4 ms·
It depends what geoid model you use, and once you go down that rabbit hole it depends on the local gravitational field which is affected by things like mountain
by snovv_crash 3y ago
It depends what geoid model you use, and once you go down that rabbit hole it depends on the local gravitational field which is affected by things like mountains, not only the centrifugal effect.
For a sailor in the 16th century, assuming a sphere was perfectly adequate when combined with 1 degree = 60 nautical miles.
- defrost 3y agoThe actual shape of the Earth is independent of which ellipsoid model is chosen to locally or globally "best match" the actual shape. The geoid model is the surface of gravitational equipotential and is a "shape of the gravitational field" not a "shape of the physical earth". If we were discussing 16th century sailors rather than 21st century aviation you might have had a point.
- snovv_crash 3y ago...isn't that pretty much what I said? The origin of nautical miles is from 16th century sailors. And 21st century aviation doesn't need anything more accurate than WGS84. The people who need custom geoid models and local coordinate systems are surveyors.