Michael Foster <mf...@yahoo.com> wrote:
> Everyone just assumes that these visitors must be from civilizations far > advanced from our own. That may or may not be true. > If they are actually visitors from other civilizations, they have to be far advanced. They cannot be from anywhere in the solar system. Our robot probes have now visited every planet and most large moons. There is no sign of intelligent life anywhere in the solar system. So if there are non-human visitors they must have crossed interstellar space. To do that, they have to be far advanced over us. We could not begin to do that, except -- as I noted -- with tiny spacecraft that cannot be controlled when they arrive.
