https://www.newscientist.com/article/2380451-gravitational-waves-produce-a-background-hum-across-the-whole-universe/ https://www.newscientist.com/article/238045

https://www.newscientist.com/article/2380451-gravitational-waves-produce-a-background-hum-across-the-whole-universe/ https://www.newscientist.com/article/2380451-gravitational-w... "To find this mysterious hum, astronomers have been tracking rapidly rotating neutron stars called pulsars that blast out light with extreme regularity. By looking at different pulsars across the Milky Way, astronomers can effectively use them as a galaxy-sized gravitational-wave detector called a pulsar timing array."