At the most basic level, magnetars are neutron stars. When some of the larger stars in our universe run out of fuel for fusion in their cores, they collapse down until protons and electrons are no longer able to stay separated. Under the force of gravity, these particles combine, and in a flash of energy and particles, they transform into a dense sphere of neutrons. Only about 3000 neutron stars have so far been discovered, and of these, only 31 have turned out to be magnetars. With each newly found object, magnetars are proving themselves to be even weirder than previously thought.

That thirty-first magnetar was discovered March 12, 2020, by astronomers using the Swift space telescope. It was found thanks to a burst of X-rays it emitted. We discussed this object on our podcast last June. Initially, all we knew was this bursting system is only about 500 years old; It is perhaps the youngest magnetar ever found!

New research coming out in Astrophysical Journal Letters, by Harsha Blumer and Samar Safi-Harb, presents follow-up results that use a myriad of telescopes to peer at this system in just about every kind of light. From radio and infrared observations, they were able to find possible debris from the supernova that created this object, which has the catalog ID J1818.0-1607. If their match is correct, the neutron star is one of the fastest moving ever detected.

In the composite X-ray and infrared image you can see on our website, you can see this pulsar as a pink blob of X-rays. This light isn’t all coming from the tiny 21-mile-across star. What we’re seeing is a small point source surrounded by a diffuse halo of light being scattered by surrounding dust. This is like looking at a flashlight in the fog: the beam is brightest in the center, but the fog creates a diffuse halo. The radio observations also showcased the systematic pulsing of a pulsar that rotates every 1.4 seconds. 

Put together, this data shows us that magnetars can be ejected at wild velocities from the supernova they form in and may spin up to fabulous speeds during their collapse, like an ice skater drawing in her arms ever tighter and tighter while rotating. If the theory is correct, humans will be able to watch this young object slow down over time, and track its motion, but that may be research for another generation.

More Information

NASA press release 

“Chandra observations of the newly discovered magnetar Swift J1818.0-1607,” Harsha Blumer and Samar Safi-Harb, to be published in Astrophysical Journal Letters (preprint on arxiv.org)