Two kinds of astrobiology stories are in the wind this morning. One of them has to do with the weekend eruption of stories concerning evidence of fossilized life inside a meteorite. The other deals with scientific investigation off-planet, and although sparsely covered, it’s the one with the greater significance for finding life elsewhere. But first, let’s get Richard Hoover’s paper about meteorite life out of the way, for the growing consensus this morning is that there are serious problems with his analysis, especially as regards contamination of the sample here on Earth.
I have no problems with the panspermia idea — the notion that life just may be ubiquitous, and that planetary systems may be seeded with life not just from other planets within the system but from other stellar systems entirely. It’s an appealing and elegant concept, but thus far we have no proof, and despite what Dr. Hoover is seeing in samples from three meteorites, we still can’t definitively say that we’ve found fossilized microbes from any biosphere but our own. The skeptics are weighing in loud and clear, and Alan Boyle has collected many of their thoughts.
I want to send you to Alan’s Cosmic Log for the bulk of these comments, but let me lift one from Dale Andersen (SETI Institute) to give you the gist. Andersen acknowledges the excitement of the story if it could be proven true, but he’s worried about the fact that Hoover’s work is not playing well within the scientific community, and he is waiting for serious peer review:
“Peer review will include the examination of his and other scientists’ data and logic, and not until that has occurred will we see how the story unfolds. Occam’s razor will eventually be used to slice and dice the carbonaceous chondrites used by Richard to present his evidence. Is it more likely that upon looking into the interior of a meteorite collected on Earth and finding photosynthetic cyanobacteria, which on Earth are usually found in water or wet sediments, their presence is due to contamination from terrestrial sources or that it formed inside the parent body of comet or asteroid in deep space? There will be many other possibilities to rule out before one arrives at the extraterrestrial answer.”
You can find Hoover’s “Fossils of Cyanobacteria in CI1 Carbonaceous Meteorites,” in the Journal of Cosmology, Vol. 13 (March, 2011), which is available online.
Addendum: Be sure to check out Philip Ball’s “The Aliens Haven’t Landed,” published online in Nature today.
Meanwhile, Around Europa
Hoover’s ideas will be considered in a much longer process of investigation as other scientists analyze his evidence, but as is always the case, let’s be cautious indeed about claiming life from elsewhere in the universe. None of which is to argue that we slow down our investigations into such life, but alas, in the other astrobiology story of the morning, our chances of getting to a prime site for a closer look are taking a hit. Tightened budgets are threatening to push the Jupiter-Europa Orbiter further into the future, joining other big missions on indefinite hold.
The Jupiter-Europa Orbiter was conceived as part of a collaborative campaign between NASA and ESA called the Europa Jupiter System Mission, a two-spacecraft investigation originally planned for a launch around 2022. The troublesome news about the NASA contribution comes from a new report from the National Research Council, which while recommending a suite of flagship missions over the decade 2013-2022, also takes pains to note that budgetary constraints could limit NASA to small scale missions of the New Frontiers and Discovery class in that period. Steven Squyres (Cornell University) chaired the committee that wrote the report:
“Our recommendations are science-driven, and they offer a balanced mix of missions — large, medium, and small — that have the potential to greatly expand our knowledge of the solar system. However, in these tough economic times, some difficult choices may have to be made. With that in mind, our priority missions were carefully selected based on their potential to yield the most scientific benefit per dollar spent.”
The priorities are there, but throw in the fact that these recommendations were informed by NASA’s 2011 projected budget scenario — and that the 2012 projections are less favorable — and you can see that the Jupiter Europa Orbiter (JEO) is in trouble. The JEO comes in as the second priority for NASA’s large-scale planetary science missions, after the Mars Astrobiology Explorer Cacher (MAX-C), and while the report notes how promising Europa and its subsurface ocean may be for astrobiological studies, it says that JEO should fly only if NASA’s budget for planetary science is increased and the $4.7 billion mission is made more affordable.
Expect the launch of a Europa orbiter between 2013-2022, then, only if both the mission and the budget outlook change significantly. The same holds for the Uranus Orbiter and Probe, an exciting mission concept that would deploy an atmospheric probe to study this interesting world while the primary spacecraft orbits Uranus and makes planetary measurements as well as flybys of the larger moons. Space News notes the threat to all three missions, citing remarks by Jim Green, director of NASA’s Planetary Science Division on March 3:
…because the decadal survey’s findings are based on NASA’s more generous 2011 out-year funding projections, rather than the declining profile laid out in the 2012 budget request, it is unlikely the agency can afford to embark on any new large projects in the coming decade. Green, speaking March 1 at a meeting of the NASA Advisory Council’s planetary science subcommittee, warned members not to expect the funding outlook to improve.
Looking to Smaller Missions
The upshot of all this is that the flagship missions with the most interesting astrobiological profile are on hold in an environment favoring only small- to medium-class probes. We still have one flagship mission, the $2.5 billion Mars Science Laboratory rover, set to launch later this year, but the grim truth is that the MSL will probably be the last planetary flagship mission for quite some time. What had appeared a promising funding prospect in the 2011 NASA budget request has reversed itself with the administration’s 2012 request (released in mid-February), which shows a decline in planetary spending after 2012 that will not support these larger mission plans.
So while we have support for both Mars sample collection and the Europa orbiter in the report, the reality is that the money is just not there. For the time being, then, realistic outer planet prospects focus on Juno, a mission slated for launch this summer that will spend a year orbiting Jupiter. The solar-powered vehicle will orbit Jupiter’s poles 33 times to study the planet’s atmosphere, structure and magnetosphere. Juno is currently undergoing environmental testing at Lockheed Martin Space Systems near Denver.
We’ll wait, too, to see what medium-sized missions NASA will select for the New Frontiers program, which would benefit from the trimming of the flagship missions. The agency is selecting one New Frontiers mission now and the committee recommends two more missions be chosen for the 2013-2023 period. Possibilities include a Jupiter mission to Io and a trojan asteroid rendezvous. The Discovery program of low-cost, highly focused planetary science missions also receives the report’s blessing as hopes for the big missions are deferred.
Pre-publication copies of Vision and Voyages for Planetary Science in the Decade 2013-2022 are available from the National Academies Press.