In alt.home.repair, on Thu, 11 Oct 2018 00:47:18 -0400, Clare Snyder
wrote:

On Wed, 10 Oct 2018 23:41:03 -0400, micky
wrote:


This is from Wikip's article on Gemini 8:

Perigee (min): 159.8 kilometers (86.3 nautical miles)

Why are there nautical miles but no nautical kilometers?


Why shouldthere be? A naughtical mile is equivalent to 1 degree of
latitude. A statute mile is an arbitrary measurement.
The origins of the meter go back to at least the 18th century. At that
time, there were two competing approaches to the definition of a
standard unit of length. Some suggested defining the meter as the
length of a pendulum having a half-period of one second; others
suggested defining the meter as one ten-millionth of the length of the
earth's meridian along a quadrant (one fourth the circumference of the
earth). In 1791, soon after the French Revolution, the French Academy
of Sciences chose the meridian definition over the pendulum definition
because the force of gravity varies slightly over the surface of the
earth, affecting the period of the pendulum.

Great explanation.

Why add another arbitrary measurement to the mix????

I don't know, but sometimes they seem to do that just to complicate my
life.