Every second, the Earth is being struck by cosmic rays, high energy particles that slam into the atmosphere. Understanding where they come from and how they're generated could provide information about some of the most energetic processes in the Universe. But Earth's atmosphere protects us from them, ensuring that they don't make it to the surface. Instead, we have to look for the shower of photons and particles that the cosmic rays create when they hit the atmosphere.

Even large detectors, however, only capture a few traces of the high energy particles that reach the Earth, meaning that careful studies of their origin can take years, possibly even decades. So some researchers decided it might be possible to take advantage of a large population of non-specialized detectors that are pre-positioned all over the world: cell phone cameras.

The researchers from the University of California have drafted a paper in which they describe testing whether a smartphone camera can detect high energy photons and particles of the sort produced by cosmic rays. Testing with radioactive isotopes of radium, cobalt, and cesium showed that the detector easily picked up gamma rays (and you didn't even have to point the phones at the source!). They also put a phone inside a lead box and showed that they could detect high energy particles. Finally, they took a phone up on a commercial flight and were able to obtain a particle track across the detector.

With everything looking good, they made some software, called CRAYFIS, for cosmic rays found in smartphones (why they didn't add "and handhelds," I'm not sure). When your phone is inactive and plugged in for charging, CRAYFIS monitors the camera, looking for signs of high-energy items striking the detector. The authors calculate that if they can get 1,000 active cell phones within a square kilometer, they'll be able to detect nearly all of the high energy cosmic rays that strike the atmosphere above it despite the low efficiency of each individual detector.

All well and good, but it's not clear that this sort of adoption rate is likely. And in an ideal world, they want over 800 clusters of this power, which adds considerably to the challenge. Still, it's a creative use of the vast amount of imaging sensors that have been sent out into the world over the past several years.

You can visit the group's site and sign up to test the beta version. Android and iOS version are being developed.