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Path: utzoo!watmath!clyde!floyd!cmcl2!lanl-a!jlg
From: jlg@lanl-a.UUCP
Newsgroups: net.space
Subject: Re: Lunar artillery
Message-ID: <4807@lanl-a.UUCP>
Date: Fri, 6-Apr-84 19:54:44 EST
Article-I.D.: lanl-a.4807
Posted: Fri Apr  6 19:54:44 1984
Date-Received: Sat, 7-Apr-84 05:08:29 EST
References: <509@sri-arpa.UUCP>
Organization: Los Alamos National Laboratory
Lines: 9

Even if the shells were fired parallel to the ground (this able to orbit), they
still wouldn't come back to launch point (not for a long while anyway).  The
reason is that the moon turns under the orbiting projectile.  If you have
ever watched the ground track projections of LEO vehicles, you will have 
noticed that the orbit seem to precess around the planet.  The only way 
to avoid this is to have an orbital period that is an integral multiple 
(or divisor) of the planets rotation period.  A surface orbit of the moon
does not meet this requirement.  (Well, maybe they were on the lunar equator
firing exactly east or west!)