Incredible as it may sound, only seven times has someone ever managed to successfully image the solar analemma as a
multi-exposure on a single piece of film. An analemma is basically the figure "8" loop that results when one observes
the position of the sun at the same time during the day over the course of a year. As a result of the earth's tilt about
its axis (23.5°) and its elliptical orbit about the sun, the location of the sun is not constant from day to day when
observed at the same time on each day over a period of twelve months. Furthermore, this loop will be inclined at
different angles depending on one's geographical latitude.
As suggested by the relatively few number of successfully completed analemmas (seven total including the pioneering
photo in 1979), the imaging of the sun over local skies during the course of twelve months is considered one of the most
difficult and demanding astronomical phenomena to image. The analemma presented below is one of TEN analemmas
completed during a marathon started in 2001 in an attempt to document the complete range of analemmas from sunrise
to sunset (see here). It is further unique as it represents
the second of eight analemmas ever imaged during a single calendar year and certainly the second analemma ever imaged
in Greece and the first analemma ever imaged perfectly vertical on the southern meridian.
Note: For an animation involving the analemma at
13:00:00 UT+2 and which beautifully documents the actual motion of the sun during twelve
consecutive months when observed at precisely 13:00:00 UT+2, please see the example
here.
Note: As noted elsewhere, more men have walked on the moon than have successfully
photographed the analemma (see S&T, Dec/2003: 73).
Body: Sun Mass: 332,900 x Earth Mean Eq Diameter: 109.1 x Earth Distance: 147 million km RA / Dec: 18h 46m 59s / -23° 00' Diameter: 32.53' Magnitude: -26.8 |
|
Date: Jan 12, 2002 - Dec 21, 2002 12:28:16 UT+2 Location: Athens, Greece Equipment: Canon A-1 Canon FD 24 mm @ f/11 Fuji Super HQ 200 Baadar Solar Filter ND5 Exposures: 1/60 sec 41 multiple exposures + 1 foreground exposure Software: Photoshop V6 Processing: Layers Resampling (25%) JPG Compression |