In Manchester, England, a city more famous for its soccer team than its museums, the Manchester Museum is getting a lot of press this week. It released time-lapse footage of an ancient Egyptian statue slowly rotating in its sealed case. The statue, of an official named Neb-senu, dates back to around 1,800 BC, and was given to the museum 80 years ago. In all those decades, this is the first time that anyone has seen it spin.

Tim Manley, head of marketing and communications at the museum, told the Manchester Evening News: “We’re sure there’s a logical explanation, we’re just not quite sure what it is yet.”

Museum curator Campbell Price first noticed the spinning statue in February and wrote a blog post about it, in which he said: “It is just possible that someone is playing a trick. But I doubt it.” Aside from the various supernatural theories that are inevitable when talking about grave goods from Egypt, some have suggested that it is moving because of the foot traffic of museum visitors, traffic outside, or the differential friction between the glass and the base of the statue. Some have even suggested that it might be magnetism, because the statue is carved of the rock steatite, or soapstone, which contains traces of magnetite.

In the time-lapse footage, the statue only appears to move during the day, and only moves 180 degrees. None of the other statues in the case move, just this one. LiveScience checked in with Paul Doherty, a scientist at the Exploratorium in San Frnasico, who has a theory of his own:

“ believes the statue’s movement isn’t caused by any supernatural force, but by something quite ordinary: vibrational stick-slip friction, sometimes called stick-slip vibration. As Doherty told LiveScience, if the glass shelf on which the statue rests vibrates even slightly, “the vibrating glass moves the statue in the same direction,” causing it to turn around. An everyday example can occur when someone uses an electric blender on a kitchen countertop: The vibration of the blender can cause a nearby coffee cup to “walk” across the countertop. But why would the statue stop moving after turning 180 degrees? Doherty believes the statue stops turning because it’s asymmetrically weighted: “One side of the statue has more weight than the other side.” After turning around on the shelf, the statue’s uneven bottom reaches a more stable position and stops turning.”

Whatever the reason—physics, ghosts or a trick played on the public—it’s been great publicity for the museum. The museum told the local press that they’d already received “hundreds more visitors” than usual.

The Sun had a description of the statuette written by Price:

This statuette is of an official — probably with priestly duties — and is made from serpentine, a hard stone. It shows a man, standing with his left foot forward wearing a shoulder-length wig and a knee-length kilt. Hieroglyphs on the back of the figure spell out a prayer for offerings (“bread, beer and beef”) for the spirit of the man. The reading of his name is unclear – but may be pronounced “Neb-senu”. It was donated to the museum by Annie Barlow, of Bolton, in 1933.

More from Smithsonian.com:

Digging up Egypt’s Treasures

Egyptian Mummification Rituals Uncovered at Natural History

How One Mummy Came to the Smithsonian