Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: stana on 07/06/2007 00:04:29
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How are these big comets that threaten to hit the earth formed? are they just broken off planets?
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Hello Stana
Yes. They are pieces of volcanic rock which have broken away from the gravity field of the planet they belonged to, simply spinning out of control, because they are no longer held in the gravity where they previously belonged. Who knows, perhaps they are still the result of atomic blasts in some other area which broke the field of gravity somewhere else.....
Not a terribly scientific answer.... but that is how I see them. In my world one calls them shooting stars and one is prompted to wish a wish when you see a flying meteor.
Actually, when I was a little child (loooooong looooong ago that is) I was on a mountain top with my parents and they showed me a HUGE round blackened rock and they told me it was a meteorite which fell there from some other planet etc etc. See how important parenting is ? [8D]
Anyway, I look forward to seeing whether some other astrologist or geologist can give a more erudite reply to your question. [:I]
Namaste
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Comets are probably reminants of the planetary disk which formed the sun and the planets. They have stayed cold for billions of years. Basically some of the dust and gasses around at the start of the solar system condensed, and slowly coalesced (joined together) to form a lump and then not a lot more happened for billions of years until something made them change diection into the centre of the solar system where the heat makes them evaporate and solar wind and the solar wind blows the resulting gas into a tail.
They are different from asteroids which mostly were lumps of planet or proto planet.