Take away all the known sources of gamma rays in the universe, and you might be left with the above picture – something a new NASA probe could soon see. If it does, astronomers will be elated because they will have finally “seen” dark matter.
Our galaxy is thought to be surrounded by a halo of dark matter, but what it consists of is unclear. One of the favoured candidates is a particle called the neutralino. If neutralinos exist, they should interact with each other to produce gamma rays.
In December, NASA will launch the Gamma-ray Large Area Space Telescope (GLAST),…
