Scientists have completed an analysis of audio recorded on Mars by NASA's Perseverance rover. The sounds, which include a rock laser, Ingenuity helicopter, and the Martian wind, were captured by the rover's SuperCam microphone and another microphone located on its chassis. The new study revealed the speed of sound is slower on Mars than on Earth. On the Red Planet, high-pitched sounds travel at 559 mph while lower-pitched sounds move at 537 mph (on Earth sound travels at 767 mph). One of the biggest takeaways was how silent it is on Mars. "At some point, we thought the microphone was broken, it was so quiet," said astrophysicist Sylvestre Maurice.