analemma
http://plus.maths.org/content/category/tags/analemma
enHow long is a day?
http://plus.maths.org/content/how-long-day
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Nicholas Mee </div>
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<img class="imagefield imagefield-field_abs_img" width="100" height="100" alt="" src="http://plus.maths.org/content/sites/plus.maths.org/files/issue53/features/mee/icon.jpg?1259625600" /> </div>
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The obvious answer is 24 hours, but, as <b>Nicholas Mee</b> discovers, that would be far too simple. In fact, the length of a day varies throughout the year. If you plot the position of the Sun in the sky at the same time every day, you get a strange figure of eight which has provided one artist with a source for inspiration. </div>
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<div class="pub_date">December 2009</div>
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<p><i>This article was part of a <A href="http://plus.maths.org/content/seven-things-everyone-wants-know-about-universe">project</a> we ran to celebrate the <a href="http://www.astronomy2009.co.uk/">International Year of Astronomy 2009</a>. The project asked you to nominate the questions about the Universe you'd most like to have answered, and this is one of them. We took it to the physicist <a href="http://www.nicholasmee.com">Nicholas Mee</a> and here is his answer.</i></p><p><a href="http://plus.maths.org/content/how-long-day" target="_blank">read more</a></p>http://plus.maths.org/content/how-long-day#comments53analemmaastronomygeometryinternational year of astronomy 2009Kepler's three laws of planetary motionTue, 01 Dec 2009 00:00:00 +0000plusadmin2374 at http://plus.maths.org/content