Particle never before seen on Earth detected; it could come from a primordial black hole and the origin of the universe.

Solar physicists say they have found a key source of intense gamma rays unleashed when Earth's nearest star produces its most violent eruptions. In findings published in Nature Astronomy, scientists ...

There appear to be too many gamma rays coming from the sun. New higher-energy measurements reveal that this excess continues for a bit, then disappears — a cutoff that could help clarify what’s going ...