Planetesimals main content.


Part of Hall of Meteorites.


The small particles drifting in orbit around the developing Sun were initially no bigger than grains of sand. But over time, the particles clustered together, building up into larger and larger bodies, known as planetesimals. While these objects were still relatively small, the growth process was fairly slow and steady. But once planetesimals reached the size of the island of Manhattan, the solar system became a more chaotic and violent place, with p