© NASA/Fermi Gamma-ray Space Telescope.
The Fermi Gamma-ray Space Telescope, launched in 2008, looks at the most energetic photons in the universe. These high-energy photons are expected to originate from exotic objects such as supermassive black holes. Gamma rays are also produced when electrons and their antimatter counterpart, positrons, annihilate. In some scenarios, WIMPs will annihilate into electrons and positrons, which in turn annihilate into gamma rays. Excess gamma rays in regions of space expected to contain a high concentration of dark matter would be a strong suggestion that the dark matter is made of WIMPs. (Unit: 10)