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Photographer's Note

A transit of Venus across the Sun takes place when the planet Venus passes directly between the Sun and Earth, obscuring a small portion of the 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. 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. (from Wikipedia) The next transit will occur on June 6, 2012 (see http://www.transitofvenus.org/2012.htm )

Le transit de Vénus survient lorsque cette planète passe directement entre la Terre et le soleil. C’est le même principe que pour une éclipse solaire par la lune, à la différence que même si Vénus est plus grande que la lune, elle est tellement plus éloignée de la Terre qu’elle n’apparaît que comme un petit cercle noir se déplaçant devant le disque solaire. Le temps de transit est de plusieurs heures. Les transits de Vénus sont parmi les évènements astronomiques périodiques les plus rares, suivant un cycle de 243 ans pendant lequel on observera deux transits consécutifs séparés par un interval de 8 ans, les paires de transits étant elle-mêmes séparées par 121.5 ou 105.5 ans. Le transit ayant précédé celui de 2004 était en décembre 1882, et nous sommes maintenant presque à mi-chemin du prochain qui aura lieu le 6 juin 2012. (voir http://www.transitofvenus.org/2012.htm )

Technical data:

Location
Lat 46 45’ 57”
Long -71 28’ 13”

Date & Time
June 8, 2004
6h55 EST (10h55 Universal time)

Equipment
Olympus OM-2 body fitted on a skyview 120mm telescope (F1000) with 2x Barlow teleconverter, attached to a motorized equatorial mount. Exposure time was 5 seconds. The natural yellow color is obtained thanks to an R-G filter (thousand oaks optical). The darker patches are caused by clouds in front of the sun. A couple of sunspots are also visibles as two small specks.

Film used: Fuji provia100F color slide film

Slide was scanned with a Nikon Super Coolscan 4000 ED film scanner and slightly cropped, resized and framed.

I also posted on TL a composite picture of the transit taken earlier in the morning without the telescope small black dot

Dorota, JPlumb, mortijo, jcdurka1, vinicio, zmey, scobert, h_sedghi marcou esta nota como útil

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