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How does the analemma relate to the motion of the sun along the ecliptic?

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Answer:

The sun is always on the ecliptic, even though the analemma seems to suggest that the sun is engaged in some kind of fancy wobble. The analemma appears because civil time, or Universal Time (UTC) does not line up perfectly with solar time. So the analemma captures the sun sometimes earlier than, and sometimes later than, what would be the theoretical 'average' position of the sun (sometimes called "mean sun") over the course of a year. There is a reason that standard time used to be called Greenwich Mean Time. UTC gives the average day over the course of a year, independent of the exact position of the sun.

The analemma doesn't actually 'exist' as a physical reality. For those who are not familiar with the term, this is how you would 'observe' the analemma. Set up a camera in such a way that it will capture an image of the sun at exactly 12:00 UTC. Keep the camera firmly anchored and under enough protection so that it can remain where it is for an entire year. At regular weekly intervals photograph the sun at exactly 12:00 UTC. At the end of the year, the image will show the characteristic "8" shape of the analemma. The one thing you will have to do is assure that the initial camera's view is such that the sun will always appear in the image at noontime, all year. If you start with the sun exactly in the middle, there may be a season when the sun at noon will not be in the camera's view.

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Emdrgreg

First answer by Emdrgreg. Last edit by Emdrgreg. Contributor trust: 2538 [recommend contributor ]. Question popularity: 2 [recommend question].

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