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The distance of one degree of latitude near the Equator on the Earth’s ellipsoid is…
  • A
    more than 60 NM.
  • B
    more than 60 NM but less than 61 NM.
  • C
    less than 60 NM.
  • D
    60 NM.

For navigation purposes, the Earth is considered to be a perfect sphere and we consider every degree of Latitude to be 60 NM.

However, in reality, the Earth is an irregularly shaped ellipsoid, flattened at the poles and bulged at the Equator. The length of a degree of Latitude varies with Latitude - being less than 60 NM at the Equator and increasing towards the Poles. It is only 60 NM around the parallel of 45ºN/S.

A degree of Latitude is shorter at the Equator than at the poles:

  • 0º => Approx. 59.7 NM
  • 45º => 60 NM
  • 90º => Approx. 60.3 NM

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