NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Navigating Around Hills and Dips in the Ocean
From: George Istok
Date: 2003 Aug 16, 22:31 -0500
From: George Istok
Date: 2003 Aug 16, 22:31 -0500
Mr. Huxtable, Though I am now in agreement with you, I came to that position by a slightly different argument (that may or may not be valid). I assumed a completely isolated sphere of a light matter covered with water, a distance from the center of the sphere to the surface of the water, a value (G) for the gravitational attraction at the surface of the water, and that the surface of the water at any point must always be at a distance from the center of the sphere such that the value of G is constant. I then introduced a much smaller sphere made of a dense matter into the original sphere so that the smaller sphere does not encompass the center of the larger sphere. The center of gravitational attraction of these combined bodies is somewhere on a line between their two centers. Since, at this instant, the shape of the original sphere and distribution of water covering the sphere has not changed, then, at the surface of the water "above" the small sphere, the value of the gravitational attraction is not G but something larger. Thus the water must move away from the center of the original sphere until the gravitational attraction is again G. That is, a "mound" of water appears. I do not claim that the argument above is whole or that it is valid, but it did convince me that there will be a mound over an anomaly where the attraction is stronger and a dip where it is weaker. Your argument is much simpler and even more convincing. George Istok