When black holes collide, the ensuing cosmic drama was assumed to play out under the cloak of darkness, given that both objects are invisible. But now astronomers believe they have made the first optical observations of such a merger, marked by a blaze of light a trillion times brighter than the sun.
In high-energy particle collisions we study the smallest known constituents of matter. According to our best knowledge of physics, these constituents have mass only because of the way they interact with a unique quantity which permeates all of space. This quantity, like practically everything else in the strange world of the very small, is a quantum field.
NASA has shortlisted four proposals for its next astrophysics missions, due for launch in 2025. The agency has funding to fly two of them, and the four will now each receive funds for a nine-month period of technical study. The two missions will be chosen next year.