They found a neutron star left behind by the 1987 supernova.

On February 23, 1987, astrophysicists around the world received a unique gift from space: a supernova shone in the night sky, the first in 400 years since the one noticed by Johannes Kepler in 1604. This stellar explosion located in the Large Magellanic Cloud was named SN 1987A and became the most studied supernova in history. But due to the presence of dense clouds of stardust, the neutron star whose remnant astrophysicists had expected to find was not detected, and the possibility that it had collapsed to form a black hole could not be ruled out.

Now, a team of astronomers led by Claes Fransson from Stockholm University (Sweden), using the instruments of the James Webb Space Telescope, has found the first convincing evidence of the existence of this neutron star in the remnant of supernova 1987A. JVST).

The results, which will be published this Thursday in the journal The scienceare based on the observation of a series of infrared emissions detected by JWST and which, using spectroscopy, allow the composition and movement of gas to be studied.

In particular, the authors discovered emission lines of highly ionized argon and sulfur gas located near the site of the star’s explosion, which can only be explained by the presence of a bright source of ultraviolet and X-ray radiation from the neutron star, either directly or indirectly. If it were a black hole, the study authors explain, it would not produce the types of lines observed in the spectrum.

The end of the mystery

“We now know that there is a compact source of ionizing radiation, likely coming from a neutron star,” Fransson said in a press release. “We’ve been looking for this since the explosion, but we had to wait until JWST could verify the predictions.” “The mystery of whether there is a neutron star hiding in the dust has been going on for more than 30 years, and it’s amazing that we have solved it,” adds Mike Barlow, an astrophysicist and co-author of the paper.

The mystery of whether there is a neutron star hiding in the dust has lasted more than 30 years, and it’s amazing that we have solved it.

According to Spanish astrophysicist Miguel Santander, who was not involved in the study, this result “caps almost four decades of intense search for the neutron star we expected to find at the center of a supernova remnant (something for which there were already clues, but no observations). ) Direct) and once again shows the enormous potential of JWST for studying the Universe.”

Various previous studies, recalls Jonay Gonzalez, a researcher at the Institute of Astrophysics of the Canary Islands (IAC), allowed us to conclude that the supernova remnant is a neutron star. “But in this new paper, the James Webb Telescope provides unprecedented improvements in imaging with much higher resolution, both special and spectral,” he says. “This study represents another step toward confirming the origin of this supernova.”

Supernovae are the spectacular end result of the collapse of stars with a mass 8 to 10 times the mass of the Sun. They are the main sources of chemical elements (such as carbon, oxygen, silicon and iron) that make life possible. The collapse of the cores of these exploding stars can lead to the formation of much smaller neutron stars, composed of the densest matter in the known Universe, or black holes. There is no other object similar to the neutron star of Supernova 1987A, so close to us and formed so recently. As the material around it expands, we’ll see more of it over time, the researchers say.