Is the current Kepler data, which suggest that ~1/3 of stars in the galaxy have at least one planet, a lower limit ? After all, the mission still has more data to collect and would not yet have been able to claim a secure detection of a solar system having the same planetary configuration as our own.

our solar system is unusual

Well, as of date _all_ found systems are unusual. Kepler found one with _only_ planets between Earth and Neptune (IIRC).

This is why astronomers are now preparing to buckle on research on planet system formation. There seem to be many ways to form a system, and many outcomes.

Until we have more statistics and/or models it seems premature to make claims on the precise statistics to pick individual systems. (Which btw I note wasn’t presented – how rare would the SS be when picked out of the given distribution? Not so rare, I think.)

a better estimate is at least 10^8, if not 10^9.

That is what I get too, but it depends on how you define “Earth like”. I was happy with 0.5 -2 Earth radius in habitability zones.

Paul Davies is an impressively

outspoken deist. I can’t read anything from him without observing the religiously motivated need to find humans rare compared to bacteria, whether it is Rare Earth or (paradoxically) Shadow Biospheres.

A more healthy read may be the one recommended in my astrobiology course, “If the Universe Is Teeming with Aliens… Where Is Everybody? Fifty Solutions to Fermi’s Paradox and the Problem of Extraterrestrial Life”, Stephen Webb.

Basically, I think they are saying that there could be a million planets that could *potentially* support life *as we know life to exist as.* But what compels me is what the NEXT satellite thingy will bring.

Think about that for a second. Within ten years or so (my hope at least) we’ll probably be able to determine things like atmosphere and colors of distant worlds. At that time, it would be appropriate to review the material. But for now, saying there are likely millions of earth potentials is not a bad statement.

Edit: If they spoke about this in the videos, then my apologies. I cant hear them right now.

The idea that a) there ought to be intelligent life out there b/c it’s here on earth and there are so many stars in the galaxy and b) WTF are they? seems to be less of a paradox than a puzzle for which there has been an inordinate amount of speculation.

Thanks very much for talking about this work I did with Jer Thorp, who deserves the bulk of the credit. I’m wondering, though, if you could perhaps update your main link so that it points to my initial post on BoingBoing (http://boingboing.net/2011/02/08/a-new-view-of-the-ga.html), where all this originated, instead of second-hand sources.

Cheers!

Lee Billings

For those interested in the best single source for the various arguments regarding the possibility of other “intelligent” life in the universe (including a discussion of the Fermi paradox), I recommend the recent book by Paul Davies, The Eerie Silence.

http://www.wbabin.net/science/anderton8.pdf

http://www.hiddenmysteries.org/mysteries/life/quantum.html