solar-system-formation

Planets do not always stay where they form. Torques from the gas disk around a young star, resonances between planets, and later gravitational scattering can all shift orbits. Migration explains hot Jupiters, tightly packed super-Earths, and possibly Mars's small size.

Every planet in our solar system grew from a thin disk of gas and dust that surrounded the young Sun 4.6 billion years ago. Modern telescopes now image these disks around other stars in stunning detail, revealing a process far more violent, chaotic, and fast than scientists once imagined.