David Gould

With regard to aliens being here now, I think that the circumstantial evidence against it is far greater than any evidence for it.

If we assume that we were not created by aliens then:

For an alien race to choose randomly to come here without knowing in advance that there was intelligent life here, given the incredible number of options available to them, is unthinkable.

The only way they could know that we were here is the detection of radio signals, which only travel at the speed of light. As far as I am aware, the first radio transmissions to have the strength to get through the Van Allen belt was Hitler's Nuremburg speech some time in the 30s.

If we assume it was 1930 (can't be bothered looking up the exact date) then 72 years have passed.

For aliens to be here, assuming they can travel at the speed of light, they would have to have been within 36 light years of Earth and have set of instantly. When you start out with the more realistic assumption that they can travel at 10% of the speed of light and need a few years to prepare for a major expedition of this sort then 7 light years becomes the upper limit.

There is not that much within 7 light years of Earth.

My contention is that the only way aliens could be here now is if they seeded us and left a device to monitor us and signal that back to them. Thus, the could be a long way away and yet plan to set out when we discover gun powder, for example.

GunnerJ

Look, marduk, I'll tell you right now that I'm agnostic towards the UFOs are aliens explaination. I'd be willing to state that it's possible they are. But I'd also be willing to state that it's possible the god of deism exists, I'm just not persuaded by the evidence to positively state that it does. Same with ETC hypothesis. There are also some logical problems with the explaination, mostly about motivations and technology, and the quality of evidence. I wouldn't ridicule someone for saying they think aliens might be here already, but I'd think they're a little wacky if they have no good reason to think so. That's all.

Jayhawker Soule

Well, at the very least, I appreciate your honesty.

Jayhawker Soule

Out of curiosity, are you also agnostic about ESP and Ghosts?

GunnerJ

Yes. But the level of my outright skepticism depends on how one defines a "Ghost" or an extra sensory preception.

Jayhawker Soule

Thanks for responding.

Marduk

Dave said:

"The only way they could know that we were here is the detection of radio signals, which only travel at the speed of light. As far as I am aware, the first radio transmissions to have the strength to get through the Van Allen belt was Hitler's Nuremburg speech some time in the 30s."

Unless they have a telescope array similar to the one NASA wants to launch in a few years, that can see smaller planets around stars, they blot out the light from the star. They could have picked out planets with high life potential to investigate.
Till all stars within a 1000 light year radius of Earth have been checked for life possible planets and they all come up nil I will remain open to the possibility that some UFO's are of extraterrestrial origin.

David Gould

That is true.

However, 1,000 years at 10% of the speed of light would mean that for them to be here now they would have had to see something of interest 11,000 years ago. (1,000 years for the light to reach them, 10,000 years of travel time).

Not too much evidence for an intelligent species at that point in Earth's history that could be seen with a telescope...

And I am 'open to the possibility' also. It just seems to me that there is no evidence in favour of it and lots of evidence against it.

Think of it this way: if the aliens wanted to hide from us, they could (given the technological difference between us - they have interstellar travel and we do not.) Why then do they keep leaving evidence (people can see them, people remember being abducted et cetera)?

Either it means they are incompetent at hiding, they do not realise that we are intelligent (in which case why do they seem to be sneaking around like a bumbling burglar?) or they are trying to talk to us but are too incompetent to work out how to do it.

We can not possibly be a threat to them at this stage in our history.

There is no reason for them to hide unless they do not want to alarm us. And yet, they are failing to hide from many people, demonstrating stupidity on a grand scale.

The scenarios to me seem as logical possible as the existence of the Christian God. I admit however that the apologists for UFOs have a 'mysterious ways' defence that is better than Christianity's...

Marduk

"There is no reason for them to hide unless they do not want to alarm us. And yet, they are failing to hide from many people, demonstrating stupidity on a grand scale."

Let's not get into their possible motives, (my favourite is that they are concerned about us in the same manner a farmer is concerned with his herd) this could go on forever. Hard enough to make even the possibility of their existence seem plausible to some.

cricket

If intelligent life is so close-in that they can visit, why is it we've never heard theirradio waves?