A Tour of RCW 103

Narrator (April Hobart, CXC): When stars have more than about 8 times as much mass as the Sun, they end their lives in a spectacular explosion called a supernova. The outer layers of the star are hurtled out into space at millions of miles per hour, leaving a debris field of gas and dust. Where the star once was located, a small, incredibly dense object called a neutron star is often found. While only 10 miles or so across, the tightly packed neutrons in such a star contain more mass than the entire Sun.

The supernova remnant called RCW 103 is a by-product of one of these explosions and the neutron star it left behind, known as 1E 1613, is proving to be particularly interesting. For years, astronomers have known that 1E 1613 shows a regular brightening and dimming in its X-rays that repeats about every six and a half hours. It could be a neutron star that is rotating much more slowly than other neutron stars, or it could be a faster-spinning neutron star that has a normal star as a companion.

New data from four high-energy telescopes, Chandra, Swift, NuSTAR and XMM-Newton, have shown that the unusually slow spin is the correct explanation and that.1E 1613 has the properties of a magnetar. Magnetars are neutron stars that possess enormously powerful magnetic fields, trillions of times greater than that on the Sun.

While it is still unclear why 1E 1613 is spinning so slowly, scientists do have some ideas. One leading scenario is that debris from the exploded star has fallen back onto magnetic field lines around the spinning neutron star, causing it to spin more slowly with time. Searches are currently being made for other very slowly spinning magnetars to study this idea in more detail.