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Nasa detects 'unusual' infrared light from mysterious neutron star

A neutron star in the depths of space has been detected beaming out abnormally bright infrared radiation, in a development that has left astronomers perplexed.

The distant phenomenon was spotted using Nasa’s Hubble Space Telescope, and the team behind the discovery hope it will help them understand the development of these super-dense stars.

Neutron stars are objects formed from the collapsed cores of large stars following a supernova explosion. They are also known as pulsars due to the pulses of radiation they emit as they rotate at high speeds.

These stars are generally examined using radio wave and X-rays, and researchers say the addition of the infrared spectrum to their studies opens up a wide range of new possibilities.

This specific object, known as RX J0806.4-4123, belongs to a group of pulsars known as “the magnificent seven” that scientists say are far hotter than they ought to be considering their age.

As for the source of its bright glow, the researchers think there must be something else interacting with the neutron star to create this effect.

“One theory is that there could be what is known as a ‘fallback disc’ of material that coalesced around the neutron star after the supernova,” said Professor Bettina Posselt, an astrophysicist at Pennsylvania State and the leader of the team that identified the distant glow.

“Such a disc would be composed of matter from the progenitor massive star. Its subsequent interaction with the neutron star could have heated the pulsar and slowed its rotation.

“If confirmed as a supernova fallback disc, this result could change our general understanding of neutron star evolution.”

The second possible explanation for the infrared emission from this neutron star is that it could be a “pulsar wind nebula.”

In this scenario, an energetic wind coming from the star could be interacting with gas in space to create the infrared effect.

“As the neutron star travels through the interstellar medium faster than the speed of sound, a shock can form where the interstellar medium and the pulsar wind interact,” said Professor Posselt.

“The shocked particles would then emit synchrotron radiation, causing the extended infrared signal that we see.

“Typically, pulsar wind nebulae are seen in X-rays and an infrared-only pulsar wind nebula would be very unusual and exciting.”

Describing the star as “unusual”, Nasa said their new James Webb Space Telescope – which is currently under development as a replacement for Hubble – will help them pinpoint exactly what is going on around this neutron star.

The discovery was documented in the Astrophysical Journal.