News Astronomy Here’s the best timeline yet for the Milky Way’s big events Our galaxy formed its original disk 2 billion years before its stellar halo The Milky Way arches over the Large Sky Area Multi-Object Fiber Spectroscopic Telescope in China, one of the observatories whose data has revealed that our galaxy began forming a disk of stars surprisingly fast after the Big Bang. Yingwei Chen Share this:EmailFacebookTwitterPinterestPocketRedditPrint By Ken Croswell March 23, 2022 at 12:00 pm A new analysis of nearly a quarter million stars puts firm ages on the most momentous pages from our galaxy’s life story.