I agree that's a big rock. I'm also careful to not camp where rocks can fall. I was camped out at Dalton Wells one night, right under the quarry but far enough out to not be in danger, and I heard what sounded like a rifle shot - looked up to see a big chunk of rock coming down. I have a photo of it falling as my camera was already in my hand (taking photos of the dogs). You can see where it came down if you look, as the cliff there's a lighter color.
When living in Moab, I witnessed two really big rockfalls coming off the rim with their huge clouds of dust. I could hear them from clear across the valley. I came within seconds of having my car smashed when I lived in the Roaring Fork Valley (Colorado). The car behind me took the hit, but nobody was hurt. Rockfall is very common there.
