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WillBrink
06-15-20, 10:32
How did they come to 36? Plugging ever more refined numbers into the Drake equation, they get 36 apparently. I had 38, but what do I know? But seriously, The the Drake equation is as much a thought experiment as anything until what get's plugged into it is not a WAG. However, knowledge of space and greater accuracy of the variables in that equation has improved greatly, making for seemingly improvements in accuracy. No doubt the margin for error is still enormous:

Scientists say most likely number of contactable alien civilisations is 36

They may not be little green men. They may not arrive in a vast spaceship. But according to new calculations there could be more than 30 intelligent civilisations in our galaxy today capable of communicating with others.

Experts say the work not only offers insights into the chances of life beyond Earth but could shed light on our own future and place in the cosmos.

“I think it is extremely important and exciting because for the first time we really have an estimate for this number of active intelligent, communicating civilisations that we potentially could contact and find out there is other life in the universe – something that has been a question for thousands of years and is still not answered,” said Christopher Conselice, a professor of astrophysics at the University of Nottingham and a co-author of the research.

In 1961 the astronomer Frank Drake proposed what became known as the Drake equation, setting out seven factors that would need to be known to come up with an estimate for the number of intelligent civilisations out there. These factors ranged from the the average number of stars that form each year in the galaxy through to the timespan over which a civilisation would be expected to be sending out detectable signals.

But few of the factors are measurable. “Drake equation estimates have ranged from zero to a few billion [civilisations] – it is more like a tool for thinking about questions rather than something that has actually been solved,” said Conselice.

Now Conselice and colleagues report in the Astrophysical Journal how they refined the equation with new data and assumptions to come up with their estimates.

“Basically, we made the assumption that intelligent life would form on other [Earth-like] planets like it has on Earth, so within a few billion years life would automatically form as a natural part of evolution,” said Conselice.

The assumption, known as the Astrobiological Copernican Principle is fair as everything from chemical reactions to star formation is known to occur if the conditions are right, he said. “[If intelligent life forms] in a scientific way, not just a random way or just a very unique way, then you would expect at least this many civilisations within our galaxy,” he said.

Cont:

https://www.theguardian.com/science/2020/jun/15/scientists-say-most-likely-number-of-contactable-alien-civilisations-is-36

ABNAK
06-15-20, 19:30
Just be careful what we ask for.....

ryanm
06-15-20, 20:57
Our luck they arrive to give us permanent anal fissures and keep us alive for a million years with constipation followed by diarrhea.,.

polydeuces
06-15-20, 23:45
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?

SteyrAUG
06-16-20, 00:17
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.

SteyrAUG
06-16-20, 00:19
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?

Really wanting Cat Women of the Moon to be a thing. That film filled me with much hope and promise as a 12 year old watching 1950s sci fi films.

The_War_Wagon
06-16-20, 07:02
Is that INCLUDING earth? "Civilized" might be a stretch these days - maybe that should be "35 civilizations."



http://youtu.be/T3AiWL-UHuY

FromMyColdDeadHand
06-16-20, 08:05
42


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Det-Sog
06-16-20, 09:26
Key word: Contactable. Someone better invent a "subspace network" like on Star Trek.

So then, any planet farther than 150 light years away from earth right now that might have optical and radio telescopes trained at the earth will see and hear NOTHING. Just camp fires and oil lamps back then. We barely started with a radio signature until just 100 years ago. That's not even across the room by astronomical standards. Now add that ALL of our radio signature gets washed out by the sun after just a light year or two. So, even someone 10 light years away with a SETI network pointed right at us, probably won't pick anything up.

Until someone else passes through the neighborhood, or WE travel to theirs, it's going to be awfully quiet.

WillBrink
06-16-20, 09:31
Just be careful what we ask for.....

Stephen Hawking was not a proponent of actively attempting to make contact with other civilizations for that reason. He felt if they were considerably more advanced, there was nothing to say they would not show up and take out chit.

WillBrink
06-16-20, 09:35
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
06-16-20, 09:39
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
06-17-20, 00:29
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.