by Bjorn Keizers » Sep 18, 2004 @ 4:05pm
I don't doubt for a nanosecond that there are alien civilizations out there.
Have any of you ever heard of
It deals with the possible number of alien civilizations *just in our galaxy* and it uses the lowest possible estimates. It goes something like this:
N = N* fp ne fl fi fc fL
How many stars are in our Milky Way galaxy?
- around 100 billion
What percentage of those have planetary systems?
- current estimates are between 20% to 50%
Of those that do, how many could sustain life?
- current estimate: 1 to 5
If they do have life, could it evolve?
- impossible to guess, but let's say 1%
If it does evolve, what is the chance it'll be intelligent?
- Again, impossible to estimate for certain, say
another 1%
What percentage of those have means and desire to communicate?
- estimate around 10-20%
And the last one: If they exist, if they communicate, what are the odds that they will survive in the long term? What if they communicate and their sun goes nova before we hear their message?
In the end, you get the number of possible civilizations with which we could communicate. If you take the really, really low estimates, you still end up with a reasonable number of civilizations.... in our home galaxy...
I refuse to accept that we are the only intelligent life out here. It'd be an awful goddamn waste of space.