Gravitational Waves Discovered: A New Window on the Universe

"Ladies and Gentlemen, we have detected gravitational waves. We did it." With those words, Dave Reitze, executive director of the U.S.-based Laser Interferometry Gravitational-Wave Observatory (LIGO), has opened a new window into the universe, and ushered in a new era in space science. Predicted over 100 years ago by Albert Einstein, gravitational waves are ripples in space-time. They travel in waves, like light does, but they aren't radiation. They are actual perturbations in the fabric of spac...