Formation and evolution of the Solar System in turn far closer to the Sun when they formed (most likely in the range of 15–20 AU), and in 50% of simulations ended up opposite locations, with Uranus farther from the Sun than Neptune. According to the Nice model, after the formation of the Solar System, the orbits of all the giant planets continued to change slowly, influenced by their interaction with the large number of remaining planetesimals. After 500–600 million years (about 4 billion years ago) Jupiter and Saturn fell into a 2:1 resonance: Saturn orbited the Sun once for every two Jupiter orbits. This resonance created a
Jupiter mass from the Sun's center. Because the mass of Jupiter is so large compared to the other objects in the solar system, the effects of its gravity must be included when calculating satellite trajectories and the precise orbits of other bodies in the solar system, including Earth's moon and even Pluto. Theoretical models indicate that if Jupiter had much more mass than it does at present, its atmosphere would collapse, and the planet would shrink. For small changes in mass, the radius would not change appreciably, but above about (1.6 Jupiter masses) the interior would become so much more compressed under