NASA's IXPE Detects Vacuum Birefringence in Magnetar 1E 1547‑5408

NASA’s Imaging X‑ray Polarimetry Explorer (IXPE) together with the NICER X‑ray instrument and Australia’s Murriyang (Parkes) radio telescope observed the magnetar 1E 1547‑5408 for more than 140 hours. The coordinated measurements revealed X‑ray polarization three times higher than in similar sources and a consistent alignment with the star’s magnetic field.

These findings match the long‑standing quantum‑electrodynamics prediction of vacuum birefringence, first proposed in 1936. Researchers, including Dr. Marcus Lower of Swinburne University, say the extreme magnetic field of the magnetar—over a trillion times stronger than any laboratory magnet—acts like a prism that polarizes light, providing the first direct evidence of the effect.

The result, published in Nature, confirms a 90‑year‑old theory and demonstrates the power of combined space‑based X‑ray and ground‑based radio observations for probing extreme physics.