Recently I’ve been collecting space-themed songs (for a McTyeire Hall event called the Galaxy Gala!), and then I thought of something I’ve heard of before: sounds coming from space!
Because space is a vacuum, sound waves cannot travel through it. However, many objects within the Solar System do emit radio waves, and NASA scientists have converted some of these to sound for our listening pleasure! For instance, you can hear the drone of Jupiter’s magnetosphere (courtesy of NASA JPL), including the sharp drop in frequency right as the spacecraft Juno enters the magnetosphere (this is called a bow shock, equivalent to a sonic boom here on Earth). You can hear plenty more at NASA’s “Spooky Sounds” Playlist!
But rewind to where I said sound waves cannot travel through space. This isn’t always entirely true – interstellar space is not completely empty, as it contains clouds of gas and dust. These can transmit sound waves, albeit at frequencies far too low for us humans to actually hear. (For reference, the lowest frequency we can hear is 20 Hz, which means one oscillation per 1/20 of a second.) For example, there is a supermassive black hole in the Perseus Cluster, some 250 million light-years away, that produces a constant drone 57 octaves below middle-C (technically it is a B-flat). The cycle of this sound is one oscillation per 10 million years, which means the length of its cycle is far longer than humans have even been around!
Have you heard any other interesting sounds from space? Or do you know of any cool songs about space?