Posted on 12/22/2013 8:27:30 AM PST by SunkenCiv
Explanation: If you went outside at exactly the same time every day and took a picture that included the Sun, how would the Sun's position change? With great planning and effort, such a series of images can be taken. The figure-8 path the Sun follows over the course of a year is called an analemma. Yesterday, the Winter Solstice day in Earth's northern hemisphere, the Sun appeared at the bottom of the analemma. Analemmas created from different latitudes would appear at least slightly different, as well as analemmas created at a different time each day. With even greater planning and effort, the series can include a total eclipse of the Sun as one of the images. Pictured is such a total solar eclipse analemma or Tutulemma - a term coined by the photographers based on the Turkish word for eclipse. The above composite image sequence was recorded from Turkey starting in 2005. The base image for the sequence is from the total phase of a solar eclipse as viewed from Side, Turkey on 2006 March 29. Venus was also visible during totality, toward the lower right.
(Excerpt) Read more at 129.164.179.22 ...
[Credit & Copyright: Cenk E. Tezel and Tunç Tezel (TWAN]
They must have calculated the eclipse near the solstice and figured from there. Outstanding effort and thanks for the post, SC.
Thanks for sharing that! What an amazing composite. Beautiful.
I suppose that if you created an analemma at the equator, it would be a more symmetrical figure 8?
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No. The southern loop of the analemma is always wider because Earth is closer to the sun (perihelion) in January.
Is that where the infinity symbol originated?
The “lazy 8” for infinity... hmm... that’s a modern use of an old Greek letter... guess it’s time to whip out the search engine.
Thanks!
My pleasure.
http://scienceblogs.com/startswithabang/2009/08/26/why-our-analemma-looks-like-a/
[snip] So, at the North Pole, the analemma would be completely upright (an 8 with the small loop at the top), and you’d only be able to see the top half of it. If you headed south, once you drop below the Arctic Circle, you’d be able to see the entire analemma, and it would start to tilt to one side the closer to the horizon you photographed it. By time you got down to the equator, the analemma would be completely horizontal. Then, as you continued to go south, it would continue rotating so that the small loop was beneath the large loop in the sky. Once you crossed the Antarctic Circle, the analemma, now nearly completely inverted, would start to disappear, until only the lower 50% was visible from the South Pole. [/snip]
That’s a great reference, thanks SC!
I remember when in Australia years ago getting thrown by the different appearance of familiar constellations, and just the motion in the sky of celestial objects.
Why Tutu?
That poses a Tutulemma...
Ah, yes...Tutu is a ‘de-lemma’ of sorts. I knew him maybe 35 years ago when he was supposedly apart of the ‘Renewal’ in the Anglican Church. Don’t think that was so real, based on what I have seen/heard more recently.
He’s apparently become a Dinnermasher Disciple. You’d think he’d know about Sodom and Gomorrah...
Excellent paper at the link. Thanks.
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