Number of contactable alien civilisations? 36

[WillBrink]

Within OUR galaxy.
Looking at one of Hubbles deep field images, that can be multiplied by how many million?
It's a bit overwhelming once the true scope and size is grasped....somewhat....

Come to think, times X.10 power 6 that significantly increases the possibility of getting abducted by some hot alien babe, no?

Hundreds of billions and that's within the observable universe. It's very possible there's far more. However, it's also far less likely we'd ever make contact outside our own galaxy.

[WillBrink]

I think this is right up there with declaring the size and chemical composition of exo planets based upon nothing more than gravitational wobbles of very distant stars. At best it's highly speculative.

If anyone took the time to read Rare Earth they would discover there are dozens of variables that are probably required for a planet to be habitable AND exist long enough for life to begin to say nothing of what is necessary for advanced intelligent life that forms civilizations of some kind to occur.

While there is the extreme numerical probability based upon the Drake Equation, when you plug in a lot of other considerations your likely numbers get really, really low. Right now the reliable number is 1 and until we actually have some kind of genuine supporting evidence (other than numerical probability) that number is going to remain 1. I don't care how many planets get defined as "in the habitable zone" or "capable of sustaining life" it's all just speculation right up there with Percival Lowell drawing maps of Mars and it's complex system of canals.

Agreed, but it's becoming less speculative at least as we become able to plug in some of the numbers to that equation with less hypotheticals. But mankind has always reached for what's beyond him with imagination and curiosity and filled in the hard numbers later as they could. Slowly but surely, it's becoming less hypothetical at least.

[SteyrAUG]

Agreed, but it's becoming less speculative at least as we become able to plug in some of the numbers to that equation with less hypotheticals. But mankind has always reached for what's beyond him with imagination and curiosity and filled in the hard numbers later as they could. Slowly but surely, it's becoming less hypothetical at least.

Right now, with everything we have and everything we know, the number is still 1.

Now don't misunderstand me. When it comes to belief, I find it incredibly, highly unlikely that we are the only planet in the entire universe with life or even sentient / intelligent life. I believe life happens everywhere it can be supported and while not a guaranteed outcome of driven evolution, I think intelligent life of some form is the eventuality of all life if enough time exists to permit it's development.

That is what I believe, but we have zero evidence to declare that life exists anywhere else but here. If we find fossilized microbes on Mars it will be incredible and we would finally have evidence that life happened someplace other than Earth and probably happens in lots of places.

I really enjoy theoretical science, especially when it comes to the nature of the universe and the possibility of life elsewhere and I was a huge fan of Sagan and his "imagine if" approach to science which makes one contemplate what might be possible, but we have to remain absolutely clear that these things are speculation and those other things are what we know for certain and there is a dramatic distinction between the two.

Otherwise what we are doing no longer qualifies as science and we have more than a few people doing that already and it undermines the actual discoveries and the knowns that we have been able to put in the "we know for sure" column.