Marine Distance Calculator

Great Circle Distance Formula:

\[ Distance = \arccos(\sin(lat1) \times \sin(lat2) + \cos(lat1) \times \cos(lat2) \times \cos(lon2 - lon1)) \times 3440.065 \]

Latitude 1:

degrees

Longitude 1:

degrees

Latitude 2:

degrees

Longitude 2:

degrees

Distance:

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1. What is Marine Distance Calculation?

Marine distance calculation using the great circle method provides the shortest distance between two points on the surface of a sphere (Earth). This is essential for marine navigation as it represents the most efficient route between two locations.

2. How Does the Calculator Work?

The calculator uses the Great Circle Distance formula:

\[ Distance = \arccos(\sin(lat1) \times \sin(lat2) + \cos(lat1) \times \cos(lat2) \times \cos(lon2 - lon1)) \times 3440.065 \]

Where:

\( lat1, lon1 \) — Latitude and longitude of first point (in radians)
\( lat2, lon2 \) — Latitude and longitude of second point (in radians)
3440.065 — Conversion factor from radians to nautical miles

Explanation: The formula calculates the central angle between two points on a sphere and converts it to distance using the Earth's radius.

3. Importance of Marine Distance Calculation

Details: Accurate marine distance calculation is crucial for voyage planning, fuel estimation, ETA calculations, and ensuring safe and efficient maritime navigation.

4. Using the Calculator

Tips: Enter coordinates in decimal degrees format. Latitude ranges from -90° to 90°, longitude from -180° to 180°. Positive values for North/East, negative for South/West.

5. Frequently Asked Questions (FAQ)

Q1: What is a nautical mile?
A: A nautical mile is approximately 1.852 kilometers or 1.1508 statute miles, based on the circumference of the Earth.

Q2: Why use great circle distance instead of rhumb line?
A: Great circle distance provides the shortest path between two points on a sphere, while rhumb line maintains constant bearing but is longer.

Q3: How accurate is this calculation?
A: The calculation assumes a perfect sphere. For more precise results, ellipsoidal models like Vincenty's formulae can be used.

Q4: Can I use this for air navigation?
A: Yes, the great circle distance calculation is also used in aviation for the same reason - it provides the shortest route.

Q5: What's the maximum error in this calculation?
A: Using a spherical Earth model introduces about 0.3% error compared to ellipsoidal models, which is acceptable for most marine navigation purposes.