1. What is Magnetic Declination?

Magnetic declination is the angle between magnetic north (the direction the compass points) and true north. This angle varies depending on your location on Earth and changes over time due to shifts in Earth's magnetic field.

2. How Does the Calculator Work?

The calculator uses the following formula:

Where:

• \( X \) — North component of the magnetic field (nT)
• \( Y \) — East component of the magnetic field (nT)

Explanation: The arctangent function calculates the angle whose tangent is the ratio of Y to X components, giving the declination from true north.

3. Importance of Declination Calculation

Details: Accurate declination calculation is crucial for navigation, surveying, and any application requiring precise orientation. It helps correct compass readings to true north.

4. Using the Calculator

Tips: Enter the north (X) and east (Y) components of the magnetic field in nanoteslas (nT). The calculator will compute the declination angle in degrees.

5. Frequently Asked Questions (FAQ)

Q1: What units are used for X and Y components?
A: The components should be entered in nanoteslas (nT), which are standard units for measuring Earth's magnetic field components.

Q2: How precise is this calculation?
A: The calculation is mathematically precise, but actual field measurements may have instrument error. Results are shown to 4 decimal places.

Q3: What does a positive/negative declination mean?
A: Positive declination means magnetic north is east of true north, negative means it's west of true north.

Q4: How often does declination change?
A: Declination changes slowly over time due to secular variation in Earth's magnetic field, typically a few minutes per year.

Q5: Is this calculation location-specific?
A: Yes, the X and Y components vary by location, so you need local magnetic field measurements for accurate declination.