starship-design: Extraterrestrials

["Kyle R. Mcallister" <stk@sunherald.infi.net>]

Greetings all:

I've heard many things about ET's mentioned here, and wish to add to this:

Why is it always assumed that they would want to contact us? We have only sent one intentional signal to 'them'. Why would they be interested in us? If they are less advanced, they wouldn't know about us. If they are as advanced, but as Carl Sagan speculated, 200 light years away, they still might not have heard from us if we didn't send a directed signal, and vice versa. If they are more advanced, they might not care about a lowly civilization like us. If they use a different form of communication across the stars than radio, we wouldn't have heard from them. (BTW: My speculation that advanced civilizations would be indifferent to us was called 'too anthromorphic', while advanced civ's blowing up the planet was called 'likely'. Forgive me, but isn't warfare a very human characteristic? Its pointless to say 'this is how it is'. We can only speculate;) 

Also: 
How do we know that we HAVEN'T heard a signal from intelligent extraterrestrial civilization? I have been keeping up with what SETI is up to, and found some very interesting things:
1. If they didn't send a directed signal, the chances of a strong, continuous signal are nearly nil. (Unless they're at Alpha Centauri).
2. Nondirectional signals similar to radar would be detected as faint, brief whispers from space. (If they were close enough)
3. META detected over 300 signals that have the earmarks of being from an ETI. About 20% repeated at the same frequency and position in the sky at least once.
4. Hypothetical advanced transmission systems might not use methods currently known to us. (imagine trying to send a radio message to Leonardo Divinci)
5. Hypothetical superluminal transmission systems would almost certainly be undetectable with current equipment. If these exist, they would certainly be the choice method of interstellar communications.

Best Regards,
Kyle Randall Mcallister
Email: stk@sunherald.infi.net
Phone: 228-875-0629
Fax: 228-872-5837