Magnetic Levitation
This globe floats in mid-air with nothing touching it. A magnet inside it is pulled up by an electromagnet hidden in the top of the C-shaped arm, and a small sensor and circuit keep it there.
Ask your guide to rotate the globe and it will continue rotating, as there is very little friction to stop it.
Additional Information
Magnets alone can’t hold something still in mid-air: it always flips over, slides away or snaps to the magnet (a rule called Earnshaw’s theorem). So this globe is held by a magnet that is constantly adjusted. A sensor measures the gap many times a second. If the globe drops a little, the electromagnet pulls harder; if it rises, the pull eases. Unplug it and the globe falls.
The same magnetic levitation principle powers maglev trains, which float above their tracks and can reach speeds over 600 km/h with no wheels rubbing on rails.
Superconducting magnets can also achieve stable levitation without any active electronics, through an effect called flux pinning.