View Details | A simulation of the outer solar system’s early evolution known as the Nice model tracks the planets’ orbits from soon after the birth of the solar system through the period of late heavy bombardment and beyond. At the simulation’s start, a massive reservoir of icy debris, a forerunner of today’s Kuiper Belt, lies beyond the outer planets. Credit: Illustration: Mark A. Gerlick / space-art.co.uk; Graph: D. Kring; Simulations: Adapted from Gomes et al./Nature 2005