Using data from the ESA Swarm satellite, scientists have discovered an entirely new type of magnetic wave traveling through the outermost part of the Earth’s outer core. This discovery, which opens a new window on a hitherto unknown world, was presented at the ESA Living Planet Symposium. The corresponding article was published in the Proceedings of the National Academy of Sciences.
The geomagnetic field can be compared to a giant bubble protecting the planet from charged particles coming from the Sun and from the surrounding Galaxy. Without a magnetic field, life familiar to humans would be impossible. Therefore, knowing how and where this magnetic field is generated, how it interacts with the solar wind, why it experiences noticeable fluctuations and at times seriously weakens, is a vital necessity.
Solar storms can damage communications networks, sometimes seriously damaging navigation systems and satellites. Much of the geomagnetic field is generated by an ocean of superheated, swirling liquid iron that makes up the Earth’s outer core at a depth of 3,000 km. Acting like a rotating conductor in a dynamo, this ocean generates electrical currents and a constantly changing electromagnetic field.
The ESA Swarm mission, consisting of three Alpha, Bravo and Charlie satellites, began operations in 2014, allows you to track changes in the geomagnetic field, as well as capture other electromagnetic signals emanating from the earth’s core, crust, oceans, ionosphere and magnetosphere.
Prior to this, the core was explored by the Canadian satellite CASSIOPE, which, in turn, became the successor to a similar CHAMP project, which had been hanging in orbit since 2000.
Discovered by this mission, new mysterious electromagnetic waves passing along the surface of the outer core of the Earth, where this core passes into the mantle, propagate every seven years.
We do not know what these waves are and where they come from, but thinking within the generally accepted theory of the planetary magnetic field, some large formation appeared in the outer core, which moves at a speed of 1500 kilometers per year, 4 kilometers per day or 170 meters per hour. This formation drives the magnetic wave.
“Geophysicists have long predicted the existence of such waves, but it was believed that they operate on much longer time scales than our studies have shown,” says lead author Nicolas Gillet from the French University of Grenoble-Alpes.
“Studies of the geomagnetic field with sensors placed on the earth’s surface showed that there was some kind of wave action, but we needed the global coverage that only measurements from space could provide to show what was really happening there. We combined the Swarm satellite data, as well as data from the earlier German Champ mission and the Danish Ørsted mission, with a computer model of the geodynamo, and this led us to our discovery.”
Due to the rotation of the Earth, these waves line up along its movement, and the fluctuations of the geodynamo and magnetic fields, associated with these waves are most strongly felt near the equatorial region of the earth’s core.
The temperature of the outer core is 4000 – 6000 degrees Celsius, so there are no submarines in this underground river. And since there are no submarines, then such an object that drives a stable magnetic wave can only be a vortex formation in liquid metal, which moves there as if in the atmosphere.
Previously, this formation was obviously non existent, otherwise it would have been seen, but now it seems that there is some kind of new dynamic vortex in the core.
It is possible that numerous atmospheric wonders of recent times, such as sprites and jets, are associated with its appearance. It is also most likely that this vortex formation is somehow connected with the pole shift, which, apparently, will be in the very foreseeable future.