Astronomers have named the most likely type of unknown object hiding inside the remnants of supernova SN 1987A, whose light reached Earth on February 24, 1987. The outbreak occurred in the Large Magellanic Cloud at a distance of 170 thousand light-years from Earth and became the first supernova visible to the naked eye in 400 years. According to the researchers’ article accepted for publication in The Astrophysical Journal and available in the arXiv preprint repository, a pulsar is hidden inside the remains of a deceased star.
Observations from the Chandra X-ray Observatory, NuSTAR Space Observatory, and ALMA Atacama Large Array have confirmed that there is indeed a neutron star at the center of the nebula generated by SN 1987A. The proof was the registration of low-energy X-rays, which interact with the surrounding matter, as well as higher-energy particles.
In fact, high-energy radiation can indicate two possible sources: the acceleration of particles by a supernova blast wave, or plerion, a nebula that is powered by the wind from a pulsar. However, observations refute the version of a blast wave, confirming the existence of a pulsar. The brightness of the X-rays remained the same throughout 2012-2014, while the brightness of the radio emission increased, which cannot be explained by the blast model. In addition, in the rejected scenario, the acceleration of electrons to energies observed by NuSTAR should occur over 400 years, which is more than ten times the age of the observed supernova remnant.
If future research proves the presence of a pulsar, it will become the youngest object of this type known. The material surrounding the pulsar strongly absorbs X-rays, making it undetectable. In about 10 years, the nebula is expected to dissipate slightly, and the radiation from the neutron star will become more visible.