Thirty-nine years ago today, on April 18, 1986 (March 10, 1986 lunar calendar), the launch of the American Hercules rocket failed. The American Hercules rocket exploded after launch. On April 18, 1986, a Hercules rocket of the United States Air Force was launched from Vandenberg Air Force Base in southern California, and exploded a few seconds later. The explosion destroyed the base's launch pad and the KH-11 secret electronic communication satellite it was carrying worth more than $300 million, injuring 58 people. A huge orange fireball was raised, and a thick cloud of toxic gas filled the sky, scattering rocket fragments all over the base. This is another launch failure after the explosion of the KH-11 reconnaissance satellite launched with this rocket on August 28 last year.