These Eerie Sounds Of Earth's Magnetic Field Feel Like Something Out Of A Horror Movie
One of the reasons that Earth is able to support life is an important property of the planet we can't usually see: its magnetic field. This field protects the planet from harmful space radiation as particles from the sun get caught in regions around the planet called the Van Allen belts. Sometimes, parts of this magnetic field are visible, such as in aurorae like the Northern Lights, which are seen around the poles and are created when charged particles from the sun interact with the magnetic field. But most of the time, the magnetic field keeping us safe is invisible to us.
Relatively recently, however, researchers working with the European Space Agency (ESA) have come up with a way for us to experience the magnetic field. But it's not through vision — it's through sound. A team from the Technical University of Denmark has turned signals from the planet's magnetic field into sound, and the result sounds like something out of a horror movie.
The sounds — which are available on SoundCloud — are scratchy, rubbing, and kind of disturbing. They were created using data from ESA's Swarm satellite mission, a trio of satellites launched in 2013 that observes the Earth's magnetic field to understand research topics like the Earth's core and space weather. Two of the satellites orbit side by side at around 280 miles above the surface, while the third is at a higher altitude of 330 miles, and all three are in polar orbits which allow them to observe all the way around the Earth.
Turning magnetic field readings into sounds
The planet's magnetic field isn't a simple shape, as it is pulled into a tail form due to particles coming from the sun. The field is created by the liquid metal within the planet's core, and as this liquid moves and swirls it creates electrical currents which create the magnetic field. Researchers are still trying to understand many aspects of the magnetic field such as how it is affected by solar activity, how and why the magnetic poles of the planet flip periodically, and how it compares to similar magnetic fields on other planets.
To help people understand more about the importance of the planet's magnetic field and how it is being studied, a team including musicians and scientists worked together to create the soundscape. "The team used data from ESA's Swarm satellites, as well as other sources, and used these magnetic signals to manipulate and control a sonic representation of the core field," explained team member musician Klaus Nielsen of the Technical University of Denmark to the ESA. "The project has certainly been a rewarding exercise in bringing art and science together."
The team also arranged a sound installation in Copenhagen, with 30 loudspeakers put into the ground in the Solbjerg Square to project the soundscape. Different speakers represented different locations across Earth, so visitors could hear how the magnetic field varies through time and location. "The rumbling of Earth's magnetic field is accompanied by a representation of a geomagnetic storm that resulted from a solar flare on 3 November 2011, and indeed it sounds pretty scary," said Nielsen.