On 14 September 2015, the universe’s gravitational waves were observed for the very first time. The waves, which were predicted by Albert Einstein a hundred years ago, came from a collision between two black holes. It took 1.3 billion years for the waves to arrive at the LIGO detector in the USA.
. . . The LIGO project’s achievement was using a pair of gigantic laser interferometers to measure a change thousands of times smaller than an atomic nucleus, as the gravitational wave passed the Earth.
«The 2017 Nobel Prize in Physics – Press Release», in Nobelprize.org ; Stockholm : Nobel Media AB, 3 october 2017 (excerpt La Litera información)