Gamma-ray astronomy

observational astronomy performed at less than 10 nm wavelengths

thumb|300px|MAGIC (telescope)|MAGIC, a Cherenkov telescope in operation on the Canary island of [[La Palma. On foggy nights, the lasers that are used to focus the mirrors can be seen.]] IACT (imaging atmospheric [or air] Cherenkov telescope [or technique]) is a device or method to detect very-high-energy gamma ray photons in the photon energy range of 50 GeV to 50 TeV.