SpaceTiger,
Would the Earth break orbit the instant the sun disappears or would it continue to orbit normally for another 8 minutes before breaking off at a tangent?
I guess if gravity propagates at the speed of light then it would have to be the latter but it doesn't make intuitive sense to...
Good point, I understood the OP to be - if we got wiped out tomorrow what are the chances somebody else would step up to the plate and get to approximately where we are today.
I am a machine so I'd have to say 'yes' here.
I don't understand why you don't understand why I don't understand...
I think that a technologically advanced and organized civilization is usually what we are talking about when speak of intelligent life. It is just a lot easier to use the word intelligent. While a dolphin holding a sponge to avoid getting stung may be quite cute the conversation one can have...
Turbo-1,
While, the nuclear winter that article describes is certainly horrible, I'm not convinced that such a disaster would wipe out humanity. It makes a comparison to the Cretaceous extinction which wiped out 75% of species. That means that 25% of species survived. Many mammals...
why 1000 year window?
I was following you until here.
Are you saying that radio becomes obsolete after 1000 years? If so wouldn't some alien races still try to say hi using radio? Especially if they new we were here? Aren't we within 100 years or so of being able to see other Earths in...
confused
I'm not sure I understand your assumptions. Are you saying that all these high level civilizations stopped broadcasting as soon as we had the technology to here them? Or are you saying that all of these advanced civilizations developped radio technology at the exact same time that...
Another amateur question
let us suppose that we are exactly at the centre of a spherical universe
if we look in one direction and see stars, microwaves or whatever for 6.85 billion light years then nothing
then we turn around and look in the opposite direction and see stuff for 6.85 billion...