Science: Whence the Planets?

Ever since man perceived that the solar system is a cohort of planets revolving around a central sun, at different distances but in the same direction and in almost the same plane, he has wondered how it all started. Pierre Laplace, French mathematician (1749-1827), devised the celebrated "nebular hypothesis": that the solar system was originally a diffuse, whirling, gaseous mass. As this nebular mass became smaller and denser, it whirled faster, until centrifugal force threw off a ring of gas. The process was repeated, each gas ring coalescing into a planet and the sun finally settling down to its present calm...

Want the full story?

Subscribe Now

Subscribe
Subscribe

Get TIME the way you want it

  • One Week Digital Pass — $4.99
  • Monthly Pay-As-You-Go DIGITAL ACCESS$2.99
  • One Year ALL ACCESSJust $30!   Best Deal!
    Print Magazine + Digital Edition + Subscriber-only Content on TIME.com

Learn more about the benefits of being a TIME subscriber

If you are already a subscriber sign up — registration is free!