Heaviest neutron star to date is a ‘black widow’ eating its mate

July 26, 2022

A dense, collapsed star spinning 707 times per second — making it one of the fastest spinning neutron stars in the Milky Way galaxy — has shredded and consumed nearly the entire mass of its stellar companion and, in the process, grown into the heaviest neutron star observed to date.

Weighing this record-setting neutron star, which tops the charts at 2.35 times the mass of the sun, helps astronomers understand the weird quantum state of matter inside these dense objects, which — if they get much heavier than that — collapse entirely and disappear as a black hole.

“We know roughly how matter behaves at nuclear densities, like in the nucleus of a uranium atom,” said Alex Filippenko, Distinguished Professor of Astronomy at the University of California, Berkeley. “A neutron star is like one giant nucleus, but when you have one-and-a-half solar masses of this stuff, which is about 500,000 Earth masses of nuclei all clinging together, it’s not at all clear how they will behave.”

Berkeley News