In 1916, Albert Einstein had a theory. He thought that somewhere out in the universe, there were collisions in space. These collisions could cause little sound waves in the fabric of space-time that might carry many secrets of the distant universe. But it was only a theory. He could not prove it in his lifetime. Many years later, an immigrant scientist named Gabriela Gonzalez asked the same questions. Armed with modern technology, she joined a team of physicists who set out to prove Einstein's theory. At first, there was nothing. But then. . . they heard a sound. Gabriela and her team examined, and measured, and re-measured until they were sure. Completing the work that Albert Einstein had begun 100 years earlier, Gonzalez broke ground for new space-time research. In a fascinating picture book that covers 100 years, 2 pioneering scientists, and 1 trailblazing discovery, Patricia Valdez sheds light on a little known but extraordinary story.