Nebadon 600 Billion BC
“600,000,000,000 years ago the height of the Andronover energy-mobilization period was attained; the nebula had acquired its maximum of mass.” (The Urantia Book, 652:7). 400,000,000,000 years ago began the recaptive period of the Andronover nebula...It was scarcely a million years subsequent to this epoch that Michael of Nebadon, a Creator Son of Paradise, selected this disintegrating nebula as the site of his adventure in universe building." (The Urantia Book, 653:7 and 654:1)