On February 11, a team of scientists announced that they heard the sound of two black holes colliding. This sound was the first proof that gravitational waves exist, something that Albert Einstein predicted 100 years ago. Einstein thought that cataclysmic events (such as supernovas) created ripples through space and time. He called these ripples gravitational waves. Because these waves had to travel very long distances to reach earth, Einstein thought they would be too small to detect. But last fall, scientists used mirrors and lasers to record these tiny changes and translate them to a chirp. This discovery opens a whole new way of studying the universe. Scientists believe it will help us study things that happened much farther away and longer ago than ever before.
Read more about gravitational waves and listen to the chirp.
