How much power did the collision emit relative to the visible universe?

How much power did the collision emit relative to the visible universe?

• A. 50x the entire visible universe
• B. 5x the entire visible universe
• C. 100x the entire visible universe
• D. 0.5x the entire visible universe

Answer: (A)

Power is energy per unit time, so the question is about how large the instantaneous energy output was during the peak of the collision. In the landmark black-hole merger, a huge amount of energy was dumped into gravitational waves in a tiny fraction of a second. The peak luminosity (the power at the brightest moment) is estimated to be around 10^49 watts. Estimates for the total light power of all stars visible in the night sky over time are much lower, on the order of 10^47–10^48 watts. Comparing those, the collision’s peak power comes out roughly fifty times greater than the combined power of all visible stars. So the best match among the choices is about 50x the entire visible universe. This emphasizes how briefly huge power outputs can occur in gravitational-wave events even if the total energy isn’t enormous on human timescales.

Power is energy per unit time, so the question is about how large the instantaneous energy output was during the peak of the collision. In the landmark black-hole merger, a huge amount of energy was dumped into gravitational waves in a tiny fraction of a second. The peak luminosity (the power at the brightest moment) is estimated to be around 10^49 watts. Estimates for the total light power of all stars visible in the night sky over time are much lower, on the order of 10^47–10^48 watts. Comparing those, the collision’s peak power comes out roughly fifty times greater than the combined power of all visible stars. So the best match among the choices is about 50x the entire visible universe. This emphasizes how briefly huge power outputs can occur in gravitational-wave events even if the total energy isn’t enormous on human timescales.