Up to several times a day, the Sun blasts bursts of energetic electrons into space, which emit radio waves as they collide with other charged particles. These bursts are picked up by the Radio and Plasma Waves (RPW) instrument on the ESA-led Solar Orbiter spacecraft.
A team at Radboud University/Paris Observatory has now divided five years of RPW data into 15 000 six-hour chunks. This video shows one such chunk of data. As the blasted electrons move further into space, away from the Sun, there are fewer charged particles to interact with, and the radio frequency drops. Each ‘hockey stick’ shape is a real radio burst in action.
In this sonification, the radio waves are converted into sound, with lower frequency radio waves corresponding to lower frequency sound waves. Whenever a radio burst occurs, we hear a ‘pyoong’ sound that gets lower in tone before fading out completely. The timeline has been sped up; the biggest radio burst in the middle of the graph lasted about three hours in real life!