Regarding this story - Is there anybody out there?
- First, the Drake Equation called, they want their calculations back.
- Second, 1979 called, they want their song lyrics back
- Third, the journalistic standards on this article are mind-numbingly bad…. A 0.01% chance that life develops????
- That’s per-planet. Think about that for a moment. How many stars are there in the Milky Way galaxy alone?
- Between 200 and 400 billion.
- How many of these are similar to our Sun?
- Between 200 and 400 billion.
- So (and this goes back to the Drake Equation) - how many of those stars have planets?
- How many of those stars have planets in the habitable range
- Unknown, but at least a few we’ve found so far appear to be in the potentially habitable range - Let’s say 1%, based on the fact that 3 out of the 287 we’ve found seem to be close to livable.
- That’s per-planet. Think about that for a moment. How many stars are there in the Milky Way galaxy alone?
Given all of these facts and estimates. How many Sun-like stars in the Milky Way?… Assuming 300 billion stars total, that’s 45 billion Sun-like stars. How many of these have planets?… About 10%, or 4.5 Billion. How many of those have planets in the habitable range? 1%, or 45 Million.
Yes folks, based on our latest understanding of the Milky Way galaxy, there are 45 million planets out there capable of supporting life.
Now, according to the initial article, only 0.01% of those will have intelligent life and civilization… That would mean there are “only” 4500 civilizations in the Milky Way galaxy.
My ancillary was always: “well, where is everybody?” followed by “well, how old is the Universe, and what numbers should we plug into the Drake Equation?” followed by “what if everybody else, once their culture matures, stops broadcasting anything because they all use fiber etc.”
So, the more recent estimates of the age of the universe.. 2-2.5 times the age of our solar system, put things in a new light. There could be 4500 planets developing intelligent life, in that case, and it could just happen that none of them started blasting TV signals of their Olympic games into space at the right time for us to see the signals.
If the Universe was very old we ought to be awash in evidence of other civilizations.. or not, depending on the odds.
Comment by Walter R. Moore — April 18, 2008 @ 3:56 pm
Ancillary to my ancillary: what proportion of intelligent life survives past the moment where it can destroy itself through war or by over-consuming planetary resources?
We desperately need a control group for that experiment, but we only have one test subject so far.
Comment by Walter R. Moore — April 18, 2008 @ 3:58 pm