Cosm took the blueprint of a planetarium and made it feel like a stadium. The 87-foot LED dome uses five 8K cameras to capture livestreams, helping fans feel like they’re sitting front row at an NFL game. Fans are paying hundreds of dollars to experience it live. WSJ went behind the scenes at a Philadelphia Eagles game for “Sunday Night Football” to explain the tech that powers Cosm. Chapters: 0:00 The Cosm dome 0:45 Behind the scenes in Philadelphia 1:42 The camera tech 3:13 The screen tech 3: