AstroGAS

06/30/07

Venus, Saturne et al.
On Saturday 30 June 2007 before sunset, weather conditions improved as announced. Venus could be spotted without instruments. Telescopic views were impaired by poor seeing. Saturn could not be seen at the telescopes, even using filters. At that time, there was an aircraft corridor in front of Venus and Saturn, hence the first picture in the gallery below - after drastic contrast enhancement, it shows Saturn at the upper left corner.
As dusk was in progress, Saturn became a telescopic, then a binocular, then a naked-eye object. Wide-field images were taken - see second picture.
After 22h, Venus and Saturn were low in a rather dark, very turbulent sky. The third image was strongly enhanced in sharpness to show Saturn´s rings, and compressed in dynamic range to show some phase on Venus: this introduces some artifacts and also a "Malevich painting" aspect for the sky.
As a nice surprise, seeing improved greatly during the evening. The Envisat satellite was seen with some detail, then Jupiter's cloud bands, shadow of Ganymede and Great Red Spot (pale salmon, in fact) were clearly revealed. The Galilean satellites could be told from one another according to hue, apparent diameter and overall brightness.
Turbulence increased again while observing the companion of Antares and the rising full Moon.
Before dawn, turbulence had decreased again, but there were thin clouds. Mars was thus seen as a subdued, reduced contrast disk definitely showing a phase, but no polar cap anymore, and only a hint of Terra Sirenum.

Photo gallery - Saturn, Venus, airplane

Images #1 and #3: apo 200/1600, modified Canon EOS 5D, ISO 100.
Image #1: 1/1250s, FOV 1.0° / Image #3: 1/8s, FOV 0.8°.
Image #2: 200mm f/4, Nikon D100, ISO 200, 1/4s, FOV 7.5°.

jld







Article posté à  13:40:00, le 06/30/07 par ejehin - Catégorie : AstroPhotos


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