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: 10/1/2015Share this articleLeave a commentEpoch Times StaffAuthorAuthor’s Selected ArticlesAmerica in Photos: Floods in Texas, the Original Alcatraz, and Independence Day CelebrationsJul 05, 2025In Photos: July 4th CelebrationsJul 05, 2025Day in Photos: US Independence Day, Gas Station Explosion, Diogo Jota TributeJul 04, 2025July the Fourth in 12 Charts: Food, Fireworks, Travel, and MoreJul 04, 2025Related TopicsScienceSpace Astronomy