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These panels show the evolution of selected particles within the calculations that attain nearly planar (i < 40°) Neptune-crossing orbits within the final 500 Myr of the integration. “Collectively, these examples indicate that P9-facilitated dynamics can naturally produce objects similar to those depicted in Figure 1” (the previous figure), the researchers explain. The top, middle, and bottom panels depict the time series of the semimajor axis, perihelion distance, and inclination, respectively. The rate of chaotic diffusion greatly increases when particles attain Neptune-crossing trajectories. Image Credit: Batygin et al. 2024.