Quick Answer
To differentiate between true north and magnetic north, use a compass with a declination adjustment and observe the needle's direction, or use a GPS device and calculate the declination. Alternatively, note the position of the sun at solar noon and use a sun compass. True north is also marked on many maps.
Understanding Magnetic Declination
Magnetic declination is the difference between magnetic north and true north. It varies depending on your location, with some areas having a declination of up to 20 degrees. To find the declination in your area, consult a declination map or use a GPS device with a built-in declination calculator. Adjusting your compass for declination can make a significant difference in navigation accuracy.
Using a Compass with Declination Adjustment
Most modern compasses come with a declination adjustment feature. This allows you to set the declination for your area and get an accurate reading of true north. To use this feature, follow the manufacturer’s instructions and adjust the declination to the correct value for your location. This will ensure that your compass is pointing towards true north.
Using a Sun Compass
A sun compass is a simple navigation tool that uses the position of the sun to find true north. To use a sun compass, note the position of the sun at solar noon (when the sun is highest in the sky) and draw a line between the sun and a vertical object, such as a tree. The line will point towards true north. This method is most accurate when the sun is high in the sky and the atmosphere is clear.
Find more answers
Browse the full Q&A library by topic, or jump back to the topic this question belongs to.