We can gain unique insights about our Universe through observations with the multiple messengers of gravitational waves and electromagnetic waves at radio to gamma-ray frequencies observed with telescopes on Earth and in space.

Gravitational waves are ripples in space-time predicted by Einstein's theory of general relativity. They are produced by accelerating masses and can be used to study objects like black hole binaries which do not emit visible light. Our experiment is sensitive to low-frequency gravitational waves with periods of years to decades.

Galaxies have evolved through cosmic time through consecutive mergers with other galaxies. We will gain unique insights into this important process by detecting the gravitational waves produced by extremely massive pairs of black holes at the cores of merged galaxies.

Neutron stars are the collapsed cores of massive stars which have ended their lives in cataclysmic supernova explosions. Pulsars are rapidly rotating, highly magnetic neutron stars which emit beamed radio emission, like cosmic lighthouses. They are unique laboratories for a variety of fundamental physics experiments.