Re: Corner Cubes on EGP satellite

William Leininger (
Wed, 6 Dec 1995 14:52:18 -0600

John Marchant said:
>Don't know what else EGP has on it, but if it's an uncontrolled
>sphere studded with corner cube reflectors and nothing else, then its
>primary purpose is to act as a reflector for laser ranging. There are
>a few dozen of these sites around the world, using satellites like
>EGP and others (e.g. ERS-1, fitted with a few reflectors on the
>side. The data's used for research into the upper atmosphere, tectonic
>shift, etc.

Actually, EGP is more wonderful than that.  In my experience, corner cubes
don't look like much to the binocular aided eye.

EGP is a six foot diameter sphere, and the parts of the surface that don't
have corner cubes are covered with flat mirrors!

A marvelous satellite to look at, and the only one that I could identify by
sight when it unexpectedly crossed my field of view during an observing
session a few years ago.

(And, yes, it is listed as a Geodetic satellite.)

Bill L.

William H. Leininger                     | Ph: (708) 797-8871
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