Scientists hear gravitational waves in space

Scientists have observed for the first time the faint ripples caused by the motion of black holes that are gently stretching and squeezing everything in the universe.

They reported Wednesday that they were able to “hear” what are called low-frequency gravitational waves — changes in the fabric of the universe that are created by huge objects moving around and colliding in space.

To find the waves, scientists pointed telescopes at dead stars called pulsars, which send out radio waves at a regular beat.

By noticing tiny changes in the ticking of these cosmic clocks, they could identify the gravitational waves passing through.