Astronomers have detected the most distant very-high-energy blazar ever observed, capturing gamma rays that traveled nearly 8 billion light-years before reaching Earth. The discovery, reported in ...

A new observatory is set to detect sources of cosmic rays, dark matter and other relics of the Big Bang in a few years' time.

In a single experiment, physicists have measured the "excess" emission of high-energy gamma rays from more than a dozen heavy, unstable atomic nuclei. Mapping the gamma-ray emissions of so many ...