Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site mit-eddie.UUCP Path: utzoo!watmath!clyde!burl!ulysses!mhuxl!ihnp4!mit-eddie!barmar From: barmar@mit-eddie.UUCP (Barry Margolin) Newsgroups: net.games.trivia Subject: Re: more on the moon debate Message-ID: <2104@mit-eddie.UUCP> Date: Mon, 11-Jun-84 22:42:53 EDT Article-I.D.: mit-eddi.2104 Posted: Mon Jun 11 22:42:53 1984 Date-Received: Tue, 12-Jun-84 23:47:39 EDT References: <1369@decwrl.UUCP> Reply-To: barmar@mit-eddie.UUCP (Barry Margolin) Organization: MIT, Cambridge, MA Lines: 12 The fact that the moon always keeps the same face to the earth is no coincidence. It is the result of a couple of billions of years of tidal forces. No planet or satellite is perfectly circular, and after billions of years the forces on the uneven portions add up and the revolution speed slows down and the size of the orbit decays. I seem to recall that Asimov devoted one or two of his "Fantasy & Science Fiction" Science columns to this subject several years ago; check in the anthologies of his articles. -- Barry Margolin ARPA: barmar@MIT-Multics UUCP: ..!genrad!mit-eddie!barmar