They have a camera that captures images at over a trillion times a second, fast enough to capture individual light particles traveling through space. I don't think I have to explain how INCREDIBLY -blam!-ING AMAZING THIS IS. Photographers may ask how you can get enough light when the exposure is less than a trillionth of a second. Basically they take multiple pictures of the exact same frame over and over again until enough light is captured to create an image. Pretty amazing stuff.