Yes, sound waves can travel at different speeds on different planets. The speed of sound depends on the properties of the medium through which it propagates, such as the density, temperature, and composition of the material. Since different planets have different atmospheric compositions and conditions, the speed of sound can vary.
For example, on Earth, at sea level and at a temperature of about 20 degrees Celsius (68 degrees Fahrenheit), the speed of sound is approximately 343 meters per second (1,125 feet per second) in dry air. However, on a planet with a different atmospheric composition or different temperature, the speed of sound will be different.
As an example, let's compare the speed of sound on Earth to that on Mars. Mars has a much thinner atmosphere compared to Earth, primarily composed of carbon dioxide. Due to the lower atmospheric density, sound waves on Mars propagate more slowly than on Earth. The average speed of sound on Mars is around 240 meters per second (787 feet per second), which is notably slower than on Earth.
It's important to note that the speed of sound can also vary within a planet's atmosphere. Factors like temperature, altitude, and atmospheric composition can influence the speed of sound, creating variations at different locations within the same planet.