This is one of the most jaw-dropping videos you're going to see this year. It shows the collapse of the Metrodome roof. The Minneapolis sports stadium is (quite appropriately) also known by its full name, The Hubert H. Humphrey Metrodome.
This actually marks the fifth time that the roof has collapsed or deflated. It's made of teflon-coated fiberglass fabric. It's held up by air pressure and was considered something of a marvel when it was built in 1982.