The European Space Agency successfully launched the LISA Pathfinder, a spacecraft designed to demonstrate technology for observing gravitational waves in space. The launch took place at Europe’s spaceport in Kourou, French Guiana on a Vega rocket, at 4:04 GMT on December 3, (10:04 pm EST Dec 2), 2015. Gravitational waves are ripples in the fabric of spacetime, which were predicted by Albert Einstein in his General Theory of Relativity. So far, because they are extremely tiny and incredibly faint, gravitational waves have proved to be elusive. The technology needed to detect them is highly sensitive and therefore has been difficult...