Tag Archives: nuclear tests

More films of early nuclear test released

The uncertainty of science: Researchers have released more films taken during numerous 1950s and 1960s atmospheric nuclear bomb tests to the public, while noting that modern computer simulations of nuclear explosions, based on the data taken from these early tests, could be as much as 30 percent in error.

Ten years ago, Spriggs was asked to write a computer code related to nuclear weapons effects, but his calculations didn’t agree with what was published in the 1950s and ’60s. When he dug in to find out why there was a discrepancy, he discovered that the manual measurements made in the ’50s and ’60s were off, in some cases by 20 percent to 30 percent. His new mission had become clear: reanalyze all the nuclear test films to ensure future computer simulations would be validated.

“It was driving me nuts,” Spriggs said. “No matter what I did, I couldn’t get my calculations to agree. Eventually, I came to the conclusion that the data must be off. To prove our simulations are correct, we rely on quality benchmark data. That’s why this project is so important. It is providing the data our physicists need to ensure our deterrent remains viable into the future.”

They are scanning and reanalyzing all the footage so that they can refine their models. They also note that the analysis done in the 50s and 60s was actually quite good, but today’s computer technology allows for greater accuracy and objectivity.

Hat tip Wayne DeVette.


Want to watch a nuclear bomb go off? You can!

Engineers at Lawrence Livermore National Laboratory (LLNL) have obtained declassified films of many of the nuclear tests performed by the U.S. from 1945 to 1962 and are digitally scanning them and preserving them for posterity.

Conducted by LLNL weapon physicist Greg Spriggs and a team of film experts, archivists, and software developers, the project’s goal was to track down as many as possible of the ten-thousand 2,400 frames per second reels of film. This was because the cine film, and its immense historical and scientific value, was in danger of being lost for all time. The reels were mostly of acetate stock that was not stored under anything like ideal conditions and was slowly decaying or being attacked by fungus and microbes.

“You can smell vinegar when you open the cans, which is one of the byproducts of the decomposition process of these films,” says Spriggs. “We know that these films are on the brink of decomposing to the point where they’ll become useless. The data that we’re collecting now must be preserved in a digital form because no matter how well you treat the films, no matter how well you preserve or store them, they will decompose. They’re made out of organic material, and organic material decomposes. So this is it. We got to this project just in time to save the data.”

You can view a number of the films at the second link above. I have embedded below the fold just one, from Operation Teapot in 1955. This was a series of 14 tests in Nevada. In this particular video the explosion occurs in the air, and you can sense the incredible force of the explosion when the shock wave hits the ground and bounces back, producing the mushroom cloud. Not much would have survived that impact.
» Read more