Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10 beta 3/9/83; site sdcrdcf.UUCP Path: utzoo!watmath!clyde!burl!hou3c!hocda!houxm!houxz!vax135!floyd!harpo!decvax!ittvax!dcdwest!sdcsvax!sdcrdcf!darrelj From: darrelj@sdcrdcf.UUCP Newsgroups: net.games.trivia Subject: Re: heavenly bodies (lunar rotation) Message-ID: <1130@sdcrdcf.UUCP> Date: Tue, 12-Jun-84 08:36:34 EDT Article-I.D.: sdcrdcf.1130 Posted: Tue Jun 12 08:36:34 1984 Date-Received: Thu, 14-Jun-84 00:45:54 EDT References: <99@tekigm.UUCP> <7975@watmath.UUCP> <796@pyuxa.UUCP> <271@hou2g.UUCP> Reply-To: darrelj@sdcrdcf.UUCP (Darrel VanBuer) Organization: System Development Corporation, Santa Monica Lines: 18 The moon does rotate with a motion which is distinct from its revolution about the earth. (However the two motions are phase-locked by tidal forces so they have the same period) This independent (and essentially constant speed to conserve angular momementum) rotation can seen because the eliptical orbital path of the moon (about 10%) changes it's speed around Earth, so the rotation gets a little ahead of and behind keeping one face toward Earth--thus we have earth based photos of about 55% of lunar surface. If you want to have the moon wind up a rope, run your rope to Mars. Earth is not sufficently decoupled from the moon to be a suitable reference point. -- Darrel J. Van Buer, PhD System Development Corp. 2500 Colorado Ave Santa Monica, CA 90406 (213)820-4111 x5449 ...{allegra,burdvax,cbosgd,hplabs,ihnp4,sdccsu3,trw-unix}!sdcrdcf!darrelj VANBUER@USC-ECL.ARPA