Sunday, March 6, 2011
NASA has dropped another bomb, making what seems to be the strongest claim ever for the existence of extraterrestrial life. The claim is that they have found fossilized bacteria in a meteorite fragment.
The Village Elliot has made a cursory examination of the original paper, and here's what I can tell you:
a. This is not the first time that NASA has made an extraordinary claim. Some fifteen years ago, another meteorite fragment was proposed as a possibilty for extraterrestrial life. In that case, however, it seemed that the meteorite had the right sort of catalysts in it to promote the growth a ceramic fibrils that might look like bacteria. The Village Elliot himself had made such materials, which are related to carbon nanotubes. Briefly, all you needs is the right kind of iron catalyst, and if you heat it up to the point where it is nearly molten, the catalyst will cause ceramic nanotubes to grow, They look exactly like the NASA "fossils," so I figured that they are probably not fossils, but ceramic nanotubes grown as the meteorite washeated, possibly during reentry.
b. The current generation of claimed fossils is a bit more impressive. They are the right size to be bacteria, and indeed the authors (Hoover et al.) believe that terrestrial bacteria may have been seeded from comets based on the resemblances. I wouldn't rule it out,but on the other hand, I've seen similar large diameter structures form when the conditions are right. So, the question is whether these things *are* fossil bacteria, or whether they just look liike they are. On the grounds that extraordinary claims require extraordinary justification, I'm not buying it just yet. In fact, I'd like the opportunity to put the same materials on a plate and heat them up to the temperature regime at which these nanotubes form, and just see what we get.
c. Although the leader of the current team, Richard B Hoover, is a veteran scientist, he was one that on record supporting the claimed fossil bacteria circa 1995 from McKay et al. That suggests that he is a bit overeager to believe in the fossilized bacteria theory.
d. This new claim comes on the heels of another spectacular claim, for a fundamental new life form discovered on earth that doesn't need phosphorous to survive, using arsenic instead. A number of people think that that claim was made prematurely as well.
e. NASA is also out in front on the issue of global warming. Rather than striving to be an impartial arbiter, as one might expect from a government agency, NASA seems to increasingly view its role as an advocate for certain controversial theories.
All that said, I think the current article is much more formidable than it's predecessors. I've written to the Journal of Cosmology and asked to be put on the panel of reviewers being assembled. The role I've proposed for myself is to see if it is possible to make these kinds of structures by taking these materials and sticking them in an oven and heating them up. I'm confident that some kind of fibers will indeed grow spontaneously. What I'd like to know is if the meteorite structures have specific features uniquely identified with bacteria, that can not be duplicated in my lab.