Egyptian statue filmed inexplicably rotating

Super-natural effects are always caught with the worst cameras. It is very clear this statue is moving, inside its locked case, but why? Is it a simple effect of local vibration? Why hasn't it moved before?

Nature World News reports:

Campbell Price, the curator of the Manchester Museum's Egypt section, said that the statue, which has been in the museum's collection since 1933, has recently started to slowly turn in a perfect arc while in its glass enclosure.

"I noticed one day that it had turned around," Price said, according to the Daily Mail. "I thought it was strange because it is in a case and I am the only one who has a key. I put it back, but then the next day it had moved again."

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