Neutron Star Merger Simulation with Gamma-ray Observations

This animation follows the gravitational wave and density changes in a simulated neutron star merger and compares them to measurements of a short gamma-ray burst observed by NASA’s Compton mission on July 11, 1991. Dark purple colors represent the lowest-density material, while yellow-white shows the highest. An audible tone and a visual frequency scale (at left) track the steady rise in the frequency of gravitational waves as the neutron stars close. When the objects merge at 19 seconds, the gravitational waves suddenly jump to frequencies of thousands of hertz and bounce between two primary tones. A magenta line appears at left to illustrate how quasiperiodic oscillations (QPOs) found in the gamma-ray emission correlate to those of the simulated gravitational waves. At the same time, a graph at upper right traces the changes in gamma-ray brightness observed during the same burst. To symbolize the ultimate formation of a black hole, a dot has been added at the center. Credit: NASA’s Goddard Sp