Peeling Scotch tape generates X-rays

Wild and weird. Peeling ordinary cellphane tape in a vacuum can generate enough triboluminescent X-rays to produce a film of a human finger:

"Researchers at the University of California, Los Angeles, have shown that simply peeling ordinary sticky tape in a vacuum can generate enough X-rays to take an image — of one of the scientists' own fingers (see videos).

'At some point we were a little bit scared,' says Juan Escobar, a member of the research team. But he and his co-workers soon realized that the X-rays were only emitted when the kit was used in a vacuum. 'We don't want to scare people from using Scotch tape in everyday life,' Escobar adds.

This kind of energy release — known as triboluminescence and seen in the form of light — occurs whenever a solid (often a crystal) is crushed, rubbed or scratched. It is a long-known, if somewhat mysterious, phenomenon, seen by Francis Bacon in 1605. He noticed that scratching a lump of sugar caused it to give off light."

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