French nuclear test Licorne, Mururoa Atoll, French Polynesia, July 3, 1970. Note: this explosion in its many stages appears all over the internet misidentified as the Canopus blast from August 1968. However these photos are from Atolls de l’atome, a definitive book about French nuclear testing in the Pacific, and are there identified by author Bernard Dumortier as Licorne.
This world, then the fireworks.