Marcia Bartusiak— Gamma rays from deep space were discovered by accident in the early 1970s. A group of United States satellites called Vela (“watch” or “vigil” in Spanish) had been put into orbit to make sure nations around the world were complying with the 1963 nuclear test ban treaty. Sifting
Marcia Bartusiak— Early last year, the field of astrophysics announced one of its biggest discoveries. A cosmic phenomenon that Albert Einstein had predicted a century earlier was at last detected directly. Two massive black holes collided, their spectacular merger generating huge ripples—gravitational waves—in the very fabric of space-time. After spreading