Astronomers have recorded the first direct evidence of a magnetar forming during a superluminous supernova. The discovery came from observations of SN 2024afav, which exploded roughly one billion light-years from Earth.
The supernova was discovered in December 2024. A global network of telescopes monitored it for more than 200 days, revealing repeated brightness fluctuations that sped up over time.
Researchers attributed the pattern to a newborn magnetar whose tilted accretion disk wobbled due to Lense-Thirring precession, an effect predicted by general relativity. The neutron star is estimated to spin once every 4.2 milliseconds with a magnetic field 300 trillion times stronger than Earth's.
"This is definitive evidence for a magnetar forming as the result of a superluminous supernova core collapse," said Alex Filippenko of UC Berkeley.
The findings were published in the journal Nature. Scientists noted that magnetars may not power every superluminous supernova and that additional examples are expected from future surveys.