Guest Author - Lea Terry

A recently discovered neutron star has set a new speed record, rotating at 1,122 times per second. Not only is that faster than the previous record for a neutron star--760 times per second--it’s also faster than a black hole observed in 2006, which rotated at 950 times per second. So how does this discovery compare to what we’ve already observed about neutron stars?

The concept was first proposed in 1932, when James Chadwick discovered the neutron particle. (He won the 1935 Nobel Prize in Physics for his discovery.) In 1933, Walter Baade and Fritz Zwicky proposed the existence of a neutron star--a star formed from the gravitational collapse of a massive star. The material of the original star collapses into an incredibly dense body--second only to the density of a black hole. The neutron star rotates rapidly, and because it is so compact, it has an exceptionally high surface gravity.

After the discovery of the neutron star, the next major clue about the nature of these celestial objects was observed in 1967, when Jocelyn Bell Burnell and Antony Hewish discovered radio pulses being emitted from a pulsar. These pulses were later suggested to be coming from a solitary, rotating neutron star (called a rotating pulsar). Then, in 1971, Riccardo Giacconi, Herbert Gursky, Ed Kellogg, R. Levinson, E. Schreier, and H. Tananbaum observed 4.8 second pulsations coming from the constellation Centaurus. They believed these pulsations to be coming from a rotating hot neutron star.

This latest discovery about neutrons is significant, because it brings scientists a step closer to understanding the structure of a neutron. All stars have a speed limit--if they rotate too quickly, they will break apart. Because scientists still don’t know the exact structure of a neutron, they had no way of knowing how fast one could rotate before breaking up. However, if astronomers can observe more neutrons with a similar rate of rotation, it will allow them to rule out some of the possible structures.