Gravitational waves & future space observatory

Gravitational waves: Tests begin for future space observatory

Image caption Artist’s impression: Lisa Pathfinder is stationed more than a million km in the direction of the Sun The formal test programme begins this week on the technologies required to detect gravitational waves in space. Europe’s Lisa Pathfinder (LPF) probe will engage in a series of experiments roughly 1.5 million km from Earth. The project has heightened interest, of course, because of the first sampling of the “cosmic ripples” made by ground-based detectors last September A successful demo for LPF would pave the way for a fully operational orbiting observatory in the 2030s. This would likely be known simply as Lisa – the Laser Interferometer Space Antenna. “It’s a wonderful time right now,” said Paul McNamara, the European Space Agency’s project scientist on Lisa Pathfinder. “I’ve spent my entire career in this endeavour, and for years we were told – even ridiculed in some cases – that gravitational waves don’t exist, or that we’d never find them. “Well, now we have found them, and we’re about to take the next big, big step towards building a mission that could detect them in space,” he told BBC News. The Earth-bound laser interferometers sited at the Advanced Ligo facilities in the US are sensitive to the gravitational waves generated in “smaller” cosmic events. Back in September, they observed the signal produced at the moment two black holes, each about 30 times the mass of our Sun, whirled around one another and merged. A space-based laser interferometer would chase much more massive targets – the monster black holes, millions of times the mass of our Sun, that coalesce when galaxies collide, for example. It is possible, however, that an orbiting observatory might also see Ligo’s lesser events – just at a different stage of their evolution. One back-of-the-envelope calculation has suggested […]