Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 (Tek) 9/28/84 based on 9/17/84; site vice.UUCP Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!mhuxt!houxm!mtuxo!mtunh!mtung!mtunf!ariel!vax135!cornell!uw-beaver!tektronix!tekcrl!vice!keithl From: keithl@vice.UUCP (Keith Lofstrom) Newsgroups: net.space Subject: Re: Antigravity References Message-ID: <126@vice.UUCP> Date: Fri, 28-Jun-85 20:01:52 EDT Article-I.D.: vice.126 Posted: Fri Jun 28 20:01:52 1985 Date-Received: Wed, 3-Jul-85 08:34:43 EDT References: <2295@mordor.UUCP> Organization: Tektronix, Beaverton OR Lines: 31 In article <2295@mordor.UUCP>, jennings@AEROSPACE.ARPA mentions a gravitational oscillation "with a period of 24 hours, 50 minutes with a magnitude of 10e-6g". The author of the paper he cites suggested a new theory of gravity was needed. The period mentioned just happens to be the time the Earth takes to make one revolution RELATIVE TO THE MOON. Hmmm...perhaps he made this "Earth-shaking" discovery in a lab without windows... Gravitational fields are inverse square, and gravitational gradients are equal to the derivative of this field. This means that the lunar gravitational effect is a little stronger on the near side of the Earth than on the far side or at the center. That's the source of tides. Computationally, the size of the effect at the equator is only 1.1e-7g. This assumes a rigid Earth and no gravitational effects from tidally shifting oceans and atmosphere, though. Any astronomers care to pick up the ball (wait 'til after moonrise; it's easier then :-), and do a better calculation? Newtonianly yours; -- Keith Lofstrom MS 59-316, Tektronix, PO 500, Beaverton OR 97077 (503)-627-4052 uucp: {ucbvax,decvax,chico,pur-ee,cbosg,ihnss}!tektronix!vice!keithl CSnet: keithl@tek ARPAnet:keithl.tek@rand-relay