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Old October 5th 03, 03:25 AM
Gordon D. Pusch
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Default Hubble Uncovers Smallest Moons Yet Seen Around Uranus

Trakar writes:

On 03 Oct 2003 11:49:06 -0500, (Gordon D.
Pusch) wrote:

Gas-giant planets and "terrestrial" planest are believed to form by
different physical mechanisms. "Terrestrial" planets are believed
to form by collisional accretion of "planetesimals," whereas "gas giant"
planets are believed to form by accretion from a sub-disk embedded within
the main protoplanetary disk that itself resembles a "mini solar system."

Could you reference a good site (web, book, or paper) on this for me?
I was under the general impression that it was a similar process, that
it was just a matter of there being greater gasseous material to
accumulate in the region of gas-giant formation.

Do a Google search on "gas-giant formation" and you will pull up
approximately 9340 references. You can further specialize your search
by adding the keywords for the two competing gas-giant formation models:
"runaway core accretion" or "disk instability;" the latter "disk" model
is the "mini solar-system" model I referred to.

(The "disk instability" model has been gaining support over the older
"runaway core accretion" model, since the core accretion model does not
appear to be able to form a giant planet fast enough to beat the ignition
and "T-tauri phase" of the system's protostar. The "T tauri" phase produces
Very strong stellar winds that blow away most of the gas remaining in the
protoplanetary disk, terminating gas accretion onto the giant planets.)

-- Gordon D. Pusch

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