Thread: A question ...
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Old Dec 31 2008, 02:54 AM   #70
ghost8772
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Default Re: A question ...

Quote:
Originally Posted by Danel View Post
Well, from what I know, objects on a hyperbolic orbit that take them from the Kruiper belt or Oort cloud close to a star, have the most speed as they aproach the point of orbit closest to the star.

In otherwards, an object in a 250 year hyperbolic orbit, would only spend a brief time of that orbit turning around to head back out of the inner system. Like only half year at most. (See Haleys comet, etc..)

So the 50 years of thread fall would not be due the planet being in a close orbit for fifty years, but from thread being depositied close to Pern, and gravity eventualy attracting it over time to fall on the planet.
yep, but trying to think through the physics of it. a cometary tail would mean that Pern would have thread when it initially pierced the tail, and the thread would fall for a few weeks at most after. with no rhyme or reason to the fall. Once the red star passed outside Pern's orbit again, then there would be threadfall about once every six months. Again, a steady fall when pern passed through the tail, but probably not the falls Anne described.
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