In February 2016, Albert Einstein made history, again. That’s when physicists announced they’d finally observed what the great scientist’s theories had predicted 100 years earlier: gravitational waves.
The first confirmed sighting of gravitational waves — distortions of space-time, literally ripples in the fabric of the universe — was a tremendous feat, earning Nobel Prizes for the key developers of the Laser Interferometer Gravitational-wave Observatory (LIGO). The waves’ ultimate source was just as fantastic as the engineering that went into detecting them: two black holes smashing together, their enormous gravities sending undulations throughout the cosmos.
This achievement, the culmination of a multidecade-long effort, was justifiably celebrated. But while it resolved the long-standing issue of whether gravitational waves existed, it also marked a starting point for a whole new journey.
Before, astronomy had been based solely on studies of electromagnetic radiation and exotic particles like neutrinos and cosmic rays. But the tiny ...
