q_bot_w11, a few things with SETI that mean they haven't found anything, and consequently, are wasting our CPU cycles
Assume for a moment that their solar system/planet + star came into being about the same time as our solar system... about 10 billion years ago IIRC... the whole universe is estimated to be about 16 billion years old, with about a few billion to form all the elements from hydrogen fusion, and then another billion or so for the gases to come togehter, so that's a fairly okay assumption
Now assume that their planet took about 3.5 billion years to cool down properly, like ours did, and then another billion years for it to start producing intelligent life...
That's about 5 billion years for that planet's population to send out a signal a few times, give up trying, cause global warming, polute the atmosphere and cause a nuclear winter killing everyone on the planet... not to mention that their star might have gone nova before then...
Now, assuming they will use the same frequencies that have been scanned (that is, of course, assuming they know about and are using radio waves), assume they are sending out a signal in the first place...
That's a few assumptions already!
Now, the closest galaxy to us, the andromeda galaxy, is either 2 or 2 million light years away... one light year = 9,467,280,000,000 km, or 5,883,952,765,693 miles
When you send out a signal like that, unless you know where you are sending it and can channel the wave in that direction, you are sending it in all directions...
Signal strength is proportional to 1/(distance)^2... i.e. when the distance doubles, the signal strength drops to a quarter of what it was (I know you proably know this already, just making sure)... If the signal strength at 10km is 150, then the strength at one light year is something like 150/2^31...
Now, even assuming that against all these odds, we find a signal we BELIEVE is from another world, what do we do? Try to decode it? How? Send one back that probably won't even get noticed?
So the SETI project is looking for signals that are weak beyond comprehension, in the midst of a load of radio static, that we have no proof exist, or that we are looking for the right signals in the right place.
Oh and did I mention that the only planet we've found that can possibly sustain life so far(we "found" it by measuring gravitational wobbles caused by the gravity of the planet affecting the course of the light given off by the star it orbits) is something like billions of light years away? That's a real weak signal. Oh, and that particular planet has only one side that ever faces the star due to the gravity caused by it, and the winds this creates makes Red Spot on Jupiter seem like the ideal place to spend a picnic... Or whatever that big storm is called...
Because it's billions of light years away, we won't receive that signal, EVER! In 4.5 billion years our sun will have taken us out before contracting into a dwarf, that's assuming we make it that far as a species...
No point looking there, let's go spend a loada government money finding another planet that we'll never even see (due to the relative brightness of the star and the distance it is away) that we'll never prove has life on it, that could be used for something like a hospital...
Suddenly crunching proteins for a possible cure for Alzheimer's seems mighty attractive, almost worth it
IntelMole