Monday, October 26, 2009

Exoplanet indifference?

It is interesting how quickly humans can adapt to an environment. When Apollo 13 was heading to the Moon, and before the explosion that almost cost the lives of the astronauts on board, the public was already feeling familiar with Moon shots. It was no longer front page news, no longer worthy of extended TV coverage - in fact, it barely got covered at all, by comparison to Apollo's 11 and 12. The explosion changed all of that of course.

Has the search for exoplanets already begun to become familiar? Over 400 exoplanets have been discovered. When more are announced, it's almost met with a "Oh, isn't that nice. Honey, will you pass the salt? Hey, I hear it will rain tomorrow..."

Though what is helping to maintain some excitement is that the exoplanet search keeps getting more sophisticated and refined and finding smaller and smaller planets. We are even beginning to detect, even if just barely, the atmospheres of planets orbiting alien suns hundreds of light years away. Each new telescope that joins the hunt breathes in fresh life, and new excitement, into the search.

Rest assured that when a truly Earth-like terrestrial planet is discovered (an Earth-sized, or nearly so, terrestrial planet orbiting a stable star in the HZ), it will be an "explosive" discovery that will thrust the search for exoplanets back into the spotlight, especially if an atmosphere is detected and gives initial signs of being habitable (though even a good spectral analysis of an atmosphere probably can not prove the existence of life on the planet).


Anonymous said...

Spectral analysis can reveal trace gas compositions that could only be produced by life.

Mr. David Michael Merchant said...

Unfortunately, non-biological processes that can mimic the chemical by-product results of biological process do exist. In a large universe, with a large diversity of planets (and thus planetary composition and environments) detecting trace gas compositions that are normally associated with life will not be enough proof, at least not by itself. It will be very suggestive, and exciting, and will cause the planet in question to be observed and studied more closely, but I am doubtful the detection of those trace gasses alone will be enough for the scientific (and some members of the public) to accept it as conclusive proof.