If you were to combine pictures of the sun taken every 10 days, from the same location and at the same time, you would end up with a picture similar to the one above. The astronomical term for this shape is an analemma, and is caused by "the Earth's motion around the Sun when combined with the tilt of the Earth's rotation axis. The Sun will appear at its highest point of the analemma during summer and at its lowest during winter."
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Enjoy.
http://www.spaceweather.com/glossary/tutulemma.htm
You should point out that this is repeated over the course of a year to produce the figure-eight image. So the photograph itself is pretty amazing considering that they took one (presumably every 10 days) from the same spot at the same angle over the course of a year.