Tuesday, 5 June 2012

Transit of Venus - Bloemfontein 2004

Date: 8 June 2004
Place: Boyden Observatory
Time: 06:30 – 14:00
Equipment: Nikon F3 (Film), 600mm mirror lens; 2X Converter.
Technique: Red filter. Also without filter. ND filter was used to reduce light.Image Processing: Negatives were scanned and digital images was finalised in Photoshop
Photographer: Hannes Pieterse

Information: Transit of Venus. Nobody alive today has seen a transit of Venus in front of the sun.  The last transit was in 1882.
          Sun's disk. During a transit, Venus can be seen from Earth as a small black disk moving across the face of the Sun. The duration of such transits is usually measured in hours (the transit of 2004 lasted six hours). A transit is similar to a solar eclipse by the Moon, but, although the diameter of Venus is almost 4 times that of the Moon, Venus appears much smaller because it is much farther away from Earth. Before the space age, observations of transits of Venus helped scientists use the parallax method to calculate the distance between the Sun and the Earth.
         Transits of Venus are among the rarest of predictable astronomical phenomena and currently occur in a pattern that repeats every 243 years, with pairs of transits eight years apart separated by long gaps of 121.5 years and 105.5 years. Before 2004, the last pair of transits were in December 1874 and December 1882. The first of a pair of transits of Venus in the beginning of the 21st century took place on June 8, 2004 (see Transit of Venus, 2004) and the next will be on June 6, 2012 (see Transit of Venus, 2012). After 2012, the next transits of Venus will be in December 2117 and December 2125.
          A transit of Venus can be safely observed by taking the same precautions as when observing the partial phases of a solar eclipse. Staring at the brilliant disk of the Sun (the photosphere) with the unprotected eye can quickly cause serious and often permanent eye damage. (Wikipedia information)


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