Astronomers Make New Discoveries About Nearest Millisecond Pulsar

About the episode

Like a kind of wild lighthouse, it beams a beam of radio and X-rays toward Earth every 5.75 milliseconds: the pulsar PSR J0437. A spinning neutron star, it’s 150 light-years away.

This neutron star is the closest known millisecond pulsar, rotating on its axis 174 times per second and accompanied by a white dwarf star.

It is also, partly because it is so close, the brightest of its kind. And in terms of timing, it is also a more stable clock than the atomic clocks we make.

We now know a lot about this pulsar, thanks to intensive calculations performed by a Dutch supercomputer. The researchers combined this with measurements made by the NICER X-ray telescope on board the International Space Station. This made it possible to calculate the star’s radius (11.4 kilometers) and determine the temperature distribution of the magnetic poles.

These two poles did not seem to be exactly opposites. They had hoped beforehand that they would be able to confirm this, but they were pleasantly surprised that it actually worked.

Thanks to the research, they were also able to say something about existing theories that tell us something about the maximum mass of neutron stars. They now think that it must be lower than expected. And the researchers say this agrees well with research into gravitational waves.

The researchers hope to get more data from the NICER X-ray telescope in the near future, both from this pulsar and from others. Ultimately, the researchers want to be able to predict for each neutron star what the star is made of and what forces are at play between the particles.

Read more about the research here: The nearest millisecond pulsar has a radius of 11.4 kilometers and a mass 1.4 times that of the Sun.