I think I am not the only one this week to wonder about mileage. (Because of Artemis, of course, not gas prices.)
Evidently measuring statute miles in feet and inches is deficient. I suppose that’s why we ended up with terms like “a country mile” and “as the crow flies.” If you’re navigating huge expanses, like an ocean, you need something more exact. Can’t put a tape measure on the ocean.
At any rate, after rational people decided the earth was not flat, they covered the globe with grid lines of latitude and longitude. And I’m quoting here, because this is math: ”A Nautical Mile is the distance you cover when you travel along a longitude, within a slice of latitude that’s one-sixtieth of a degree (1/60).”
It’s longer than a statute land mile, but close enough they can both still use the word “mile”.
So the moon is about 200,000 nautical miles (nm) away. Mars is 30 million nm away. Pluto (I still count you Pluto) is 231 billion nm away.
Or, in light terminology, Mars is 19 light-minutes away, Pluto is almost 5 light-hours away.
Seems like we need a meansurement between nautical miles and light-years. And so there is, astronomical units, which I copied freely from NASA, because there are no NASA copyrights because U.S. taxes paid for it.

I give that to fellow members of the globe to make up for the way I have utterly disregarded kilometers in this post.
So instead of having a fraction of latitude and longitude be the standard, the distance from the Earth to the Sun is the standard. That seems very earth-centric. We’ll probably meet people orbiting Alpha Centauri and find the use kilometers too.









