Questions for ‘Newfound gravitational waves may be from the biggest black holes in the universe’
![An illustration of a pulsar.](https://www.snexplores.org/wp-content/uploads/2023/06/062823_nanograv_feat-1030x580.jpg)
Dead stars called pulsars (illustrated) emit beams of radio waves. As pulsars spin, their beams of radio waves sweep past Earth like clockwork. Gravitational waves from supermassive black-hole pairs (upper left) are thought to ripple the fabric of spacetime, subtly altering the pulsars’ timing.
Aurore Simonnet/Sonoma State University, NANOGrav