Newsweek Confuses Broadcasting and Cable TV
Sat Oct 24 21:27:09 EDT 2009
> They are uplinked to a satellite, and I'm sure some (most?) of the signal
> misses the bird and goes furter off into the heavens.
For practical purposes, 100% of the signal from an earth station goes off
into the heavens. And it goes on a direct path and with far less
interference than emanations from the TV stations, which rarely have much of
a vertical component at all.
As for receivability from far off, sorry to rain on the parade.
Each signal will show up very briefly, once every 24 Earth hours. It's very
doubtful that an intelligent being would get anything useful from that,
other than the fact that we're out here.
Once you get away from the geostationary orbit, which is very close to the
surface of the plant in astronomical terms, it takes a lot of energy to stay
sync'ed with the surface of the earth. But that is what it would take to get
a usable signal for the duration of even a single show. Not too far out,
you'd have to be travelling nearly at the speed of light and offsetting
various gravitational influences.
So the idea of folks on planets 60 light years away watching "I Love Lucy"
reruns is a nice concept, but utterly out of the question unless they send a
robot here to capture them somehow and beam them back. Assuming they
respond instantly and the robot travels at the speed of light, they won't
see any programs for another 120 years.
More information about the Boston-Radio-Interest