Intergalactic Collisions Created Milky Way’s Spiral ArmsThe Milky Way’s spiral arms formed due to two intergalactic crashes with the nearby dwarf elliptical galaxy Sagittarius over the last two billion years and a third collision is dueSavePrintEpoch Times Staff9/14/2011|Updated: 10/1/2015We had a problem loading this article. Please enable javascript or use a different browser. If the issue persists, please visit our help center.Share this articleLeave a commentEpoch Times StaffAuthorAuthor’s Selected ArticlesDay in Photos: Military Exercises in Poland, UK Welcomes Trump, and 10 Million-Year-Old SkeletonSep 17, 2025New Details on Kirk SuspectSep 17, 2025Day in Photos: Mexican Independence Day, Israel Advances on Gaza, and Protests in ColombiaSep 16, 2025Day in Photos: UK Preps for Trump’s Visit, Military Exercises in Belarus, and Bird Singing CompetitionSep 15, 2025Related TopicsScienceSpace Astronomy