Physicists are searching for gravitational waves all across the spectrum.
Gravitational waves, or ripples in the fabric of space-time, have captured the imagination of physicists since Albert Einstein first predicted them in 1916. But it wasn’t until the 1960s that Joseph Weber, an experimental physicist at the University of Maryland, built the first machine meant to find them.
About 50 years later, scientists finally did it; the Laser Interferometer Gravitational-Wave Observatory detected gravitational waves coming from the merger of two black holes.
The merging black holes LIGO discovered emit gravitational waves at relatively high frequencies. But more massive objects, such as supermassive black holes and merging galaxies, produce waves with longer periods and lower frequencies.
Astronomers are using a wide variety of instruments to seek out gravitational waves at these different frequencies to detect the cosmic events that produce them.