The mysterious spikes on a nuclear explosion

Above is a picture of a nuclear explosion approximately one millisecond after it has begun. This picture was taken in Nevada in 1952, and you can clearly see the mysterious spikes, or strands, that hang from the bottom of the explosion. These are the results of what scientists ended up calling the Rope Trick Effect.

In the late 1940s and throughout the 1950s, scientists were testing out nuclear bombs in a lot of places - including just a few miles from Las Vegas and in the sky above Hawaii. Badly placed though they might be, the drive to understand the effects of a nuclear bomb was perfectly understandable. As camera technology got better, it was possible to photograph more and more of the explosion. By 1952, people were able to snap a picture only milliseconds after a bomb went off; when they did, they noticed the strange spikes protruding from the bottom of the explosion, seemingly radiating towards the ground.

The mysterious spikes on a nuclear explosionS

The mystery was short-lived. Doctor John Malik, who investigated the phenomenon, noticed that the spikes hanging from the explosion coincided in position and direction with the cables on the tower that the bomb was placed on. In the top photograph, you can see it as a faint ladder-like structure below the explosion. The metal cords were tied at the base of the platform and flared out to secure it to the ground.

The idea needed to be tested, and Malik tried out a few things in the next sequence of explosions. He tried painting the cords black, or with dark paint, and then with highly reflective paint. He even had them covered with aluminum foil. In each photograph, the cables seemed to appear as a negative. When painted black, they shone white in the picture. When covered with reflective aluminum, or painted a light shade, they went dark in the photo.

Dark shades absorb light and heat more than light shades. When the bomb went off, it reached temperatures of 20,000 Kelvins, and the heat radiated to the metal cables. If they were dark, they absorbed the heat readily and vaporized — giving off a bright white light. If they were light-colored, or covered in reflective foil, they did not absorb heat as easily and remained dark. Because it was nothing more than a shining length of cord, Malik called the spikes that radiated from the nuclear explosions the Rope Trick Effect.

Image: The Nuclear Weapon Archive and The Atlantic.