Monday, October 19, 2009

400+ Exoplanets and counting

According to THIS article, 32 newly confirmed exoplanets have been added to the ever-growing list, thanks to the efforts of astronomers at the European South Observatory. Most significant here is the fairly large percentage of 'super-earths' discovered, planets that are much more massive than Earth, but are not big enough to be gas giants. If these are fairly common, than that means that smaller terrestial planets like the kind we are familiar with must be a standard feature in most star systems.

I would put a cautionary asterix next to the statement in the article by astronomer Alan Boss that, "The universe must indeed be crowded with habitable worlds." While I think most of us would indeed hope that's the case, there's still no real evidence for that. The universe seems to be a very hostile place, and even a plentitude of terrestrial planets does not automatically guarantee a plentitude of life. A lot can still go wrong in the billions of years that are needd for life to evolve, even if it does arise on any world. I'm not saying that life-bearing worlds aren't out there, I'm just saying we need more evidence before we can say that the universe is crowded or not with them

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