Sea Distance Between Ports Calculator

Haversine Formula:

\[ d = \arccos(\sin(lat1) \times \sin(lat2) + \cos(lat1) \times \cos(lat2) \times \cos(lon2-lon1)) \times 3440 \]

Latitude of Port 1:

degrees

Longitude of Port 1:

degrees

Latitude of Port 2:

degrees

Longitude of Port 2:

degrees

Sea Distance:

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1. What is the Sea Distance Formula?

The sea distance formula calculates the great-circle distance between two points on the Earth's surface using their latitudes and longitudes. This calculation is essential for maritime navigation and route planning.

2. How Does the Calculator Work?

The calculator uses the spherical law of cosines formula:

\[ d = \arccos(\sin(lat1) \times \sin(lat2) + \cos(lat1) \times \cos(lat2) \times \cos(lon2-lon1)) \times 3440 \]

Where:

\( lat1, lat2 \) — Latitude of ports 1 and 2 (in degrees)
\( lon1, lon2 \) — Longitude of ports 1 and 2 (in degrees)
3440 — Radius of the Earth in nautical miles

Explanation: The formula accounts for the curvature of the Earth to calculate the shortest distance between two points on a sphere.

3. Importance of Sea Distance Calculation

Details: Accurate sea distance calculation is crucial for voyage planning, fuel estimation, ETA calculations, and maritime safety.

4. Using the Calculator

Tips: Enter coordinates in decimal degrees (positive for North/East, negative for South/West). Valid ranges are -90 to 90 for latitude and -180 to 180 for longitude.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is this calculation?
A: It provides good approximation for most navigational purposes, though actual sailing distances may vary due to currents, winds, and obstructions.

Q2: What's the difference between nautical miles and statute miles?
A: 1 nautical mile = 1.15078 statute miles. Nautical miles are based on Earth's circumference (1 minute of latitude).

Q3: Can I use this for air distance as well?
A: Yes, the same formula works for great-circle distance in aviation, though flight paths may be affected by air traffic regulations.

Q4: What coordinate format should I use?
A: Use decimal degrees (e.g., 34.0522°N = 34.0522, 118.2437°W = -118.2437).

Q5: Why 3440 for Earth's radius?
A: The mean radius of Earth is about 3440 nautical miles (6371 km or 3959 statute miles).