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In the context of explaining the elliptical motions of the planets, this figure illustrates the method of constructing an ellipse using a piece of string. This in turn depends upon the mathematics of the ellipse: the distance from one focus to any point on the ellipse, plus the distance from that same point to the other focus (plus, if you wish, the distance between the foci, which is constant) is constant.
All portions of this document not noted otherwise are Copyright © 2007 by David M. MacMillan and Rollande Krandall.
Circuitous Root is a Registered Trademark of David M. MacMillan and Rollande Krandall.
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