Scale of the universe - awesome widget.

[JJMcClure]

http://scaleofuniverse.com/ - this is very cool, check it out.

[Clinton]

I gave this link to my son .... he spent hours on that page!

[JJMcClure]

I gave this link to my son .... he spent hours on that page!

Cool

Does he have a particular interest that it facillitated?

[Clinton]

He likes numbers and devours anything maths related. He's also pretty good at maths, when he was in school they had to make special provision for him. Like most boys he also has this fascination for space and for amazing facts. All those interests come together on this site, it's marvellous!

[Kay]

Amazing! Thanks. It kinda reminds us of perspective. When you look at the big picture we're not even as big as the smallest ant or grain of sand. But I do believe we'll get out and explore a bit more. I know that Star Trek is fiction but I believe that sort of thing could be a reality one of those days. (Not a stupid fat git like Shatner shagging dolly birds, but teams of people going out to explore other planets.)

There just has to be life out there somewhere. We can't be the only ones. Can we?

[TheodoreK]

Maybe life is too rare and far apart or maybe we are just the first ones for all we know! The Fermi paradox has been boggling my mind since I was a kid watching science documentaries. (I still do!)

If we are indeed alone or if our closest neighbors live millions of light-years away then respect for all kinds of life (and procreation for that matter) suddenly becomes even more significant to us and for all we know there is no evidence to the contrary.

So make love not war!

[JJMcClure]

! The Fermi paradox has been boggling my mind since I was a kid watching science documentaries. (I still do!)

Now you're on a subject that I just love to discuss. I totally get why there's been time for intelligence to emerge, in many places over vast lengths of time, to become starfaring and to sweep back and forth across this galaxy, wave upon wave of life expanding and contracting, using up resources, leaving their mark, and yet when we look out there we see no evidence of it, hence the paradox. How can we possibly be alone, and yet we seem to be?

What if though, we look out there, imagining what we see to be pristine and untouched and yet it's actually not. There are huge expanses of our galaxy where there are no stars and there should be many, where stars should have planets but don't, where there are stars that should still be in their main sequence but are oddly aged or even gone Nova, even the asteroid belt in our own solar system may once have been a planet but what happened to it? What we're seeing may actually be the evidence and we just don't recognise it for what it is, the evidence of colonisation and interspecies conflicts on a scale we can barely imagine and over lengths of time that make the time we've been around and looking out there as tiny a fraction of a split second as you can imagine?

We could be seeing evidence of engineering on a cosmic scale and not recognise it for what it is.

[Chabrenas]

We could be seeing evidence of engineering on a cosmic scale and not recognise it for what it is.

Yes, I agree that lack of imagination could be the real problem. At these scales, very few people are even remotely numerate. The formulae that are bandied about were developed by very competent mathematicians, but we're randomly prodding with a needle here and there looking for evidence we don't know how to describe, within domains our brains can't map without multiple simplifications - each of which could easily eliminate the very evidence we're looking for.

[JJMcClure]

but we're randomly prodding with a needle here and there looking for evidence we don't know how to describe

And that's just within the context of life as we can understand it, carbon based life that needs liquid water and a certain temperature range and a certain period of planetary stability to evolve etc etc etc....

How does Fermi account for the fact we might be seeing the supposedly missing evidence and just not recognise what we're seeing?

(I'm playing devil's advocate to some extent here, if this galaxy had been populated as often as the maths suggest it should have been, there really shouldn't be many resources left in our solar system but most mineral resources on our own panet are still right there on the surface waiting for us to use them,as if they'd never been touched before.)

[TheodoreK]

How does Fermi account for the fact we might be seeing the supposedly missing evidence and just not recognise what we're seeing?

I struggled for a while, trying to find a way to reply to this question without ending up misunderstood, especially since I agree with almost all the other points made by JJ and Chabrenas.

I prepared a long post arguing about facts vs possibilities, skepticism and the scientific method and how not recognising a phenomenon does not increase the possibility of said phenomenon existing in any way (that also goes well with Clinton's Invisible Pink Unicorn from that other thread, by the way )

However, in the end I think my ideas are epitomized perfectly in two sentences by Carl Sagan from his book "The Demon-Haunted World: Science as a Candle in the Dark".

So I will just quote the great astrophysicist and spare you my long-winded and much less elegant post.

If any powers whatever may be ascribed to the aliens—because their technology is so advanced—then we can account for any discrepancy, inconsistency, or implausibility. ...
...Such "explanations" can explain anything, and therefore in fact nothing.