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The analemma from Antarctica.

Thanks to Earth's spin-axis tilt and the slight eccentricity of its orbit, the Sun does not return to the same spot in our sky at the same time every day but instead traces out a "figure eight" over an entire year. Photographing this looping circuit --called the analemma--has tempted amateurs ever since Dennis di Cicco's pioneering conquest nearly four decades ago (S&T: June 1979, p. 536).

Apparently no one has ever recorded the analemma from a polar region. But I had this chance in 2014, while working as a European Space Agency research doctor at the French-Italian polar station Concordia (75[degrees] south latitude). There I witnessed the Antarctic summer's midnight Sun, as well as the 3-month-long polar night. That's exactly what makes the Antarctic analemma so intriguing: owing to the extreme location, only one lobe of the usual 8-shaped figure is visible--and it also appears almost vertical in the sky.

I began in late 2013, making exposures at 4 p.m. local time every week from December 28th until the following March 23rd, and again from September 17th to December 13th. Attempts to use a DSLR or analog camera proved unfruitful due to the low temperatures. So I used my Canon PowerShot A4000 IS HD compact digital camera in its "Fireworks" mode. Other settings were a 5.0-mm focal length, f/9 focal ratio, ISO 100, and V2-second exposure. Strong winds affected the camera's steadiness, and that's why some exposures appear wobbly. I shot the background picture at 9:15 a.m. to avoid direct sunlight. Finally, all the exposures were compiled in a single photo with the help of fellow astronomer Tilemachos Athanasiadis.

Adrianos Golemis

Larisa, Greece

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Title Annotation:Letters
Author:Golemis, Adrianos
Publication:Sky & Telescope
Article Type:Letter to the editor
Date:Feb 1, 2016
Words:280
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