Teasing apart Earth's magnetic signals
The European Space Agency has produced a spectacular new view of ocean tides as they sweep around the Earth. It is not a rendering of the bulging movement of water directly, but rather its magnetic signature. As the Moon pulls the salty seas through our planet's global magnetic field, electric currents are generated. And these currents then induce their own magnetic signals, which have now been mapped in exquisite detail by a trio of Esa satellites known as Swarm. Prof Nils Olsen, from the Technical University of Denmark, spoke with our science correspondent Jonathan Amos.
10 Apr 2018