Photographer Ross Bernards says he was at the Utah site Friday night taking pictures when four men appeared with a wheelbarrow, then pushed over and quickly dismantled the monolith. Were they the same people who put it up? Not clear. Bernards says he and his companions didn't try to stop the men. "As they walked off with the pieces, one of them said, 'Leave no trace,'" Bernards says.
You can read Bernards' own account of this on Instagram. He writes that the men were right to remove the object because it was beginning to attract lots of visitors who weren't respecting the delicate environment. "This is why you don't leave trash in the desert," he quotes one of the men as saying.
Reuters reports that the similar-looking object that turned up in a remote area of Romania vanished on Tuesday. Now all that remains is just a small hole covered by rocky soil.
So we're sure it's not aliens at this point (sorry, Mike!) but viral marketing stunt is still a possibility!