Illustrations of Neutron Merger and Black Hole
A new study using Chandra data of GW170817 indicates that the event that produced gravitational waves likely created the lowest mass black hole known. The first artist's illustration (left) shows a key part of the process that created this new black hole, as the two neutron stars spin around each other while merging. (The purple material depicts debris from the merger.) The second artist's illustration (right) shows the black hole that resulted from the merger, along with a disk of infalling matter and a jet of high-energy particles.
(Credit: NASA/CXC/M.Weiss)

Full-Field X-ray Images of GW170817 / NGC 4993
The Chandra data of GW170817 (top most source) show levels of X-rays that are a factor of a few to several hundred times lower than expected for a rapidly spinning, merged neutron star and the associated bubble of high-energy particles, implying a black hole likely formed instead.
(Credit: NASA/CXC/Trinity University/D. Pooley et al.)