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Analemma Calendar for 2008
The analemma is a term in astronomy used to describe the plot of the different positions of the Sun on the sky recorded at the same time of day and from the same location, each day through the calendar year. This analemma photo is a composite of 364 images of the Sun, made every day at three times of the day (8 a.m., noon and 2:30 p.m.) from Cascade, CO. Prepared during 2004 and 2005. The shape, resembling the figure 8, comes from the fact, that Earth's orbit is an ellipse, and therefore Earth's speed is not constant. Close to the Sun it moves faster. For the explanation, see the Analemma's page (she is a mathematician). A more thoroughtful mathematical explanation of the shape you may find on Mad Teddy's page and more detail on its shape on the equator is here. The Moon analemma is less symmetrical (it's a barely figure 8) because the Moon's ellipse is more elongated (5.5% eccentricity versus Earth's 1.7%). Even more 'squashed' ellipse (eccentricity 9.3%) is the Mars trajectory around the Sun, so that the fig. 8 disappears and rather resembles a tear drop. The calendar labeling is for the year of 2008, it shows weekends as colored dots. The 24x36 inch poster (made on glossy Fujicolor Crystal Archive Paper) is $47. Feel the Sun position every day, throughout the year. Analemma clearly explains why the earliest (latest) sunset is not at the winter (summer) solstice day. This unique calendar is really not only for astronomy fans, but it is a cool gift for everybody sensitive to passing seasons and time. Just send me an e-mail to order it or for more info.
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Size of the original: 3674x5505
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