What Is This Tool?
This tool allows you to convert measurements from Earth's polar radius, a geodetic length representing the distance from Earth's center to the mean geographic pole, into the US survey fathom unit used in nautical contexts.
How to Use This Tool?
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Enter the value in Earth's polar radius units you want to convert.
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Select the target unit as fathom (US survey) [fath].
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Click the convert button to get the result in fathoms (US survey).
Key Features
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Converts Earth's polar radius values to fathom (US survey) units accurately based on defined conversion rates.
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Supports key use cases in geodesy, satellite orbit modelling, hydrographic surveying, and maritime navigation.
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Online and easy to use with simple input fields and clear output results.
Examples
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1 Earth's polar radius equals 3,475,920.9790277 fathoms (US survey).
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0.5 Earth's polar radius converts to 1,737,960.48951385 fathoms (US survey).
Common Use Cases
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Defining the semi-minor axis of geodetic ellipsoids like WGS84 for mapping and GPS applications.
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Modelling satellite orbits and interpreting satellite altimetry data.
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Relating large geodetic reference measurements to nautical lengths in maritime navigation and hydrographic surveys.
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Converting legacy hydrographic survey data recorded in US survey fathoms to metric units.
Tips & Best Practices
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Verify unit consistency when working with US survey fathoms versus international fathoms due to slight differences.
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Use this conversion primarily for integrating earth-shape data with nautical charts and legacy survey records.
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Be cautious when interpreting measurements since Earth's polar radius is very large and may not suit all practical maritime applications.
Limitations
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Earth's polar radius is extremely large and not generally used for direct fathom measurements in maritime contexts.
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The US survey fathom is not identical to the international fathom, requiring careful unit handling.
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Legacy survey data in US survey units may include rounding or definition differences compared to metric standards.
Frequently Asked Questions
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What is Earth's polar radius?
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Earth's polar radius is the distance from Earth’s center to the mean geographic pole along the rotation axis, representing the semi-minor axis of a reference ellipsoid like WGS84.
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What is a fathom (US survey)?
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A US survey fathom is a nautical length unit equal to exactly 6 US survey feet, used primarily in hydrographic surveys and maritime measurements.
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Why convert Earth's polar radius to fathoms (US survey)?
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Converting these units helps relate large geodetic measurements to nautical length units for integrating earth-shape data with historical nautical charts and maritime navigation.
Key Terminology
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Earth's polar radius
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The distance from Earth's center to the mean geographic pole along the rotation axis, used as the semi-minor axis in geodetic ellipsoids.
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Fathom (US survey) [fath]
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A non-SI nautical length unit equal to 6 US survey feet, used for measuring depths and line lengths in hydrography.
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WGS84
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A widely used geodetic reference ellipsoid representing Earth's shape, defining Earth’s polar radius.