A ground-penetrating nuclear bomb has been used for the first time in six years on US soil—but, fortunately, without its nuclear warhead in place.
These images are the result of new tests by Sandia National Laboratories of the B61-11 nuclear bomb. Picked from a stockpile of US weaponry, it was fitted with sensors, chilled to simulate the low temperatures it would experience when strapped to an aircraft, then driven into a concrete target.
The odd patterning and grainy quality to the picture is due to the image being composite of three images captured by high-speed video. "The square speckles provide a random pattern used in digital image correlation algorithms to calculate test unit motion in 3-D using special equipment" as explained by Sandia.
It's the first such test by Sandia since 2008. The reason for the lull? The test rig used to fire the bomb into the ground uses a high-power rocket sled, which unexpectedly fired during the last test, severely injuring one employee. Since then, the testing procedures have been given an overhaul. [Sandia National Laboratories via New Scientist]