When galaxies with supermassive black holes at their centres collide, they could produce a burst of gravitational waves within just 10 million years.

Gravitational waves were first detected earlier this year, sparking great interest in finding more. Some scientists have predicted that wave production happens on timescales of a billion years or more, which would mean future searches would detect relatively few waves. Fazeel Mahmood Khan at the Institute of Space Technology in Islamabad and his colleagues simulated a galaxy collision and predicted that there are many more such waves to detect.

This is a promising finding for projects that aim to look for gravitational waves, such as one proposed by the European Space Agency using the Evolved Laser Interferometer Space Antenna.

Astrophys. J. 828, 73 (2016)