An artist’s impression of the end result of a merger between a 23-solar-mass black hole and a much less massive companion, possibly the lightest known black hole or a new class of heavyweight neutron star. Image: Alex Andrix
On 14 August 2019, gravity waves rippled through the solar system that were generated during the merger of a 23 solar mass black hole and a much lighter 2.6 solar mass companion. Researchers with the Advanced LIGO and Advance Virgo gravity wave observatories said the lighter companion is either the least-massive black hole ever detected or the heaviest neutron star.
Before the detection, the heaviest neutron star known was one with no more than 2.5 times the mass of the Sun and the lightest black hole weighed in at about five solar masses. A major question mark has been what, if anything, inhabits the mass gap between neutron stars and black holes?
“We’ve been waiting decades to solve this mystery” said Vicky Kalogera, a professor at Northwestern University. “We don’t know if this object is the heaviest known neutron star, or the lightest known black hole, but either way it breaks a record.”
Added co-author Patrick Brady, a professor at the University ...