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arXiv · 1207.0982

Measuring the eccentricity of the Earth orbit with a nail and a piece of plywood

Thierry Lahaye
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Abstract

I describe how to obtain a rather good experimental determination of the eccentricity of the Earth orbit, as well as the obliquity of the Earth rotation axis, by measuring, over the course of a year, the elevation of the Sun as a function of time during a day. With a very simple "instrument" consisting of an elementary sundial, first-year students can carry out an appealing measurement programme, learn important concepts in experimental physics, see concrete applications of kinematics and changes of reference frames, and benefit from a hands-on introduction to astronomy.

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Thierry Lahaye. 2012-07-04. Measuring the eccentricity of the Earth orbit with a nail and a piece of plywood. https://doi.org/10.1088/0143-0807%2F33%2F5%2F1167

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