Zodiacal light semantics (25 Sep 2007)
Zodiacal light semantics (25 Sep 2007)
Okay, a "false dawn" isn't a dawn by self-definition, so "false dawn" is obviously a metaphorical term applied to a phenomenon. Yet the phrase "Once considered a false dawn" implies that people who used the term were misguided. Surely the phenomenon was just called a false dawn, and now it's called something else.
False dawn
It says in the last sentence it's also bright for people in the Northern Hemisphrere in March and April. Shouldn't, then, the reference in the first sentence be Southern Hemisphere? Steve
- geckzilla
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According to a wiki entry on the topic it can happen both during spring and autumn, signots. In spring it happens after the evening twilight while in autumn it happens before the morning twilight.
http://en.wikipedia.org/wiki/Zodiacal_light
http://en.wikipedia.org/wiki/Zodiacal_light
- Chris Peterson
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From a dark site it is visible year round. It's simply more prominent near the equinoxes. The bottom image at http://www.cloudbait.com/gallery/gallery_meteor.html was taken in mid-November.geckzilla wrote:According to a wiki entry on the topic it can happen both during spring and autumn, signots. In spring it happens after the evening twilight while in autumn it happens before the morning twilight.
Chris
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Dusk, not dawn
The picture was taken at dusk, not dawn. The bright "blob" near the horizon is Venus, and Regulus can be made out below it. Lower still, Saturn is about to set. Arcturus, Spica, Porrima, and Denebola are clearly visible in the central area. The first clue was the angle of the ecliptic, which leans to the left at dawn and to the right at dusk in the Southern Hemisphere.