Evidence of a neutron star hidden deep inside Supernova 1987A is helping astronomers solve a 33-year-old mystery surrounding one of the brightest star explosions ever observed. On Feb. 23, 1987, astronomers witnessed an incredibly bright stellar explosion, also known as a supernova. Using the Atacama Large Millimetre/submillimetre Array (ALMA), researchers believe they have found that explosion’s remnants, a super dense corpse called a neutron star, hiding within the dust of the supernova. High-resolution ALMA images revealed what researchers described as a hot “blob” that is brighter than its surroundings and located at the supernova’s dusty core. If confirmed, this neutron star would be the youngest known to date, according to a statement. “We were very surprised to see this warm blob made by a thick cloud of dust in the supernova remnant,” Mikako Matsuura, an astronomer at Cardiff University and one of the researchers who spotted the blob, said in the statement. “There has to be something in the cloud that has heated up the dust and which makes it shine. That’s why we suggested that there is a neutron star hiding inside the dust cloud.”
Their findings were published in November 2019, in The Astrophysical Journal. At the time, however, the researchers could not definitively say what the glowing blob was, as it was believed to be too bright to be a neutron star. A new paper offers an explanation for that brightness in a neutron star: the glowing blob is consistent with thermal emission from a very young neutron star that is still really hot from the supernova explosion, according to the statement. The researchers estimate the temperature of the 15.5 mile (25 kilometre) wide neutron star is approximately 9 million degrees Fahrenheit (5 million degrees Celsius), which provides enough energy to explain the blob’s brightness. The study also suggests the neutron star is located off-centre, as researchers expect, due to the powerful stellar blast.