The Solar Death Ray

Skyscrapers with curved glass look really cool, but they can hide a dangerous feature- solar convergence, also known as the solar death ray. Any kid who ever tried to start a fire with a magnifying glass understands that bending the sun's rays into one spot magnifies the heat. This famously happened with two skyscrapers, Vdara Hotel & Spa in Las Vegas, and the skyscraper at 20 Fenchurch Street in London. Both have concave glass that converge sunbeams into deadly spots that vary depending on the position of the sun. The confounding part of the story is that both buildings were designed by the same architect, Rafael Viñoly. This video is only eight minutes long; the rest is an ad. (via Digg)