Neutron stars come in many forms and are consistently amazing in their power and complexity. We now turn from pulsars to magnetars and look at the activities of SGR 1830-0645, which is nicknamed SGR 1830 for short. 

Located about 13,000 light-years away in the direction of the constellation Scutum, this star gave off a burst of X-rays that were spotted by the Swift telescope on October 10, 2020. Follow-up observations with NASA’s Neutron star Interior Composition Explorer – or NICER – on the International Space Station (ISS) showed the system initially had three different hot spots that rotated through its view as the dead star rotated every 10.4 seconds. Over the next few weeks, those spots were seen to migrate closer and closer together.

According to NASA’s release on these observations: The results favor a model where the spots form and move as a result of crustal motion, in much the same way as the motion of tectonic plates on Earth drives seismic activity. … The team thinks these observations reveal a single active region where the crust has become partially molten, slowly deforming under magnetic stress. The three moving hot spots likely represent locations where coronal loops – similar to the bright, glowing arcs of plasma seen on the Sun – connect to the surface. The interplay between the loops and crustal motion drives the drifting and merging behavior.

More Information

NASA Goddard press release

“Pulse Peak Migration during the Outburst Decay of the Magnetar SGR 1830-0645: Crustal Motion and Magnetospheric Untwisting,” George Younes et al., 2022 January 13, The Astrophysical Journal Letters