Scientists have reportedly found evidence that proves that there’s a second magnetic field generated by the Earth. Data from the European Space Agency’s (ESA) Swarm satellites has revealed that our planet has an additional magnetic field produced by the ocean’s tides.
The magnetic field has been detected by a trio of satellites called the Swarm that was launched into orbit back in 2013 to study and monitor Earth’s magnetic behavior. The satellites orbit at 300-530km (186-330 miles) around Earth.
Nils Olsen, the head of the geomagnetism at the Technical University of Denmark, said that the recently discovered magnetic field is pretty tiny in size. It’s about 2-2.5 nanotesla at satellite altitude. It was difficult to detect because it is about 20,000 times weaker than the Earth’s global magnetic field.
Notably, the main magnetic field of our planet is the result of the movement and swirling of superheated liquid iron in the outer core. Factors such as the flow of the ocean and magnetized rocks in the crust also have an effect on the overall magnetic signal of the planet. According to the scientists, the newly-tracked magnetic field is created as the Moon pulls the Earth’s oceans through the magnetic field.
They used data obtained from the Swarm satellites to determine the magnetic signals of tides from the ocean surface to the seabed. The study also presented a clear picture of how the ocean flows at all depths which can help scientists understand more about climate change.
The researchers involved in this study made a new map of Earth’s magnetic field using Swarm measurements, data from a German spacecraft called Champ, and information collected by airplanes and ships. They also created an animation of changes in tidal signal over a 24 hour period, which was presented at the European Geosciences Union General Assembly (EGU) in Vienna, Austria.