New insights into the inner structure of rapidly-rotating neutron stars have been gleaned by astronomers in Australia and Canada, who have studied the time evolution of a glitch – a sudden increase in the rate of stellar rotation. Their observations of the Vela pulsar suggest that glitches could be governed by interactions between three different rotating regions of the neutron star.
A pulsar is a spinning neutron star that broadcasts a lighthouse-like beacon of electromagnetic pulses at a constant frequency. Occasionally, however, the frequency of some pulsars can increase slightly in a process that astronomers call a glitch.
Vela is a pulsar that is about 1000 light-years from Earth and emits a bright beacon of radio waves. It spins at about 11 Hz and undergoes a glitch about once every three years, speeding-up by about 10-5 Hz.The neutron star has a radius of just 20 km yet has a mass greater than that of the Sun. It is made of neutron-rich matter that is tightly packed at densities on par with that of an atomic nucleus.
Astrophysicists have a poor understanding of the interior structure of neutron stars, which is why they are keen on understanding why pulsar ...