posted on Jun, 26 2013 @ 05:33 AM
I think this is at Manchester Museum? If that is Manchester UK, then the museum is on one of Manchesters busiest roads, Oxford Road.
Not only does Oxford Road handle a lot of heavy traffic (buses, wagons) which run 24/7, its also in the middle of Manchester University, with campus
buildings on both sides of the road. In fact the museum is part of the university. The traffic activity is highest during daylight hours, explaining
why it moves more during the day.
So the "vibration theory" has a lot of creedence, however, I have to ask why it stops moving after 180 degrees? If the movement was caused by
vibration, wouldn't it continue moving?
I think vibration is going to be the most likely explanation, but I would also offer "student prank" given its part of a massive
edit on 26/6/2013 by BMorris because: added my theory