Watch these declassified nuclear test films on YouTube

A physicist and film expert are working to restore the decades-old films.

National Nuclear Security Administration / Nevada Site Office, via Wikimedia

There's something both beautiful and unnerving about a mushroom cloud. The United States conducted around 216 atmospheric nuclear tests between 1945 and 1992, many taking place in Nevada and the Pacific Proving Grounds. Now, rare videos of those detonations are declassified and available to the public for the first time.

Greg Spriggs, a nuclear weapon physicist at the Lawrence Livermore National Laboratory, and a film expert named Jim Moye are working to locate and preserve the videos. Spriggs estimates they've found about 6,500 out of 10,000 films, but so far they've only scanned around 4,200 and analyzed 400-500. Today, the laboratory uploaded 64 declassified videos to its YouTube channel.

Spriggs believes it will take at least another two years to find and scan all the films. Declassifying them could take even longer, since that requires a military review. But, Spriggs hopes they'll lead to valuable benchmark data that can be used by future weapon physicists. "By looking at these films, we found a lot of different pieces of information that had not been analyzed back in the '50s, and we're discovering new things about these detonations that have never been seen before," he said.