still big uncertainty hanging over the NASA budget, but there was a popular outcry and even a clamor among scientists who are not astrobiologists to restore some of these cuts and not hurt a program that’s so popular with the public.

Four. In March there was evidence from the Cassini mission of geysers on the tiny world Enceladus, a moon in the outer solar system expected to be tiny and frozen. Only five hundred kilometers across, somehow water is kept liquid under pressure under the surface. The evidence of liquid water so far from the Sun on a tiny moon opens up the possibilities of life because liquid water is one of the key ingredients that life needs.

Five. In April there was an interesting story indicating evidence that the wave of heavy bombardment of meteorites in the first part of the Earth’s history occurred in a narrow window of time only a hundred million years long about 3.9 billion years ago. Since the early evidence of life on Earth precedes this date, there’s a possibility that life got started very early on the Earth and survived the era of heavy bombardment. If biology could have survived that kind of series of impacts, it again indicates how robust life might be in other inhospitable places in the universe.

Six. In June there was an interesting study from Australia of stromatolite colonies, that is bacterial mats, one of the oldest forms of life on the Earth. The study of these types of organisms from 3.5 billion years ago showed that they were amazingly complex, complete ecosystems. The fact that life had such complexity 3.5 billion years ago means complexity developed early, at least in terms of ecosystems even if the individual organisms were rather simple.

Seven. In July, there was evidence of lakes on Titan from Cassini flying by that large moon. These lakes are strange: they have no liquid water, they’re far too cold for that, but instead have ethane and methane, making scientists wonder how strange life might be and could it exist in liquid of this form?

Eight. August saw one of the biggest news stories at least as far as the popular media was concerned: the demotion of Pluto. Well, this is the one I’m least agitated about. Most astronomers consider Pluto an oddball, and for astrobiology it’s a small dead rock. Let’s get over it. In the end, who cares? It’s semantics for the most part. I know that’s an unpopular position with many people.

Nine and ten. In November, a pair of NASA news stories. The big news was that the shuttle will fly to fix the Hubble Space Telescope. That’s good for all astronomy, not just astrobiology. This followed on the successful shuttle flight from July 4 of also 2006. And the final story of the year, only a few weeks ago in December and probably the most important story, was the discovery that water on Mars has flowed recently. Images taken only a few years apart by the Mars Global Surveyor, now a defunct mission, showed that water has flowed. Changes in the topography on timescales of only a few years indicate that water erupts onto the surface, almost immediately evaporating or freezing. But such recent activity and the indication that water can exist onto the surface of Mars is very exciting and increases the suspense and the tension of going to Mars with more sophisticated instruments to try and find subterranean microbial life forms.

After I pulled this list together I ran across the list compiled by NASA’s Astrobiology Magazine, so I quote that for comparison, and there’s a fair amount of overlap. They ordered their stories by importance. According to NASA the tenth most popular story or most important story was the end of the Mars Global Surveyor, one of Mars’ most successful missions over the years. Number nine was the launch of the New Horizons mission to Pluto which will take almost a decade to reach that frozen planet, well, not even a planet now we know. Number eight was the arrival of ESA’s Venus Express at the planet Venus and the beginning of its large survey program. Number seven was Cassini’s continuing investigations of Saturn’s moon Titan with many interesting discoveries coming almost weekly. Number six was the discovery of a super icy Earth, a planet weighing thirteen times as much as the Earth, one of now over 200 extrasolar planets known. The number five story was the continuing mission of the Mars Exploration Rovers. They had their mandate and their budget renewed for a third time. The rovers have been extraordinarily successful and very popular with the public. You can follow their daily progress on NASA’s website. The number four story was the Mars Reconnaissance Orbiter which went into a stable orbit around Mars and started to send back stunningly detailed images of rocks as small as a small boulder, a meter across. This will map out Mars to make safe landing sites for the next series of missions that will land there. The third most popular story was the discovery of liquid water on Saturn’s icy moon Enceladus, probably broadening the diversity of solar system environments where there may be conditions hospitable to life. The second story was the collection by Stardust of particles from the comet Wild 2. And the top story, and I’m in agreement here, was the discovery of possible water flows on the surface of Mars within the past few years, really increasing the potential of microbial life on our near neighbor.

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