Think of this as a time dilation effect cometary effusion factor!
Another way to look at this is to think of our Solar system is "normal" with the requisite number of gas giants inward of Jupiter ~ EXCEPT they've already been boiled down to their rocky cores.
Still some juice in there though ~
Comet Cloud May Be Quite ThinIn 1950, Dutch astronomer Jan Oort noticed these comets come from every direction and have orbits that reach about 50,000 astronomical units (AU) away from the sun. Paul Weissman of the Jet Propulsion Laboratory and Alan Stern of the Southwest Research Institute believe that many of the planetesimals that planetary scientists thought were ejected into the Oort Cloud actually were pulverized while still among the giant planets. Computer models by Stern and Weissman show that most of the large chunks and other debris were destroyed in collisions amongst themselves before the giant planets had a chance to use their gravitational influence to whip survivors out toward the solar system's edge.
by Vanessa ThomasJupiter's Composition Throws Planet-formation Theories into DisarrayExamining four-year-old data, researchers have found significantly elevated levels of argon, krypton and xenon in Jupiter's atmosphere that may force a rethinking of theories about how the planet, and possibly the entire solar system, formed. While lead researcher Tobias Owen does not put much stock in the idea that Jupiter might have migrated inward to its present position, other scientists on the team say the idea merits consideration. Owen expects the probes will find similarly high levels of noble gases in Saturn, Uranus and Neptune. Hints of these gases have even been found in the thick atmosphere of Venus, another planet now begging more study.
by Robert Roy Britt