Quote Originally Posted by BetterSense View Post
http://arxiv.org/pdf/1106.3141v1
Now, I didn't know what an analemma is until I saw this, so let me explain that it's a multiple-exposure photo of the sun, which forms a figure-8 pattern in the sky.
Not really accurate, probably due to poor grammar. An analemma isn't a multiple exposure photo, it's the pattern made by the sun when solar observations (not necessarily photographs) are made at a certain standardized clock time each day, and reflects the combined effects of the earth's changing speed in its slightly elliptical orbit, and the tilt of the earth's spin axis relative to the plane of its orbit around the sun. Analemma drawings are very common on sundials and on globes.

The photo in your post is by Dennis DiCicco, who was the first known to photograph it in this way. See: http://www.twanight.org/newTWAN/photos.asp?ID=3001422

There are a number of analemma photos by one prolific and well-known photographer at:
http://www.perseus.gr/Astro-Solar-Analemma.htm along with the data on how he made his exposures.

Lee