Science a GoGo's Home Page Forums General Discussion Not-Quite-Science Forum Extraterrestial Aliens?

Lord Martin Rees, President of the Royal Society, Astrophysicst, Cosmologist, ex director of Jodrell Bank telescope , etc,etc.
Said yesterday that "The existence of extra terrestrial life may be beyond human understanding."
That "Aliens could be staring at us in the face, but we could never recognize them"
He made the remarks shortly after hosting the national science academy’s first conference on the possibility of alien life.
"The problem is that we’re looking for something very much like us. There could be life and intelligence out there in forms we can’t conceive.
In the same way that a chimpanzee can’t understand quantum theory, it could be there
as aspects of reality that are beyond the capacity of our brains.”

Dr Frank Drake, the world’s leading “ET hunter”, told the conference that satellite TV and the “digital revolution” was making humanity invisible to aliens - by cutting the transmission of TV and radio signals out into space.
The Earth is surrounded by a 50 light year-wide "shell" of radiation from analogue TV, radio and radar transmissions.
These signals have spread far enough to reach many nearby star systems,...but they are rapidly vanishing now we transmit in digital technology, according to Dr Drake.
"Digital transmissions, will now only look like noise to any observing aliens"

http://royalsociety.org/News_WF.aspx?pageid=4294969624&terms=Martin+Rees

Thanks for the info Mike. Lord Rees' comments are often very thought provoking.

"...it could be there are aspects of reality that are beyond the capacity of our brains.”

Most likely true, I think, but it's beautifully humble, coming from one of the best minds on the planet.

Off topic, but I'll take the opportunity to mention this downloadable 11 page PDF file:

Lord Rees: The world in 2050

http://www.21school.ox.ac.uk/downloads/events/LordReesSpeech.pdf

[quote=Mike Kremer]

That was a fantastic read, it should become a discussion requirement for any Science Forum.
Thank you for bringing this famous Cosmologist thoughts to SAGG.

[quote=Mike Kremer]
Welcome Konark123 to the SAGG forum, I am interested your three questions.
Which I would like to simplify, to the following (with your permission)

"Do Aliens really exist, and how can we recognise and get to know them?"

Here are my quick thoughts.
We cannot know whether Aliens, exist.....until we find them.
And of course we have certainly been looking for them, using a number of interesting methods.

To those Aliens that we think are intelligent and have a civilization as advanced as our own.....we have sent out a number of high powered radio signals, into space, in the hope that those intelligent aliens will answer us, eventually.

So just how are those intelligent fish like Dolphins, swimming in the warm seas of some remote planet, going to reply to us?
How will those tiny mud loving slimey Alien worms go about replying to our radio signals?
Well they cant ever reply can they? They would'nt even recieve our radio signal, since it would be absorbed by the wet mud and ocean waters of that dtstant Planet.

This means that our high powered radio sinals sent into space could'nt possibly be directed to that type of life.
So what type of Alien do we think is out there?

For an Alien to recieve radio signals, it means it would have had to evolved out of the seas, and to have
constructed some sort of recieving antenna, on dry land?
So even if these radio recieving Aliens heard a few whistles of music or snatches of code..... would they percieve
that it was a product of us human aliens? No, of course not.
No I expect any real advanced intelligent Aliens would be just as secretive as ourselves, and just listen for signals?
Prehaps they have got their own Seti listening program, and 'antenna farms' directed at the most promising Star systems.....just as we have?

I said secretive, because listening does not draw attention to ourselves.
If we set up a 'Laser lighthouse' to advertise our presence, we might just regret it one fateful day?

Seth Shostak, the senior astronomer at the Seti Institute said "We have had the Biology of life for 4 billion years, and radio telescopes for 40 years, thats one in a 100 million". If the technological window for Aliens is as short as ours, then we might have to transmit to a 100 million Earth type planets.....before any one hears us.
And thats not even factoring in a reply.
Unfortunately Konark123, you are not going to get your answer within our lifetime.

Prehaps the only definitive proof of intelligent Alien life would be, to actually
see and photograph some Alien structures.
It should be possible to photograph, concrete, or metal buildings, or towers. Prehaps dwellings that gave them protection against violent weather systems?.

By using two or three (nuclear powered digital cameras)capable of skimming around our eight Planets, 3 mini planets (Pluto is one) and 140 (approx) Moons in our own Solar system, at about 20 miles high.
They could send back digital pictures which would enable us to see any Alien structures that might be out there?
They might turn up a few surprises. The high definition pictures would be much cheaper than landing men upon Mars or similar. And be infinitely more interesting in the long term?

Hi, Konark123

Do aliens exist? We don't know; but is it likely that they do? To me, it's laughable to suppose that we are the sole inhabitants of the cosmos capable of asking the questions. In our galaxy ~ 4E+11 stars. In the observable universe ~ 1E+11 galaxies. Total stars ~ 4E+22, or 40,000,000,000,000,000,000,000. Then factor in about 10 billion years of second (and subsequent) generations of star systems containing the known necessary raw materials for life as we know it.

Will we ever find an E.T. tech civ? Maybe, but I have doubts. I surmise that while intelligence may be rare, intelligence + technology may be extremely rare owing to short lifespan, where high technology >> population explosion >> destruction of habitat/depletion of resources >> famine/disease/war >> total destruction of civilization. Perhaps you could say that, for tech civs, the dawn of technology (Type 0 civ) is an initiation test - a proving ground in the evolution of a species toward mastery of themselves and their environment. A civ that has managed to survive it own technology (Type I or higher) may be capable of choosing not to be discovered by a warlike species on the brink of self-destruction.

How would we know? Perhaps by receiving an intentional radio communication. Or by detection of signals inadvertently disseminated like our TV and radio broadcasts. Maybe by tell-tale chemical signatures revealed by spectroscopy.

Like you rede, I just cannot believe we are the sole planet to have given rise to sentient life. Were dinosaurs sentient though? They certainly could neither send nor receive radio messages*, like Mike suggests in his remarks about about the slime worms.

rede-Your depressing second paragraph has forced me to consider that it is probably true that technologically advanced civilisations hold the seeds to their own destruction. Only such a civilisation could contact the others out there, and going on our environmental efforts over the years there would not be much left for the aliens who reply to communicate with. We certainly lack self-mastery!

Perhaps our best bet is that a developmentally advanced civilised bunch of space explorers could give us a hand out of our present problems. However since they themselves would have had to have passed through Type 1 unscathed it's not looking promising.

Maybe however, the biggest danger is that we would not be able to detect or recognise aliens. Is it possible that life forms could evolve that are not carbon based, and would we know what they were if they did?

*having re-read this I am hoping I am wrong, maybe there was a Marconi-saurus tapping away on its crystal set!

If the argument has any merit at all, the upside is that surviving civs will have proven to be the best adapted, not just in intelligence but psychologically and socially too. If we are to survive and grow-up to join those (thus far hypothetical) mature civs, then we have to perform a few miracles.

I sometimes wonder that too. I think Odessy 2000 had some sort of giant bubble organisms floating in the atmosphere of Jupiter. Even if they were carbon based they might be on a much larger or smaller scale than us.

It seems like a low gravity planet would be conducive to larger plants and animals. But such a planet would also be smaller so they might run out of space much quicker than us. Similarly a high gravity planet might have small aliens who would find it difficult or impossible to fly into space.

Carbon is unique in its tendency to form a rich molecular variety of long chains and rings that serve as a basis for complex compounds, many of which have been detected in interstellar space ***.

Silicon of often said to be the next best alternative to carbon. Yet, despite there being about 1000x more silicon than carbon in the Earth's crust, it failed to compete here. That would seem to lend weight to the argument that where there's carbon, complex molecules will most likely be carbon based. Several alternatives besides silicon have been suggested, including nitrogen+phosphorus, ammonia, and hydrogen fluoride. In the absence of carbon, one of those might do the trick; but carbon would be the chemist's choice, and it seems be to just about everywhere.

***
Life's Building Blocks 'Abundant in Space':
http://www.space.com/scienceastronomy/051018_science_tuesday.html (2005)

Complex organic molecules detected in interstellar space:
http://www.scientificamerican.com/blog/post.cfm?id=complex-organic-molecules-detected-2009-04-22 (2009)

Meteorite Crammed with 'Millions' of Organic Compounds:
http://news.discovery.com/space/meteorite-crammed-with-millions-of-organic-compounds.html (Feb 15, 2010)

Well maybe it is just as well that we are in fact a carbon based life form-- it may help our survival! Thanks for the answer rede, I have often wondered about that, and with the discovery of the presence of carbon virtually everywhere it looks as though it may be necessary for carbon molecules to be present in order to enable life to form.

Certainly the theory of comets carrying 'life' through space seems to gain credence now. That seems to be more likely than any of us reaching Type 1 civilisation.

My guess is that if life arose in the absence of carbon, then the organisms would remain simple and of limited diversity. If that had happened on earth, there might have been no opportunity for the evolution of a fish, let alone the staggeringly complex brain supporting the human level of intelligence. Still, that's only a guess. I'd be interested in an expert view (any links? )


Right. It seems that wherever complexity is possible it will probably occur, given time. And from the evidence of comets, meteorites and interstellar dust clouds, the greatest complexity results from the electrical properties of the carbon atom.


Yes, it does look that way given our species' track record and the current status of the planet we've re-made for ourselves. It's the logical prognosis. That said, I actually feel optimistic (so much for emotion, eh!). What I feel, or intuit, is that our descendants will pull through with flying colours. All we have to do is get the ball rolling in the right direction. I feel confident that we'll succeed, perhaps because so many have already started to work at it. It doesn't require any fundamental adjustment to human 'nature', just an awareness of the big picture and a correspondingly enlightened self-interest coupled with due care for our children's children.

I disagree with Ian McEwan (see signature below). What we often call our 'nature' is a crude and stereotyped caricature of human behavioural response to the environment, often cited in support of defeatist arguments. In reality, that behavioural response is flexible, so I don't think it's the limiting factor. Rather, I think the limitation is in culture and society - but both seem to be evolving in a generally positive way by virtue of the flexibility of our 'nature'.

Mike Kremer wrote

I have just found and re-read this old interesting disscusion.
Not a lot to contribute at this time, apart from these
two 'YouTube' videos.

Astronaut Dr Edgar Mitchell, (who walked on the Moon)

http://www.youtube.com/watch?v=mVV6u-Y2XZU&feature=relmfu

and, a couple of Goverment officials

http://www.youtube.com/watch?v=IeLtVp2FOqQ&feature=related

Today,three months later (12/05/12)
I have found and added yet another 'sensational' YouTube video.
This time from Russia about a buried Alien Saucer? Hmmm?

http://www.youtube.com/watch?NR=1&feature=fvwp&v=ZnWN31z6RKg