Simulation Shows Solar System Once had an Extra Gas Giant
— A new study published on arXiv.org shows that, based on computer simulations, Jupiter, Saturn, Uranus and Neptune may not have been the only gas giants in our solar system. According to David Nesvorny from Colorado’s Southwest Research Institute, our current solar system could never have happened without the existence of a fifth planet.
In an effort to determine just how the solar system was formed, Nesvorny performed a series of some 6,000 computer simulations. When using just the four giant planets, every simulation found that they were too large and ended up destroying each other. In the simulations where they did manage to make it in one piece, the rocky planets such as Mars and Venus, were instead destroyed. According to his results, the current solar system structure would have a very low probability of occurring if it started with only four rocky planets and four gas planets.
After running these simulations, Nesvorny decided to add a fifth large planet into the mix. With the addition of this large planet, results found that the odds of our current solar system increased significantly.
The most successful simulations show that Jupiter, Saturn, Uranus, Neptune and a fifth planet, similar to that of Neptune or Uranus, started out all tightly packed and orbiting some 15 times further from the sun then our planet Earth. The lighter planets are sent out further by Jupiter and Saturn.A close encounter with Jupiter then ejects this mysterious fifth planet out of the solar system.
Recent discoveries of free-floating planets in interstellar space show that the ejection of planets could have been common, according to the study.