Astronomers have detected extreme, never-before-seen behavior from a rare kind of pulsar and stumbled on a surprising link to one of astronomy’s biggest current mysteries. Using 174 hours of radio observations, researchers detected PSR J1227-4853, a rapidly spinning neutron star known as a “transitional millisecond pulsar,” which unleashes hundreds of ultrashort, ultrapowerful “giant pulses.” Their paper was published in The Astrophysical Journal on July 31.

Neutron stars that rapidly rotate, completing one rotation in less than about 30 milliseconds, are called millisecond pulsars (MSPs). Among them is a rare class of neutron stars called transitional millisecond pulsars that swing between two different observational states: an accretion-powered state in a low-mass X-ray binary system and a radio-powered millisecond pulsar state. So far, only three transitional MSPs have been confirmed to exhibit this switching behavior.

In this study, Saptarshi Sarkar of the National Center for Radio Astrophysics in India and colleagues studied the third of these confirmed systems, PSR J1227−4853. Discovered in 2014 using the Giant Metrewave Radio Telescope (GMRT), it completes one rotation every 1.69 milliseconds.