Kepler's three laws of planetary motion
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enHow long is a day?
https://plus.maths.org/content/how-long-day
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Nicholas Mee </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="https://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="https://plus.maths.org/content/how-long-day" target="_blank">read more</a></p>https://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 https://plus.maths.org/contentCareer interview: Systems engineer
https://plus.maths.org/content/career-interview-systems-engineer
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Marianne Freiberger </div>
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<div class="pub_date">September 2008</div>
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<div style="position: relative; left: 50%; width: 70%"><font size="2"><i>Back to the <a href="https://plus.maths.org/content/ingenious-constructing-our-lives">Constructing our lives package</a></i></font></div><br clear="all">
<p><i>A version of this interview is also available as a <a href="/podcasts/PlusCareersPodcastSep08.mp3">podcast</a>.</i></p><p><a href="https://plus.maths.org/content/career-interview-systems-engineer" target="_blank">read more</a></p>https://plus.maths.org/content/career-interview-systems-engineer#comments48aerodynamicscareer interviewdifferential equationellipseengineeringheat diffusion equationKepler's three laws of planetary motionmathematical modellingpartial differential equationphysicssatelliteScience & Engineeringspace explorationstatisticsuncertaintySun, 31 Aug 2008 23:00:00 +0000plusadmin2437 at https://plus.maths.org/contentEditorial
https://plus.maths.org/content/pluschat-20
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<p>Plus 1000 — Mathematical lives</p>
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<div class="pub_date">September 2007</div>
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<h2><i>Plus</i> 1000 — Mathematical lives</h2>
<p>To celebrate the tenth anniversary year of <i>Plus</i>, we've been running a series on our favourite maths in history.<p><a href="https://plus.maths.org/content/pluschat-20" target="_blank">read more</a></p>44astronomybernoullibernoulli equationbernoulli numbercalculuscomputer programmingcomputer sciencecopernicuseditorialgalileogroup theoryhistory of mathematicskeplerKepler's three laws of planetary motionleibnizNewtonnoether's theoremplus birthdayst. petersburg paradoxwomen in mathematicsFri, 31 Aug 2007 23:00:00 +0000plusadmin4900 at https://plus.maths.org/contentMission to Mars
https://plus.maths.org/content/mission-mars
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The geometry says that now is the right time for a mission to Mars. </div>
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<div class="pub_date">16/06/2003</div>
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<p>The race for Mars is on. The European Space Agency's <a href="http://www.esa.int/SPECIALS/Mars_Express/index.html">Mars Express</a> mission and the first of two US <a href="http://mars.jpl.nasa.gov/mer/">Mars Exploration Rovers</a> launched by NASA are currently hurtling toward the red planet, each hunting for water and possible signs of life. But why this flurry of activity? Is it simply the
spirit of competition that has driven the parallel missions?</p><p><a href="https://plus.maths.org/content/mission-mars" target="_blank">read more</a></p>https://plus.maths.org/content/mission-mars#commentsaphelionellipseEuropean Space AgencykeplerKepler's three laws of planetary motionMarsNASANewtonorbitperihelionSun, 15 Jun 2003 23:00:00 +0000plusadmin2717 at https://plus.maths.org/contentThe origins of proof II : Kepler's proofs
https://plus.maths.org/content/origins-proof-ii-keplers-proofs
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J.V. Field </div>
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Johannes Kepler (1571-1630) is now chiefly remembered as a mathematical astronomer who discovered three laws that describe the motion of the planets. <b>J.V. Field</b> continues our series on the origins of proof with an examination of Kepler's astronomy. </div>
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<div class="pub_date">May 1999</div>
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<p>As we explained in <a href="/issue7/features/proof1/index.html">The Origins of Proof, Part I</a> in <a href="https://plus.maths.org/content/issue/7">Issue 7</a> of PASS Maths, the concept of a "proof" was developed in the field of geometry by the Greeks. The Pythagoreans and Euclid were among the mathematicians who developed the idea of abstract deduction. But during the Renaissance the philosophy
of nature increasingly came to rely upon mathematics to help to explain the Universe and its workings.</p><p><a href="https://plus.maths.org/content/origins-proof-ii-keplers-proofs" target="_blank">read more</a></p>https://plus.maths.org/content/origins-proof-ii-keplers-proofs#comments8astronomyellipseerrorgeometrygravityhistory of mathematicsKepler's three laws of planetary motionproofFri, 30 Apr 1999 23:00:00 +0000plusadmin2389 at https://plus.maths.org/content