Hear the spooky sounds of Earth’s magnetic field – captured by Swarm Satellite Mission

The Earth is surrounded by a system of magnetic fields, called the magnetosphere, which is essential for life on Earth. However, the magnetic field is not something that we can actually see by itself, or ever hear. But, remarkably, scientists at the Technical University of Denmark have taken magnetic signals measured by ESA’s Swarm satellite mission and converted them into sound. For something that protects us, the result is quite frightening.

Earth’s magnetic field is a complex and dynamic bubble that protects us from harmful cosmic radiation and charged particles carried by powerful solar winds from the Sun. When these particles collide with atoms and molecules – mostly oxygen and nitrogen – in the upper atmosphere, some of the energy from the collisions is transformed into green-blue light typical of the aurora borealis. These “Aurora Borealis” can sometimes be seen from high northern latitudes.

While the Aurora Borealis provides a visual display of charged particles from the Sun interacting with the Earth’s magnetic field, it’s an entirely different matter to actually be able to hear the Earth’s generated magnetic field or its interaction with the solar winds.

Our magnetic field is largely generated by a superheated, swirling ocean of liquid iron that makes up the outer core about 3,000 km (1,900 miles) below our feet. Acting like a rotating conductor in a bicycle dynamo, it creates electric currents which, in turn, generate our ever-changing electromagnetic field.

ESA’s trio of Swarm satellites, which launched in 2013, are being used to understand exactly how our magnetic field is generated by precisely measuring magnetic signals that come not only from the Earth’s core, but also from the mantle, crust and oceans, as well as the ionosphere and magnetosphere. Swarm also opens new perspectives on weather in space.

Klaus Nielsen, musician and project supporter from the Technical University of Denmark, explains: “The team used data from ESA’s Swarm satellites, as well as other sources, and used these magnetic signals to manipulate and control a sound representation of the central field. The project has certainly been a rewarding exercise in bringing art and science together.

It may sound like nightmares, but, remarkably, this audio clip depicts the magnetic field generated by the Earth’s core and its interaction with a solar storm.

“We had access to a very interesting sound system consisting of more than 30 speakers dug into the ground in Solbjerg Square in Copenhagen.

“We set it up so that each speaker represents a different place on Earth and shows how our magnetic field has fluctuated over the past 100,000 years.

“Throughout this week, visitors will be able to hear the incredible rumble of our magnetic field – so if you’re in Copenhagen, come check out this unique opportunity.

“The rumble of the Earth’s magnetic field is accompanied by a depiction of a geomagnetic storm resulting from a solar flare on November 3, 2011, and indeed it sounds quite frightening.”

The intention, of course, is not to scare people – it’s a quirky way of reminding us that the magnetic field exists and that although its rumble is a little unnerving, the existence of life on Earth depends on it.

Loudspeakers in Solbjerg Square in Copenhagen, Denmark, will broadcast the rumble of the Earth’s magnetic field between October 24 and 30 at around 8 a.m., 1 p.m. and 7 p.m.