Astronomers have detected the most massive example of a neutron star, classified as a “black widow”, which has grown especially heavy by swallowing most of the mass of a companion star.
The researchers said the star, rotating 707 times per second, has a mass about 2.35 times that of our sun. It is perhaps the greatest possible mass for this type of object before it collapses and forms a black hole.
A neutron star is the collapsed compact core of a massive star that exploded as a supernova at the end of its life cycle.
The one described by the researchers is a highly magnetized type of star called a pulsar, which shoots beams of electromagnetic radiation from its poles. As they spin, these beams appear to pulsate from an Earth observer’s perspective – similar to the rotating light of a lighthouse.
Only one other neutron star rotates faster than this one as far as is known.
“The heavier the star, the denser the material in its core,” said Roger Romani, director of the Center for Space Science and Astrophysics at Stanford University and co-author of the research published this week in Astrophysical Journal Letters.
“So, as the heaviest known neutron star, this object features the densest material in the observable universe. If it were any heavier, it would collapse and become a black hole, and whatever was inside would be forever isolated from observation. ,” added Romani.