Researchers are puzzled: mysterious signal at black hole – Science

Gravitational wave detectors find a surprising double system. A black hole has merged with a second object. Astronomers from the Max Planck Institute consider the second object puzzling. The unequal pair questions the current understanding of how these systems came into being and developed. Its mass is between the heaviest known neutron star and the lightest black hole in a mass gap.

opposites attract

“The signal GW190814 is an unexpected and really exciting discovery,” says Abhirup Ghosh from the Max Planck Institute for Gravitational Physics in Potsdam. It is the first time that such different objects merge and emit gravitational waves. “If it is actually a black one Hole is the lightest known, but if it is a neutron star, it is the most massive one that we have ever seen in a double system, ”said Ghosh.

A musical romance

Together they make “music”. “Because the masses of the objects are so different, we were able to clearly identify the hum of a higher harmonic of the gravitational wave, which resembles the overtones of musical instruments,” says Jonathan Gair, group leader at the Max Planck Institute in Potsdam.