Quote Originally Posted by Syme View Post
I know none of us here are scientists
uuuuuuuummmm excuse me said the phd student waiting for the vacuum chamber to pump down so he can do e-beam lithography?

i mean i completely admit to being the worst graduate student in the world, but still...

(ps please don't tell the people who will be on my thesis defense committee i said that kthnx)

and no i'm not an exobiologist either. exobiology is hillarious: it's the only field of "science" whose object of study hasn't been proven to exist (well, exobiology and string theory, though string theory doesn't have any "experimental string theorists.")

Also of related interest is the Drake Equation (http://en.wikipedia.org/wiki/Drake_equation), a mathematical formula used to guesstimate the number of communicating civilizations in the Milky Way galaxy at any one moment. This equation has been called meaningless, but it was never supposed to actually "tell us" how many such civilizations exist or to yield a certain predictively correct result. Anyone who likes can plug in their own values, at least some of which are necessarily pulled out of thin air, and see what result they get.
yeah, the problem people who don't understand science think it's suppose to be predictive, people like reporters and those who listen to them. i remember having a long argument with a person about how some of those factors, like the chance for a planet that can develop life to actually develop life, are completely unknown. they still didn't believe me afterwards and were convinced that the drake equation was something more than a device to spur thought and discussion.

Quote Originally Posted by sailor jack View Post
Alien life is certainly more than likely in some form and I believe that some intelligent lifeforms may exist. As one of the sections of the Fermi paradox wiki page states, scale is a huge factor in any communication between the two. The Aricebo Message was only sent out in 1974 and will take 25000 years to reach its intended destination. A reply will take some time after that, depending on the level of technology of the recipients to send a reply, and that is only after they have decoded the message and figured out where it has come from. The level of alien technology is very important as it can either be too adanced for them or not advanced enough (imagine people in 300 years time trying to play a VHS, there is a possibility that such "primitve" technology may have been totally lost). If we do get a reply, it will have been a very lucky shot with a massive coincidence in the technology the respective communicators have.

However if we consider ourselves as the aliens in the view of other beings, if we were to recieve a message first (which i think is the most likely situation) and if we were able to decode it, even with what is considered a highly advanced level of technology, we would not be able to go and visit for a very long time, probably not without the help of the group that contacted us anyway. Even the idea that we would be able to reply is questionable.
first of all, we have been transmitting radio signals to space for the last 90 to 100 years. that's how long we've had radio communications used on a moderately large scale (thought the first signals were wireless telegrams and not audio signals). so we've sent out radio waves out to a distance of 90 or 100 light years. still, that only covers something on the order of 10^4 stars (i think) out of the 200 to 600 billion stars in our galaxy.

also, all that matters is that we find a radio signal with structure. it doesn't matter if we or the hypothetical aliens can decode it. in fact, when radio signals from pulsars were first detected, people thought they might be radio signals from an alien civilization. it turned out that it was just a magnetic rotating remnant of a star that went supernova which appears from earth to send out pulses of electromagnetic radiation periodically (it's actually a "beam" of EM radiation that rotates like the light in a lighthouse, so we can see it when it's facing earth).

there are a number of reasons that i could think of as to why we haven't heard anything from other intelligent life, if indeed there is life in elsewhere in our galaxy. i have to go, so i'll post them in a few.