From American Scientist:
However silent the twinkling stars seem in the clear night sky, Einstein’s theory of spacetime tells us that the real universe is a noisy place, alive with vibrating energy. Space and time, says Craig Hogan, carry a cacophony of vibrations with textures and timbres as rich and varied as the din of sounds in a tropical rain forest or the finale of a Wagnerian opera. A space-based antenna now being designed will complement terrestrial laser interferometers to allow astronomers to listen to these rumblings—gravitational waves that depict the death dances of neutron stars or the collisions of massive black holes in distant galaxies. Hogan says the waves will map distant reaches of the universe, tell us much about spacetime itself—and possibly detect whispering evidence of cosmic strings.
So how would you feel if suddenly, as you quietly admired a dark and starry sky, you heard the stars making all kinds of crazy noises? After the initial shock of being jolted out of your poetic reverie, I think you would find that the universe felt much more immediate, present, real and alive. It is one thing to see flashes of lightning in the distance, quite another to be shaken by the sound of rolling thunder. Hearing the universe is more like touching than looking. Happily, astronomers are finding ways to do that—to feel as well as see the active universe around us.