Astronomers based in Hawaii have found a way of peering through the clouds of dust that surround supermassive black holes: they simply place sunglasses over their telescope lens. Or, to be more accurate, they fit a polarising filter in the UK Infrared Telescope that sits atop the now thankfully dormant Mauna Kea volcano.
As well as reducing brightness, polarising sunglasses only let through light with a very narrow range of wave orientations. This serves to remove randomly-oriented photons scattered off water surfaces and clouds, and the glare from car windscreens. With polarising filters fishermen can see their prey swimming about in a river, and astronomers now survey the heart of a galaxy, free of the usual dusty haze.