One of the most studied objects in the sky is a supernova that first became visible with the naked eye in our sky on February 24, 1987. It was the first supernova visible with the naked eye in 400 years and was dubbed Supernova 1987A. Since its discovery, researchers have been looking for the squashed stellar core that would’ve been left behind when the star exploded, known as a neutron star.
A group of astronomers using data from NASA space missions and ground-based telescopes have finally found the neutron star hiding inside the supernova. Supernova 1987A is located in the Large Magellanic Cloud, a smaller companion galaxy to the Milky Way about 170,000 light-years from Earth. Researchers on the project used NASA data from the Chandra X-Ray Observatory and previously unpublished data from the NASA Nuclear Spectroscopic Telescope Array combined with data from ground-based observations made using the Atacama Large Millimeter Array.
For the last 34 years, astronomers have sifted through the debris left behind in the supernova explosion, searching for the neutron star expected to be there. When a star explodes into a supernova, it collapses onto itself before blasting its outer layers into space. The compression of the stellar core turns it into an extraordinarily dense object with the mass of the sun squeezed into an object about 10 miles across.
These remnants are called neutron stars because they are nearly exclusively made of densely packed neutrons. Neutron stars that rotate rapidly and are highly magnetized are called pulsars and produce a beam of radiation astronomers can detect as pulses as it sweeps across the sky. Scientists note that a subset of pulsars produced winds from their surfaces that are sometimes propelled to nearly the speed of light, creating intricate structures of charged particles and magnetic fields called “pulsar wind nebulae.”
With the new observational data, the 000 discovered low-energy x-rays emanating from the nebula along with evidence of high-energy particles. Astronomers believe there are two likely explanations for the energetic x-ray emission, including either a pulsar wind nebula or particles being accelerated to high energies by the blast wave of the explosion. The data in the latest x-ray study supports the case for a pulsar wind nebula.