A Kepler's note on secular inequalities

Antonio Giorgilli

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arXiv · 1402.4439

A Kepler's note on secular inequalities

Antonio Giorgilli

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Abstract

I discuss the problem of secular inequalities in Kepler by giving account of a manuscript note that has not been published until 1860. In his note Kepler points out the need for a model, clearly inspired by the method of epicycles, that describes the secular inequalities as periodic ones. I bring attention to this point, that seems to have been underestimated, since the references to Kepler's work usually report only that he observed a decreasing mean motion for Saturn and an increasing one for Jupiter.

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Antonio Giorgilli. 2014-02-13. A Kepler's note on secular inequalities. https://arxiv.org/abs/1402.4439

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