[jpwagner]

Point taken. But I can't help but be reminded of this: http://xkcd.com/373/

Anyone who feels tricked that there were no aliens found doesn't have their head on straight :)

By your rationale, would anything be called Astrobiology?

[Archaeum]

I guess I tend towards thinking of astrobiology as the subset of biology dealing with life beyond Earth--a convenient and arbitrary definition, perhaps. In any case, under this definition, with no validated extraterrestrial life, astrobiology would be a largely theoretical science or a line of philosophical inquiry. But if that's too narrow an interpretation, maybe this indeed is an example of experimental astrobiology. Hence, I may have overstated my position when I said this is not astrobiology.

At this point, however, I fear I'm drawn towards philosophical digression. It seems the motivation of the scientist comes into play because she could end up with the same results whether she is a) looking for insight into how life could exist elsewhere in the universe or b) studying life in extreme conditions on Earth. The impetus and interpretation become the categorizers (in practice, I don't think it's too cynical to link this to funding source). On the broader question, I should perhaps defer to the epistemologists--does the nature of knowledge change depending on why it was sought or what is made of it?

Back to the question, what would I consider astrobiology? Well, if life or its precursors were found on Mars or a comet, that might work for me. But what happens when it falls to Earth? I don't know; I've never been particularly comfortable with the blurry divisions between disciplines anyway, so if I consider the dividing line between, for example, psychology and sociology to be tenuous, how am I supposed to feel in this instance? The thing is, knowing what to call it doesn't really affect our ability to understand or use it, it just changes the way we talk about it--which may be important, I grant. But this brings me back to the communication aspect. And as far as that goes, I feel like I've gone through a lot of words without saying much. Therefore, let me summarize like so: I understand why they call this astrobiology; I probably wouldn't call it that myself; most importantly, I think many people will be expecting something else.