Skip to comments.Astronomy Picture of the Day -- Airglow, Gegenschein, and Milky Way
Posted on 04/20/2013 4:26:09 PM PDT by SunkenCiv
Explanation: As far as the eye could see, it was a dark night at Las Campanas Observatory in the southern Atacama desert of Chile. But near local midnight on April 11, this mosaic of 3 minute long exposures revealed a green, unusually intense, atmospheric airglow stretching over thin clouds. Unlike aurorae powered by collisions with energetic charged particles and seen at high latitudes, the airglow is due to chemiluminescence, the production of light in a chemical reaction, and found around the globe. The chemical energy is provided by the Sun's extreme ultraviolet radiation. Like aurorae, the greenish hue of this airglow does originate at altitudes of 100 kilometers or so dominated by emission from excited oxygen atoms. The gegenschein, sunlight reflected by dust along the solar system's ecliptic plane was still visible on that night, a faint bluish cloud just right of picture center. At the far right, the Milky Way seems to rise from the mountain top perch of the Magellan telescopes. Left are the OGLE project and du Pont telescope domes.
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Not bad for a landscape shot.
He must have used an equatorial mount. If the shot was a minute long the stars would streak. I know, I’ve photographed the milky way myself in the desert.
Is that a tel on the horizon?
Wow! That is indeed amazing for an Earth based imagine! Though, I do prefer the pics you take from outer space. Always very nice of you to post them here first.
I can’t tel, ;’) but since it’s in Chile, I’ll guess no.
You sure about that? About 30 years ago, I remember trying to get streaking star pictures. I remember a 15 minute exposure would result in a tiny streak. I imagine 1 minute would hardly result in any streak at all.
Not sure I see the Gegenschein but that is one beautiful pic.
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