"Who are we? We find that we live on an insignificant planet of a humdrum star lost in a galaxy tucked away in some forgotten corner of a universe in which there are far more galaxies than people."
~ Dr. Carl Sagan
Dr. Sagan was a strong believer in the Copernican principle. I was in agreement with him at one point in my life.
Alas, the Copernican principle has fallen on hard times. Ironically, we have Sagan's pet project, SETI, to thank for much of the scientific discovery that is eroding the now outdated assumption that our planet is ho-hum and our star is humdrum. The ? Most stars in the galaxy are formed in dense nebula clusters like the Orion cluster. Turns out, after observing the Orion nebula cluster closely, that fewer than 10 percent of the stars have enough surrounding dust to form Jupiter like planets. To an astrobiologist, that's a problem. Giant planets like Jupiter play an important role in fostering life on rocky planets like earth.
So, take those 10 billion trillion stars and scratch out 90 percent of them as possible life sites. If Jupiter like planets were the only requirement for fostering life on a neighbor planet, then the numbers would still swing towards Copernicus. Of course, there are a lot more things that need to happen besides this one parameter.
The odds just went to a trillion trillion trillion to one. So much for humdrum ;) Be sure to thank God one more time for our special star.
I dunno, man. 10% of ten billion trillion is still an awful lot. :)
Posted by: tgirsch | July 23, 2008 at 17:37