True North and Magnetic North line up in a rare occurrence

Northern Hemisphere Credit: ITV Weather

If you've ever been to the Greenwich observatory and stood on the Meridian line and held a compass, you'll know that True North and Magnetic north do not align.

Due to magnetic changes in the Earth's molton core, the Earth's magnetic field is constantly shifting and so does the location of the magnetic North Pole. For centuries navigators have needed to make continuous adjustments for the difference between True North and Magnetic North.

Over the last 150 years, the magnetic pole has crept north over 1000 kilometers. Scientists believe it moves around 10 kilometers a year and can even flip from pole-to-pole. In more recent years, the speed has increased to 40 kilometres a year and could even reach Siberia in a few decades.

But this month, for the first time in 360 years, True North and Magnetic North will finally line up. This occurrence is so rare that it hasn't happened since the Greenwich Observatory was built back in 1676!

The line pointing directly to the magnetic North Pole is known as the Agonic, and the angle between True North and Magnetic North is known as the declination, which is different depending on where you are on the planet.

Agonic line Credit: Chris Page

It means that if you're in and around the capital navigating with a compass, you won't need to make a correction. The Agonic will continue to pass across the UK for the next 15 to 20 years. There's no need to panic though, as this will have no effect to our daily lives.