An experiment on the side of an extinct volcano in Mexico involving gamma rays is helping scientists answer a fundamental question in physics: Is the speed of light the same throughout the universe?

Schematics of the all-optical nonlinear Compton scattering experiment showing laser-driven electron acceleration, electron-laser collision, and Compton scattering to produce gamma rays. In a ...

sources can be uncertain by as much as a degree so making it difficult to identify their origin. Two of the newly discovered pulsars have positions which coincide within the positional uncertainties ...

Ancient Greeks imagined that everything in the natural world came from their goddess Physis; her name is the source of the word physics. Present-day nuclear physicists at the Department of Energy’s ...

A NASA-funded scientist has produced a new type of picture of the Earth from space, which complements the familiar image of our “blue marble”. This new picture is the first detailed image of our ...

Caption: The Crab Nebula. Photo courtesy of NASA. Beginning Sunday, September 18, 2011 at NASA’s launch facility in Fort Sumner, New Mexico, space scientists from the University of New Hampshire will ...

The Milky Way glows with a gamma ray haze, with energies vastly exceeding anything physicists can produce on Earth, according to a new paper. Gamma rays detected in the study, to be published in ...

For more than a decade, NASA’s Fermi Gamma-ray Space Telescope has quietly mapped the high-energy sky, searching for subtle patterns in the cosmic glow. Now a new analysis of its data points to a ...

The Universe is filled with energetic particles, such as X rays, gamma rays, and neutrinos. However, most of the high-energy cosmic particles' origins remain unexplained. The Universe is filled with ...