Did you hear the one in regards to the star that died twice? In 2014, astronomers noticed the explosion of the Refsdal supernova. Then, 360 days later, it went bang once more.

This weird sequence of occasions was right down to a phenomenon referred to as gravitational lensing, by which large objects warp the material of area sufficient to trigger gentle to bend. The trail of the flash from the supernova was modified on this approach on its journey to us, in order that parts of it took completely different routes and arrived at completely different instances – virtually a yr aside on this excessive case.

As that story reveals, gravitational lensing has been round for some time, however now it’s about to enter a compelling new chapter. Scientists understand it isn’t simply gentle that may be lensed, however gravitational waves too. It’s a mind-bending idea: ripples in space-time themselves being distorted by the curvature of area. Additionally it is a deeply essential phenomenon that would illuminate the key interiors of neutron stars, settle a thriller in regards to the energy of darkish power and check gravity itself extra keenly than ever. And right here is the most effective half: we could also be on the cusp of recognizing our first lensed gravitational wave.

Nobody is underneath any illusions that this might be something aside from fiendishly troublesome. Nonetheless, there’s a sense it can occur eventually – and there are tips we are able to pull to expedite the invention. “It’s thrilling, and it’s going to occur,” says Simon Birrer at Stony Brook College in New York. “There’s…