Australian led team of astronomers has reportedly used radio telescopes in Australia and Chile to see inside the remains of a supernova. The team of researchers has published the results of the extensive ‘autopsy’ on Supernova 1987A using the Atacama Large Millimeter/submillimeter Array (ALMA) telescope in Chile’s Atacama Desert and the Australia Telescope Compact Array (ATCA) in Australia.
The supernova was first observed in the southern hemisphere in 1987, when a large star exploded at the edge of a nearby galaxy called the Large Magellanic Cloud. Since then, the remnant of Supernova 1987A has been examined by researchers worldwide.
“We’ve been able to distinguish radiation being emitted by the supernova’s expanding shock wave from the radiation caused by dust forming in the inner regions of the remnant,” PhD candidate Giovanna Zanardo, of the University of Western Australia, who led the team, said. “It means we’re able to separate the different types of emission we’re seeing and look for signs of a new object which may have formed when the star’s core collapsed,” he added.
But the amazing thing is that these observations showed signs of something never seen before at the centre of the remnant. It’s amazing that only now, with large telescopes like ALMA and the upgraded ATCA, we can peek through the bulk of debris ejected when the star exploded and see what’s hiding underneath,” Ms Zanardo said.
The new research, reported in the Astrophysical Journal, has detected signs of what could be a pulsar wind nebula driven by a spinning neutron star or pulsar: “We’ve never seen a neutron star so young,” says Ms. Zanardo. “If this is a pulsar, then a quarter-century-old mystery about what supernova 1987A created, will have been solved. (…) The beauty about the star that exploded to create supernova 1987A is that it was a blue supergiant about 20 times the mass of our Sun, so it could have produced either a neutron star or a black hole.”
More research published not long ago in the Astrophysical Journal as well, also attempts to shine a light on another long-standing mystery surrounding the supernova remnant. Since 1992 the radio emission from one side of the remnant has appeared ‘brighter’ than the other. In an effort to solve this puzzle, Dr Toby Potter, another researcher from ICRAR’s UWA node has developed a detailed three-dimensional simulation of the expanding supernova shockwave. The time evolving model shows that the eastern (left) side of the expanding shock front expands more quickly than the other side, and generates more radio emission than its weaker counterpart.