One of the best-known pulsars, in the Crab Nebula about 6,000 light years from Earth, has experienced six glitches since its discovery in 1968. We know about more than 700 radio pulsars. And of these 20, at least three behave like the Crab pulsar, where after a glitch you see them spin down faster than they were spinning down before. A neutron star's magnetic field plays a key role in the process. It was already known that a neutron star constantly loses rotational energy to its misaligned magnetic field, which then radiates that energy into space.
Astronomers see the emitted radio waves as radio pulses.
Franco and her co-authors have modeled stresses in the solid outer crust of a neutron star that would quantitatively explain the more rapid rotational slowdowns that follow glitches. The faster an object such as the Earth or a neutron star rotates, the more stress the sphere builds as it spins down. This energy cracks the neutron star at the equator, allowing matter to move from the equator toward the magnetic poles. Little mountains form, throwing the distribution of matter at the surface out of balance, causing the star to wobble. This wobble increases the difference between the star's rotational axis and the axis of its magnetic field, which in turn increases the star's energy loss.