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Sample records for gegenschein

  1. The Gegenschein and the relation of Danjon

    International Nuclear Information System (INIS)

    Robley, Robert

    1979-01-01

    Observation of the zodiac light in the antisun during a solar cycle shows behavior similar to that of the eclipsed moon, however with a time shift of about 2 years. It is shown that both effects are related to the behavior of the solar corona during a solar cycle [fr

  2. Solar Games at Paranal

    Science.gov (United States)

    2008-05-01

    Cerro Paranal, home of ESO's Very Large Telescope, is certainly one of the best astronomical sites on the planet. Stunning images, obtained by ESO staff at Paranal, of the green and blue flashes, as well as of the so-called 'Gegenschein', are real cases in point. Green Flash at Paranal ESO PR Photo 12a/08 Green Flash at Paranal The Earth's atmosphere is a gigantic prism that disperses sunlight. In the most ideal atmospheric conditions, such as those found regularly above Cerro Paranal, this will lead to the appearance of so-called green and blue flashes at sunset. The phenomenon is so popular on the site that it is now the tradition for the Paranal staff to gather daily on the telescope platform to observe the sunset and its possible green flash before starting their long night of observations. The green and blue flashes are fleeting events that require an unobstructed view of the setting Sun, and a very stable atmosphere. These conditions are very often met at Paranal, a 2635m high mountain in the Chilean Atacama Desert, where the sky is cloudless more than 300 days a year. Paranal is home of ESO's Very Large Telescope, an ensemble of four 8.2-m telescopes and four 1.8-m Auxiliary Telescopes that together form the world's most advanced optical telescope. Blue Flash at Paranal ESO PR Photo 12b/08 Blue Flash at Paranal ESO staff St├ęphane Guisard has been chasing green flashes for many years and has been able to capture them on many occasions. The picture shown above is one of many examples from his collection. "The most challenging is to capture the green flash while still seeing the rest of the Sun with all its colours," says Guisard. His colleague Guillaume Blanchard was even luckier. On Christmas Eve, as he was one of the few to follow the tradition of looking at the sunset, he had the chance to immortalise a blue flash using his hobby telescope. ESO astronomer Yuri Beletsky also likes to take photographs from Paranal, but he prefers the night views. This allows