PARIS - Europe next week will launch a trio of hi-tech satellites to explore someth ing that may seem utterly mundane: Earth's magnetic field. After all, magnetism has been with us for billions of years.
We harness it in innumerable ways, in navigation and electrical devices. What's new?
Well, plenty, actually.
If all goes well, the 230 million euro (S$344.23 million) Swarm mission will explain some of the weird things happening to the planet's magnetism.
And they are more than just curiosities.
"Earth's magnetic field is a very important thing. It makes life possible on Earth by providing shelter against radiation from space," said Albert Zaglauer, project manager at Astrium, which made the three satellites.
The field is fickle, he said.
"The magnetic pole is changing, and the magnetic field is changing too. Why?"
Earth's magnetism derives from superheated liquid iron and nickel, which swirl in the outer core about 3,000 kilometres (1,800 miles) beneath the surface.
Like a spinning dynamo, this subterranean metal ocean generates electrical currents and thus a magnetic field.
But contrary to what many may think, the field is not constant and immutable.