In the post-World War II era the United States conducted hundreds of atmospheric nuclear tests, with multiple cameras capturing each event at around 2,400 frames per second. Like the Ark of the Covenant in Raiders of the Lost Ark, however, these treasures have largely been forgotten as they languished in high-security vaults around the country.
With time running out to archive this material (film decomposes over time), the Lawrence Livermore National Laboratory undertook a mammoth operation to capture these tests for posterity:
For the past five years, Lawrence Livermore National Laboratory (LLNL) weapon physicist Greg Spriggs and a crack team of film experts, archivists and software developers have been on a mission to hunt down, scan, reanalyze and declassify these decomposing films. The goals are to preserve the films’ content before it’s lost forever, and provide better data to the post-testing-era scientists who use computer codes to help certify that the aging U.S. nuclear deterrent remains safe, secure and effective.
And now they have shared some of this material with us all, by posting a bunch of the videos they've scanned to YouTube.
At the top of this post is the 'Turk' blast of 7 March 1955, conducted as part of 'Operation Teapot'. The terrifying video shows the blast effect of a 40 kiloton nuke, which is about twice the yield of the atomic bomb dropped on Nagasaki, though it pales into insignificance compared to the megaton devices now in the arsenals of a number of countries around the world.
But at least there's sane people in charge of those nuclear arsenals, amirite?