A physicist at the University of Wisconsin-Madison has released an app that transforms that ordinary smartphone in your pocket into a device that detects elusive cosmic rays. And it wasn't even that hard: "It was just one of those hobbies that happened to work out," said assistant professor Justin Vandenbroucke in a news release. Normally these mysterious rays, the origins of which are as yet unknown, arrive from deep space and strike silicon sensors in physics labs, producing a charge, much like how ordinary light strikes a digital camera. And it turns out your phone's sensor is just as capable of detecting those rays as these special setups.
Simply cover up the lens with duct tape and let the app watch the sensor for cosmic rays, which pass through physical obstacles with ease. You won't be competing with real lab gear, but Vandenbrouke hopes it will help educate people about the ubiquitous nature of cosmic radiation, and could perhaps evolve into a "citizen science" project with enough data. The app is free but it's not in the Play Store; you can download and install it from the project's site.