If recent research is correct, Astronomers have explained how the outer gas giant planets in our solar system were able to achieve their current orbits without harming the inner rocky planets.
The research offers a simple solution to a problem that has puzzled scientists for years – since the gas giants were formed closer to the sun, how did they move to their current orbits without destroying the rocky planets or ejecting them from the solar system?
Dr. David Nesvorny discovered a possible solution to the problem when working with a computer model. His simulations showed that a slow, outwardly moving Jupiter caused some of the inner planets (most importanly Earth) to collide with each other or eject from the solar system. To solve this understandably bad problem, some of his colleagues suggested Uranus and Neptune caused Jupiter to “jump” outwards in a quick motion that spared the inner planets. When Dr. Nesvorny ran the simulations to test the theory, he found that while a jumping Jupiter did stop harm to the inner rocky planets it also caused Uranus and Neptune to eject from the solar system. This clearly wasn’t correct.
The complete solution to the problem came when Dr. Nesvorny considered what would happen if the early solar system had five gas giants instead of four. When he added an extra Neptune/Uranus like planet, everything worked! He was able to show that a fifth planet can cause Jupiter to jump which leaves the inner planets and gas giants in tact (at the expense of the fifth gas gaint).
Dr Nesvorny’s work represents another example of the amazing fine tuning God used when designed a home for us (a.k.a the Anthropic Principle).