Big Bang Light Reveals Minimum Lifetime of Photons

The notion of the speed of light as the cosmic speed limit is based on the assumption that particles of light, called photons, have no mass. But astrophysical observations cannot rule out the slim chance that photons do have a tiny bit of mass—a prospect with wide ramifications in physics. For instance, if photons weigh nothing at all, they would be completely stable and could theoretically last forever. But if they do have a little mass, they could eventually decay into lighter particles. 

SpaceX wins bid to launch Canadian radar satellites

Privately owned Space Exploration Technologies was selected to launch a trio of Canadian radar satellites aboard a single Falcon 9 rocket, the company announced on Tuesday.

The California-based firm, also known as SpaceX, already is flying NASA cargo to the International Space Station, a permanently staffed research outpost that flies about 250 miles above Earth.

NASA Astronaut Says Spacesuit Water Leak Was 'Scary Situation'

The mysterious leak that cut a spacewalk short two weeks ago was apparently as frightening as it looked to those of us watching on NASA TV.

On July 16, NASA astronaut Chris Cassidy and his European colleague Luca Parmitano hustled back inside the International Space Station after water began filling Parmitano's helmet,