 With our eyes, we see only a tiny fraction of the light in the universe. To see more, we need instruments that can see light we can't. Like gamma rays, the result of subatomic particles accelerated in violent places like stellar explosions or the jets discharged by supermassive black holes. Nothing generated on Earth comes close to the energy of the highest energy gamma rays. They can fly through the universe without getting scrambled by magnetic fields. We can't see them coming, but they travel directly towards us. But they never actually make it to the Earth's surface. They interact with the atmosphere, producing cascades of high-energy subatomic particles. These energetic particles move faster than the light in the air. And like a plane creates a sonic boom, they create a photonic boom. It's called Cherenkov light. It's blue, and it's spectacular. But this happens in a billionth of a second, so we need powerful telescopes to see it. Like CTA, two arrays of telescopes, one in the Atacama Desert in Chile and another atop the Spanish island of La Palma. The Cherenkov light will flash and disappear. This faint glimmer can be collected by the telescope's mirrors and reflected into cameras, capturing a billion frames per second. The light will be captured by sensors able to detect a single photon and turn it into digital data. Data centers will store and process the information, so scientists can work with it. The telescopes are positioned to increase our chances of detecting Cherenkov light. More telescopes gives us more information. By layering these images, we can estimate the energy of the gamma ray and pinpoint its direction in the sky. The data will be accessible to anyone, anywhere, so the discoveries are limitless. Precious information, carried by invisible gamma rays, allowing us to see into the most unknown parts of the universe to help unlock its secrets.