Most distant blazar is a high-energy astrophysics puzzle

(Phys.org) —Blazars are the brightest of active galactic nuclei, and many emit very high-energy gamma rays. New observations of the blazar known as PKS 1424+240 show that it is the most distant known source of very high-energy ...

Astronomers measure nearby Universe's 'cosmic fog'

Researchers from the Laboratoire Leprince-Ringuet (CNRS/École Polytechnique) have carried out the first measurement of the intensity of the diffuse extragalactic background light in the nearby Universe, a fog of photons ...

Backgrounds

You’ve probably heard of the cosmic microwave background, but it doesn’t stop there. The as-yet-undetectable cosmic neutrino background is out there waiting to give us a view into the first seconds after the Big ...