A spacecraft traveling at 99 percent the speed of light toward Alpha Centauri would cross 4.3 light-years in what feels like ...

Astronomers have identified the birth of a magnetar, a hyper-magnetized neutron star, by detecting a subtle warping of space-time predicted by Einstein’s general relativity. The discovery came from ...

Editor's note: Scientists said today that after more than a half-century search, they have finally detected gravitational waves — the ripples in the fabric of space-time that Albert Einstein predicted ...