Prior to sealing up the chamber and pumping the vacuum system down, a LIGO optics technician inspects one of LIGO’s core optics (mirrors) by illuminating its surface with light at a glancing angle. It is critical to LIGO's operation that there is no contamination on any of its optical surfaces. Credit: Matt Heintze/Caltech/MIT/LIGO Lab Update, 11 February: A hundred years after Einstein predicted them, gravitational waves from a cataclysmic event a billion years ago have been observed. For the first time, scientists have observed gravitational waves, ripples in the fabric of spacetime arriving at Earth from a cataclysmic event in the distant universe. This confirms a major prediction of Albert Einstein's 1915 general theory of relativity and opens an unprecedented new window to the cosmos. The discovery was announced on 11 February at a press conference in Washington, DC, hosted by the National Science Foundation, the primary funder of the Laser Interferom...