|Posted: 2007-March-12 at 2:09pm | IP Logged
Unfortunately it's rather difficult to design an experiment that will detect life without making some kind of assumptions on its form, even more difficult to get someone to fund you to build it and send it into space.
While there may be lifeforms based on exotic chemistry out there, we don't have much idea if that's possible, or what would represent "food" or "lethally dangerous toxin".
I agree with you the current viewpoint is flawed (actually, I suspect there are rather more places with liquid water in the universe which don't have life than that do), and I don't think we're going to get anywhere with chemical tests for life. Maybe a microscope would be more useful to detect whether life exists in the regolith of an alien planet, but getting one of those to Mars/Europa/wherever is quite a challenge.
What we need is some kind of sample/return probe. Again, quite a challenging engineering prospect, but we've got samples from the Moon with such probes.