A Mysterious Neutron Star Shouldn’t Exist But It Does

Neutron star: a celestial object of very small radius (typically 18 miles/30 km) and very high density, composed predominantly of closely packed neutrons; thought to be formed form by the gravitational collapse of the remnant of a massive star after a supernova explosion, making it essentially a stellar corpse and too small to be a black hole.

 

Relativistic jet: beams of ionised matter accelerated close to the speed of light; associated with central black holes, galactic stellar black holes and neutron stars.

 

Rule of neutron stars and relativistic jets: relativistic jets do not come out of neutron stars with strong magnetic fields.

Until now.

According to their study published in the journal Nature, Astronomer Jakob van den Eijnden of the University of Amsterdam and his team of researchers observed a strange, unexpected and thought-to-be-impossible radio emission coming from Swift J0243.6+6124, a slow-spinning neutron star 24,000 light-years away from Earth in the constellation of Cassiopeia, discovered on October 3, 2017, with NASA's orbiting Neil Gehrels Swift Observatory. This neutron star is part of a binary system, feeding off of a much larger star. The neutron’s gravity pulled the material and gas away from the other star and formed a disc between them. When it got big enough, the neutron star’s gravity pulled the disc in and energy created converted into the relativistic jet detected by the Swift satellite.

Except that it’s impossible for a dense dead star to create relativistic jets. Well, now make that improbable. In an article in The Conversation, astronomer and study co-author James Miller-Jones says this event requires a new theory on neutrons and jets.

“Recent theoretical work has suggested that under certain circumstances it might be possible to launch jets from the extraction of the neutron star’s rotational energy. In our case, this could have been enabled by the high rate at which matter was falling inwards. It would also explain why the jets that we saw were about 100 times weaker than seen in other neutron stars with weaker magnetic fields.”

Still here? Is this a big deal? Nathalie Degenaar, University of Amsterdam astronomer and study co-author, thinks so.

"This discovery not only means we have to revise our ideas about jets from such systems, but also opens up exciting new areas of research."

In other words … more jobs for astronomers! James Miller-Jones agrees in ScienceAlert:

"Whatever the explanation, our result is a great example of how science works, with theories being developed, tested against observations and revised in light of new experimental results.”

Finally, a win for science! Crack open those science books, participate in science fairs, study your math and look at the stars. You too could be destined for an exciting career with good job potential in the field of astronomy.