Scientists have announced the first detection of gravitational waves, a finding that will give astronomers an entirely new window to the universe. But how are these waves observed and why have we never seen them before?
Gravitational waves are ripples in the space-time continuum first predicted by Albert Einstein 100 years ago.
They can be produced in many ways, but their effect on time and space is so infinitesimal that it requires the motion of massive and dense objects like black holes and neutron stars to create gravitational waves strong enough to be observed by instruments on Earth.
Scientists say the