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Re: starship-design: It's a bad, bad world out there
David Levine wrote:
> Is this necessarily true?
> How far away could we detect radio transmissions?
> The idea behind this part of the sci.astronomy FAQ is that detection of
> normal radio and television signals at interstellar distances is a myth.
> Math is included. One summary quote:
> "Even a 3000 meter diameter Radio Telescope could not detect the 'I Love
> Lucy' TV show (re-runs) at a distance of 0.01 Light-Years!"
Yes, it is true. Unfortunately they can't hear TV shows without BIG
radio arrays. Or is that fortunate...?
> Narrowband radar is apparently much easier to detect, but will be short
> in duration and non-repeating.
Like things such as the WOW signal, 34 META I signals, BETA signals...
All I might add on the galactic plane. I have a paper by Carl Sagan on
my computer. I'll email it to people by request, as its too big for the
SSD mailing list. Limit was 40K I believe?
> I don't know how easy to detect the EM leakage of a power-grid would be,
> but it doesn't sound likely.
Well, that depends on what kind of power grid you're speaking of. Low
tech would be virtually undetectible. Mid level, like us VERY
detectible. High tech may be either blaringly loud, or more likely very
silent. Or it could account for some of the IR emmisions we've detected
around F, G, K class stars. Perhaps one reason they're not here is they
are like us: "If it don't repeat, it don't matter anyways." Maybe we
should document these signals and see if a pattern emerges.
My two cents.