Article: <5f7182$edt@dfw-ixnews7.ix.netcom.com>
From: saquo@ix.netcom.com(Nancy )
Subject: LONG ELLIPSE Orbits (was Re: Hale-Bopp THEN and NOW)
Date: 28 Feb 1997 16:30:58 GMT
In article: <5f1iue$rra$1@towncrier.osf.org> David
Brooks writes:
>> 1. Picture the comet with the Sun to its left as it
exits the
>> Solar System. .. Draw the vectors at this point, as a
straight
>> line from the center of the Sun on out into space, which
>> will be a line parallel to the path the exiting comet is
taking.
>> ZetaTalk[TM]
>
> Okay, I just drew the pictures ... But the gravitational
force
> pointing back at the sun isn't parallel to the path the
exiting
> comet is taking. It cuts across the path at an angle.
> dbrooks@x.org (David Brooks)
>
>> 2. For the second vector, draw a second line, this one
pushing
>> to the right, as this is the direction the comet is
moving in,
>> away from the first vector drawn from the center of the
Sun.
>> ZetaTalk[TM]
>
> there is a vector decelerating the comet's rightward motion.
> Further out, at the widest point, it becomes a vector
accelerating
> the leftward motion. I added the two vectors. Acceleration
to
> the left.
> dbrooks@x.org (David Brooks)
(Begin ZetaTalk[TM])
By what logic did you ADD the two forces? What IS the force
pushing the comet to the right, in the first place, and likewise
what IS the force you imagine is pushing from the right, to
decelerate the comet as you put it? One could give the rightward
force several names that humans would relate to - centrifugal
force, for one. We have stated that comets go round the Sun, not
into it, due to the push away from the Solar Wind. And in fact,
the comet widens its ellipse DUE somewhat to that factor, as it
seeks less Solar Wind by moving outward away from the intensity,
to the SIDE. All this gives it a RIGHTWARDS push, in our diagram,
but no LEFTWARD push. Can't just invent it! Where'd it come from?
(End ZetaTalk[TM]