I wrote:
> In one of his books, Arthur Clarke suggested deploying a bunch of sensors > orbiting the sun, and then setting off a gigantic neutron bomb on the other > side of the sun (away from Earth and other populated planets) to make > something like an instantaneous x-ray of the solar system . . . > I guess it was a bomb tuned to make gamma rays. It made what you might call a gigantic radar picture, rather than an x-ray. I don't recall which book that was in. Radar was one of Arthur's favorite things, since that's what he did professionally. As I recall, it turned into what a programmer would call a "Hello World!" test. A century later an extraterrestrial civilization responds. I have heard that according to recent analyses, radio and television broadcasts cannot be detected after a few light years. So the scenario portrayed in the Carl Sagan's "Contact" is impossible. That's a pity. - Jed
