Tim Peake uses an alarm clock to help explain how sound travels. The International Space Station is the home to astronauts during their stay in space. This structure allows them to breathe oxygen as it removes waste gases and maintains a constant temperature. Tim explains that inside the space station it is a very noisy environment, but he describes how in space during a spacewalk there is complete silence. Fran Scott demonstrates using Tim Peake’s alarm clock that for sound to travel it requires a medium of air. She removes the air from a bell jar using a pump to show how we are unable to hear the alarm clock in a vacuum. Resulting in a conclusion that sound travels by air particles vibrating.

Could be used to engage pupils with the current mission to the International Space Station focusing on British astronaut Tim Peake. This can complement an introduction to sound, waves and space.