Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: AlphBravo on 08/12/2005 23:14:21
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I have often wondered about those clouds are they static, in that as they are passed by on the revolution of the planet, and does the planet absorb much of this dust/debris as it does pass by, the other question though is how long have they been there, is there a way of determining such?
Does that prove maybe it was a comet that did those dinosaurs,(I see now, that they reckon it was toxic gas from the volcanoes now?)
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Please rephrase this question more clearly and completely if you want any sort of sensible answer it is just not understandable.
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Ok then the dust clouds known as the Leonids and the other one (the name escapes me!)
Anyway the question is: when were they formed?
(Are they static in space)
But also will the earth draw those particles etc in it's own orbit thus eliminating them.
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Alph - you've prompted me to do a search and I've found an astronomy site which looks very interesting and useful. The FAQ page is probably the best place to start investigating this site:
http://star.arm.ac.uk/FAQ.html
(The site covers a variety of interesting topics, e.g. beginner's guide to what you can see in the night sky, explanation of how stars form, whether earth is going to be destroyed by a comet, ...)
The site seems to imply the Leonid dust trails are static and gradually disperse over a few centuries.
And it looks like the other dust trail (whose name you can't remember) is the PERSEID meteor trail.
Hope this helps.
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The Leonid dust clouds are NOT static they are in orbit around the sun like everything else. They are supposed to be related to a comet (I can't be sure which at the moment I think it is called Tempel but it's in the text books) that has an orbital period of 33 years so the densest bits seem to come round every 33 years or so. The big showers were in 1833 1866 1899 1933 1966 and around 2000 so it is tailing off now.
Because of weak gravitational interactions among the particles themselves or possibly electromagnetic interactions the particles appear to be strung out in the orbit like braided strings. You can see similar effects in the detailed pictures of the rings of Saturn.
Sometimes the earth passes through a dense bit and someitimes it passes through a thin bit. The astrononmers are getting better at guessing ehere the dense bits are and wheather the earth will pass through them in any year but they are still not very accurate.
Every meteor only makes its trip through the atmosphere once so the clouds are clealy being depleted but a thirty three year elliptical orbit stretches out beyond the orbit of Saturn so there's quite a lot of space there.
As to when they were formed its not very clear. The general view is that periodc comets are comets that came into the vicinity of the sun and were given periodic orbits by inteaction with one of the panets. It was reckoned that the start of the displays in 1833 was due to the comet passing quite close to Jupiter and having its orbit changed to cross the orbit of the earth but the comet had been around long before that.
Learn, create, test and tell
evolution rules in all things
God says so!