British compasses have been WRONG for 360 years – but will finally point ‘true north’ this month
COMPASSES at Greenwich Observatory in London will soon be pointing true north for the first time in 360 years.
Most people don't realise that compasses are often slightly wrong because the 'true north' of the North Pole can be different to the Earth's magnetic north that compasses point to.
At some point over the next two weeks compasses in Greenwich will be pointing true north.
However, other parts of the UK may have to wait two more decades for the phenomenon to happen to them.
Compass needles create an angle between true north and magnetic north and this angle is called declination.
For the past few hundred years, compass needles have been pointing west of true north because the declination is currently negative.
The magnetic poles on Earth are not fixed in relation to its axis so as the Earth spins, magnetic north can move slightly.
True north is the direction along the Earth's surface to the North Pole and this never moves.
Expert navigators are used to compensating for declination when they are using a compass so they don't end up walking in the wrong direction.
It is thought that declination is now moving westwards at a rate of 12 miles per year, which means it will soon reach true north in the UK.
That means that in the next few weeks the compasses at The Royal Observatory Greenwich, which was founded in 1676, will point true north for the first time ever as the Earth's magnetic north aligns with it.
Zero declination will travel across the UK over the next couple of decades but by 2040 all compasses are likely to be pointing eastwards of true north.
This change for compasses shouldn't make a difference to your everyday life though as compasses and GPS will work as normal.
How do compasses work?
Here's the basics...
- Compasses are usually simple round objects that contain magnets
- This lightweight magnet is often reffered to as a needle because of its shape
- This magnet is usually balanced on a pivot so it can move around freely
- The needle marked 'N' always points north
- This is because the 'N' end of the magnet is attracted to the Earth's magnetic North Pole
- However, the magentic North Pole is moving as the Earth moves but the actual North Pole stays the same so sometimes compasses can be slightly wrong
- The actual North Pole is considered to be "true north"
- This can be accounted for by expert navigators and a compass should always take you in the general direction of North
TOP STORIES IN SCIENCE
In other news, China's lunar rover has discovered a mysterious 'gel-like' substance whilst roaming on the far side of the Moon.
These mind frazzling optical illusions may confuse you more than declination.
And, if you're often out navigating with a compass and need some new trainers then you're in luck as Nike has revealed new Back to the Future style sneakers.
How often do you use a compass? Let us know in the comments...
We pay for your stories! Do you have a story for The Sun Online Tech & Science team? Email us at [email protected]