The Greenwich Compasses are about to record something new in over 300 years – 09/02/2019

For the first time in centuries, the compbad in Greenwich, they will directly target True North: an epic coincidence of time and magnetism This has not happened for about 360 years.

This fortuitous event, which will occur in the coming days, recalls the way in which the Magnetic North Pole of the Earth It changes constantly, unlike the geographic North Pole of the Earth.

The angular difference between these two different points is called magnetic declination and is controlled by scientists so that global mapping and navigation systems work properly.

For hundreds of years, due to the displacement of the magnetic north pole, the decline was negative, meaning that the Greenwich compbad needles were pointing to the west of the geographic north.

The invisible line connecting the magnetic north and south poles of the Earth (and representing a zero declination) has moved westward at about 20 kilometers per year.

At this rate, this month will go through the historic site of the Royal Observatory of Greenwich. "At some point in September, the line will be zero in Greenwich," Ciaran Beggan, a geomagnetism researcher at the British Geological Survey (BGS), told Science Alert. Observatory that geographic and geomagnetic coordinate systems will coincide with this location ".

Then, the line will follow its course. "By 2040, all the compbades will probably be directed to the true north east," he explained.