Solar system formation. Momentum distribution?

At work, a friend asked me how I thought the solar system was formed. I
asked him if he had ever heard of the accretion disc theory. He said
yes. He added that he thought the theory was badly flawed because the
theory predicts that the momentum and mass will be in the same place
when a system develops. Not, as it is with our system where the
majority of the mass is in the Sun while the majority of the momentum
is in the planets.

It seems to me that he does have a point. Where have I gone wrong here?

Errol

Starboard wrote:
He added that he thought the theory was badly flawed because the
theory predicts that the momentum and mass will be in the same place
when a system develops.

Correction. Not that the theory was flawed, but that the theory could
not accurately explain our system because of the stated momentum
problem.

Errol

"Sam Wormley" wrote in message
newsjkmh.199617$aJ.165447@attbi_s21...
Starboard wrote:
At work, a friend asked me how I thought the solar system was formed. I
asked him if he had ever heard of the accretion disc theory. He said
yes. He added that he thought the theory was badly flawed because the
theory predicts that the momentum and mass will be in the same place
when a system develops. Not, as it is with our system where the
majority of the mass is in the Sun while the majority of the momentum
is in the planets.

It seems to me that he does have a point. Where have I gone wrong here?



Recent material captured from Comet Wild 2 and observational evidence
from the stellar nurseries in M42 indicate that star formation (and
implied planetary formation) is likely much more violent than previously
thought.

"The Stardust spacecraft collected thousands of particles from comet
81P/Wild 2 and returned them to Earth for laboratory study. The
preliminary examination of these samples shows that the nonvolatile
portion of the comet is an unequilibrated assortment of materials that
have both presolar and solar system origin. The comet contains an
abundance of silicate grains that are much larger than predictions of
interstellar grain models, and many of these are high-temperature
minerals that appear to have formed in the inner regions of the solar
nebula. Their presence in a comet proves that the formation of the
solar system included mixing on the grandest scales".

The dominant principles involved in solar system formation include
o gravitational collapse
o conservation of angular momentum
o protostar magnetic fields, jets and solar wind

We have a lot to learn, but the idea that planet and other bodies
accreted from the planetary nebulae is well supported by the cratering
records on all colid bodies and the chemical analysis of bodies at
various zones in our planetary system.


Why yes oh wise one.

Starboard wrote:
At work, a friend asked me how I thought the solar system was formed. I
asked him if he had ever heard of the accretion disc theory. He said
yes. He added that he thought the theory was badly flawed because the
theory predicts that the momentum and mass will be in the same place
when a system develops. Not, as it is with our system where the
majority of the mass is in the Sun while the majority of the momentum
is in the planets.

This is a known issue. At the present time, it is believed to be
resolved: The angular momentum of the proto-Sun was transferred to the
planets over time through magnetic field interactions. That is, the
Sun's magnetic field accelerated particles out in the planetary system,
and its own rotation slowed as a result (Newton's third law). I don't
know the details, but you can probably find them by searching for
"solar system" and "angular momentum."

--
Brian Tung
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