On Sun, 28 Jun 2009 17:14:14 +1000, "Peter Webb"
wrote:

Furthermore, the radiation from a reflected area is isotropic - goes in all
directions - and hence very little is directed towards the earth.

Actually, it is lambertian in its distribution, and it would have a
major lobe that was directed in rather typical fashion (at the same,
but negative angle to the norm to the surface). However, as is the
intent of your response, very much less will find its way to the
intended target.

73's
Richard Clark, KB7QHC