The 6 Ingredients You Need to Build a PLANET

Here's a pile of space dust. Your job is to turn it into a world. You get one newborn star, a disk of gas, and all the time you need. Along the way, you'll hit problems that scientists are still working out. Step by step, we go from grains as fine as smoke to fluffy clumps and pebbles, hit the meter-size barrier, watch a crowd of pebbles collapse into a planetesimal, grow planetary embryos with iron cores, cross the snow line where giant planets grab their gas, and finish with the giant impact that probably made the Moon. Each stage adds an ingredient to the recipe, and at the end we see why it isn't nature's only recipe. CHAPTERS 0:00 The job 1:13 Make it stick 2:33 The wall 3:33 Strength in numbers 4:50 The rich get richer 6:11 Right place, right time 7:35 The crash phase 8:34 Not one recipe A NOTE ON ACCURACY Time is compressed: about 100 million years in one film, and every clock time is approximate. Sizes are exaggerated where the film says so. Some steps are still debated, and the film labels them that way: how planetesimals form, the details of Theia and the Moon-forming impact, and where Earth's water came from. Arrokoth, HL Tauri, PDS 70 and the meteorite slices are drawings, not telescope or spacecraft images. SOURCES (selection) Youdin & Kenyon, From disks to planets: https://arxiv.org/pdf/1206.0738 Birnstiel, Fang & Johansen, Dust evolution and the formation of planetesimals: https://arxiv.org/pdf/1604.05842v1 Laibe et al., Revisiting the radial-drift barrier: https://arxiv.org/pdf/1111.3083 Morbidelli et al., Asteroids were born big: https://arxiv.org/pdf/0907.2512 Connelly et al. (2012), Chronology of the solar system's oldest solids: https://researchportalplus.anu.edu.au... NASA Astrobiology, New Horizons and the planetary formation puzzle (Arrokoth): https://astrobiology.nasa.gov/news/ne... Kokubo & Ida, Dynamics and accretion of planetesimals: https://arxiv.org/pdf/1212.1558 Raymond et al., Dynamical models of terrestrial planet formation: https://arxiv.org/pdf/0906.4369 The Moon-forming impact as a constraint: https://arxiv.org/pdf/2411.14709 Peslier et al., Origin of Earth's water: https://arxiv.org/pdf/1912.04361 Bryson et al., Demographics of Kepler's Earths and super-Earths: https://arxiv.org/pdf/2209.04047 #planets #astronomy #space