Was the blue outburst the creation of a superdense star?
Astronomers may have caught the moment when a supernova became a neutron star, perhaps even a black hole.
In June 2018, telescopes around the world homed in on a flash of blue light 100 times brighter than a supernova, called AT2018cow (or ‘The Cow’ for short), coming from a galaxy 200 million lightyears away. Follow-up observations found the object flashed out X-rays every 4.4 milliseconds, which suggests an object 1,000kmwide and makes a neutron star or black hole the most likely cause. It’s thought one of these formed in a collapsing star, then devoured the material around it to generate an energy burst.
“We have likely discovered the birth of a compact object in a supernova,” says lead author Dheeraj Pasham, from the Massachusetts Institute of Technology. “This happens in normal supernovae, but we haven’t seen it before because it’s such a messy process. We think this new evidence opens possibilities for finding baby black holes or baby neutron stars.” www.mit.edu