Nice SETI article on the Fermi paradox

murrayp4

http://www.seti.org/page.aspx?pid=678

shizz

The paradox is very interesting but I just can't comprehend the thought of us being completely alone in the universe.

Beeker

Alone! not a chance. It would be far more incredible if we were the only intelligent species in this immense universe.

gbee

SETI and other sky watchers are now concentrating on planets with magnetic fields like ours.

Seemingly our type is life cannot evolve without this sort of protection and for occupying existing planets later on, a planet that is otherwise M class but does not have a protecting magnetic field would necessitate massive protective shielding to be localised or even and underground existence.

Zubeneschamali

gbee wrote: »

SETI and other sky watchers are now concentrating on planets with magnetic fields like ours.

Fascinating.

Can you tell us how you imagine they can measure magnetic fields over interstellar distances?

gbee

Zubeneschamali wrote: »

Fascinating. Can you tell us how you imagine they can measure magnetic fields over interstellar distances?

I don't imagine anything and I did not mention anything about measurements. The planets can't really be seen but wobbles and shadows help to indicate the presence of mass which may be a planet.

After that the detection of aurora which does show up on radio telescopes makes this a subject of interest. All human-like-life potential planets are broadcasting to the universe.

It narrows the search for native planets, humanoid life on other planets would be visitors and possibly living underground so we'd never find them.

Zubeneschamali

gbee wrote: »

After that the detection of aurora which does show up on radio telescopes makes this a subject of interest.

So radio telescopes can detect aurorae on planets in other stellar systems?

gbee

Zubeneschamali wrote: »

So radio telescopes can detect aurorae on planets in other stellar systems?

I've no idea, I just made it all up.

slade_x

Zubeneschamali wrote: »

Fascinating.

Can you tell us how you imagine they can measure magnetic fields over interstellar distances?

If your interested in the subject, you can check out this pdf entitled

Magnetosphere Emission from Extrasolar planets

And even:

First Evidence of an Extra-Solar Planet with a Magnetic Field

Discodog

One conclusion from Fermi is that it is impossible to travel at near to light speeds which would explain why we are not aware of other life.

It's definitely out there but people cannot comprehend the distances.

maninasia

What is 'near' to light speed? 0.9, 0.8? What about if you travelled at 0.5 light speed? Since the galaxy is 100,000 light years across I can now travel across the entire galaxy in 200,000 years.

What is time but a concept. To understand this think of the life of a May Fly and your life of possibly a hundred years. What is time to something that can live forever or sleep forever? What is time if the universe always existed and always will?

Surely this type of 'rare earth' argument is antropomorphic thinking at it's worst. Let's examine why we need a magnetic field, to protect us from the 'damaging' solar radiation. Well surely plants and animals can evolve to avoid this. Oh wait a second, they didn't even need to do that because they already evolved in a handy place that covers 70% of our planet called the ocean duh!

maninasia

murrayp4 wrote: »

http://www.seti.org/page.aspx?pid=678

The paradox is not really a paradox at all. It can easily be explained by the fact that we have barely got off the earth's surface and our best telescopes cannot resolve planets beyond a colored dot or a wobble of a star. As for us not detecting any life forms in our little bit of space around us there are a myriad of reasons why that could be true

-we could be the lifeforms seeded from somewhere else
-we cannot detect them because they are so advanced
-we don't know what to look for
-we don't accept they exist even though we they have been seen
-we are in a backwater area that doesn't get visited very often
-intelligent life is spread out thinly or is concentrated rather than dispersed

Using the word 'paradox' is too strong.

syklops

Im not that impressed with the article, or with Fermi's Paradox. He assumes that the current age of the Universe ~5.6Bn years is ample time for numerous civilizations to exist far more advanced than us. Why does he assume that? Why is that such an easy assumption to make?

We are the most advanced civilization we know about, and we cant get as far as Mars not a mind conquer plant our flag on Centauri Alpha. Why should we assume that another civilization, given the same amount of time as us would develop faster or to a greater extent than we have? That seems to me to be the main hole in his paradox.

His comment, "So what Fermi immediately realized was that the aliens have had more than enough time to pepper the Galaxy with their presence. But looking around, he didn't see any clear indication that they're out and about.", seems just daft to me. 60 years ago, and even today our knowledge of the Universe is so minor that saying he looked around the Universe and saw no evidence of other civilisations, is akin to peering in the front door of Tesco and saying "From what I can see, they dont sell food".

maninasia

Taking the idea that life on Earth is a spontaneous result of evolutionary processes (or indeed of seeding) then it is very reasonable to assume that are countless other civilisations out there. It's a numbers game, if the universe is infinite it will produce an infinite number of civilisations.

You can also look at is a few other ways like you said. Life on earth could have jumped off 100 millions years earlier if dinosaurs had bigger brains and hands perhaps? Or maybe it could have been destroyed in numerous extinction events and we have just been incredibly fortunate. But indeed the supposed reason for the rise of mammals was one of these cataclysimic events.

Simply put we are working off a limited knowledge of science and of our own history.

One thing I have to say though is that if life evolves to live in space what's going to stop it moving around and evolving further. Just like the unicellular precursor to all life on Earth?

Rubecula

If we consider or think that our radio waves are communicating with other civilisations, then those civilisations would need to be within a 70 light year radius of us. And that is supposing that such civilisations would collect and understand our signals. It is a pretty small sphere in the scale of the galaxy let alone the universe. Then think how close we have been to annihilation of ourselves.

I suppose it is possible tht there is a civilisation out there we can contact and even communicate with, but even if there are millions of them, it is very unlikely IMO, simply due to our time as a technological society and the sheer size of time and space.