RE: Extraterrestrials
January 23, 2018 at 8:28 am
(This post was last modified: January 23, 2018 at 8:32 am by polymath257.)
First, if I were inclined to *bet*, I would bet that there at least has been other life in our galaxy. Given the number of galaxies, I would *bet* that there is other intelligent life out there.
But that is very much NOT the same as saying we have been visited by other intelligences. I find that to be rather unlikely.
Here's why.
Our species has been able to send radio signals for about 100 years. We have had agriculture for about 10,000 years. How much longer do you think we have as a species? Given how intent we ar at destroying ourselves, I'd say another 10,000 years is optimistic at best. That mens we have 20,000 years of being technological enough to have agriculture.
If that is typical, how likely is it that the 20,000 years for humans overlaps with the 20,000 years for another intelligent species in our galaxy? Remember that things like galactic rotation take 100 million years and star evolution takes billions of years. The sun is about 5 billion years old and it is only in the last 10,000 years we have had agriculture in our solar system.
So, my guess is that life (bacterial life, that is) is fairly common. But multi-cellular life, and intelligent life are, almost certainly, much less common and the likelihood of overlap and actual contact is low.
That was one of the first transmissions that was fairly powerful, yes. It was 80 years ago, which means it has reached places up to 80 light years away. Those are the *close* starts in our galaxy. Remember our galaxy is 100,000 light years across. We have signaled our presence to only a very small fraction of our galaxy.
And, like I said above, whether we even overlap with other intelligent species in our galaxy is a doubtful thing.
But that is very much NOT the same as saying we have been visited by other intelligences. I find that to be rather unlikely.
Here's why.
Our species has been able to send radio signals for about 100 years. We have had agriculture for about 10,000 years. How much longer do you think we have as a species? Given how intent we ar at destroying ourselves, I'd say another 10,000 years is optimistic at best. That mens we have 20,000 years of being technological enough to have agriculture.
If that is typical, how likely is it that the 20,000 years for humans overlaps with the 20,000 years for another intelligent species in our galaxy? Remember that things like galactic rotation take 100 million years and star evolution takes billions of years. The sun is about 5 billion years old and it is only in the last 10,000 years we have had agriculture in our solar system.
So, my guess is that life (bacterial life, that is) is fairly common. But multi-cellular life, and intelligent life are, almost certainly, much less common and the likelihood of overlap and actual contact is low.
(January 23, 2018 at 5:27 am)LastPoet Wrote: Correct me if I am wrong, but the first transmission to reach nearby stars was Hitler speech at Nuremberg.
Quite the vacation pamphlet. Babies soiling their own craddle, with no aim.
That was one of the first transmissions that was fairly powerful, yes. It was 80 years ago, which means it has reached places up to 80 light years away. Those are the *close* starts in our galaxy. Remember our galaxy is 100,000 light years across. We have signaled our presence to only a very small fraction of our galaxy.
And, like I said above, whether we even overlap with other intelligent species in our galaxy is a doubtful thing.
