Astronomers have identified a peculiar neutron star, designated ASKAP J1839-0756, located 13,000 light-years away. This discovery, made using the ASKAP radio telescope, suggests the existence of a pulsar variant previously unseen, potentially reshaping our understanding of these dense remnants of massive stars.
Neutron stars form after massive stars explode in supernovae, resulting in extremely dense objects. Pulsars are neutron stars that rotate rapidly and emit radio waves from their magnetic poles. Typically, pulsars spin at over one rotation per second, aligning with the frequency of emitted radio pulses.
Recent findings have revealed compact objects emitting radio waves at significantly lower frequencies, raising questions among astronomers. These long-period radio transients, which emit signals at intervals exceeding one rotation per minute, defy established expectations. Last year, a similar object with a rotation period of 54 minutes was discovered. The newly identified ASKAP J1839-0756 rotates at an unprecedented rate of one rotation every 6.45 hours.
Initially thought to be a white dwarf, further analysis indicated that this object is too large for that classification. Subsequently, researchers considered it a magnetar, a neutron star with the strongest magnetic field in the universe. While a magnetar with a 6.67-hour rotation period has been previously identified, it only emits X-rays, not radio waves.
If confirmed as a solitary magnetar, ASKAP J1839-0756 would be the first of its kind to emit radio waves while exhibiting such a slow rotation. Researchers assert that this discovery fundamentally alters existing perceptions of neutron stars and necessitates a reevaluation of the theory that pulsars cease radio emissions when their rotation slows.