It's a reference to Justin_K's earlier statement "a Knot is standard for navigation world wide because the unit is standardized on earth's size".
If that justifies knot then it also justifies kilometers, because it too was originally standardized on the earth's size.
Neither are exactly the size as originally defined.
A modern knot is 1852 meters. One minute of latitude is "about 1,855.325 m on the WGS 84 ellipsoid" says https://en.wikipedia.org/wiki/Nautical_mile. The difference is 0.16%.
If that justifies knot then it also justifies kilometers, because it too was originally standardized on the earth's size.
Neither are exactly the size as originally defined.
A modern knot is 1852 meters. One minute of latitude is "about 1,855.325 m on the WGS 84 ellipsoid" says https://en.wikipedia.org/wiki/Nautical_mile. The difference is 0.16%.
A quarter of the Earth is:
The difference is 0.19%.