Thousands of films of such blasts, made from 1945 through 1962, were analyzed and locked away in high-security vaults. It's likely no one has seen the footage for decades.



But on March 14, after more than 55 years of collecting dust, the US declassified 750 of the high-speed films — and released dozens of the digital scans on YouTube. We first heard about the movies from the writer Sarah Zhang on Twitter.