The "Sun" in Revolutions

--- Mark Landin wrote in <news:mcdt80pils5stk7lf7ao640fcrlqf01qrd@4ax.com>
>
> On Tue, 27 Apr 2004 13:27:48 +0200, Sandman <mr.DeleteThis@sandman.net> wrote:
>
> > In article <408e10bb$0$72201$abc4f4c3@news.wanadoo.nl>,
> > "Jumpkick" <nospam.DeleteThis@me.com> wrote:
> >
> > > thanks, mixed up things
> > >
> > > I did mean for the sun to lose mass/vanish somehow, because the red
> > > giant would indeed eat up half the solar system before collapsing
> > > into a white dwarf. Would a white dwarf be able to keep the solar
> > > system together?
> >
> > No, but there wouldn't be a solar system to keep together. :)
>
> Why wouldn't it? It's mass would be basically the same as Sol's
> current mass. Since physics says gravity acts as though it comes from
> a point-source, it doesn't matter if the mass that's generating the
> gravity is big (Sol) or small (white drawf).
>
> It's all about the mass...

Yes, but every atom in the universe, whereever it is located, exerts its
gravitational pull on every other atom in the universe, whereever it is
located... so two atom closer together pull at each other more strongly than
two atoms further apart... so as Sol's outer rim reaches further, the mass
of that outer rim pulls harder.

That is, the Law of Universal Gravitation:

f = G*m1*m2/(r*r)

f = gravitational force between two points
G = gravitational constant, 0.00000 00000 6673
m1= mass of first object
m2= mass of second object
r = distance between them

If you consider the pull of the entire sun, plus the effect of its outer rim
getting closer to other objects, eventually the square of the distance
between them will shrink (at an exponential rate) to cause the objects
gravitational force to appear to "yank" at each other... similarly to the
effect of magnets yanking at each other when they get close enough.

Or just imagine two Cheerios floating in your bowl of milk. If they get
close enough, they pull together and don't let go.

In article <mcdt80pils5stk7lf7ao640fcrlqf01qrd DeleteThis @4ax.com>,
Mark Landin <mark.landin DeleteThis @tdwilliamson.com> wrote:

> On Tue, 27 Apr 2004 13:27:48 +0200, Sandman <mr DeleteThis @sandman.net> wrote:
>
> >In article <408e10bb$0$72201$abc4f4c3@news.wanadoo.nl>,
> > "Jumpkick" <nospam DeleteThis @me.com> wrote:
> >
> >> thanks, mixed up things
> >>
> >> I did mean for the sun to lose mass/vanish somehow, because the red giant
> >> would indeed eat up half the solar system before collapsing into a white
> >> dwarf. Would a white dwarf be able to keep the solar system together?
> >
> >No, but there wouldn't be a solar system to keep together. :)
>
> Why wouldn't it? It's mass would be basically the same as Sol's
> current mass. Since physics says gravity acts as though it comes from
> a point-source, it doesn't matter if the mass that's generating the
> gravity is big (Sol) or small (white drawf).
>
> It's all about the mass...

The sun would have consumed the inner planets and would eventually attract and
consume (most) of the outer ones.

--
Sandman[.net]