flat, page-623

"But nobody is cutting up sphere earths like oranges and measuring angles to stars"

True enough. But with just the slightest education, you can use accepted principles and techniques and act as though you can.

And as a bonus... it works.

Since your google seems to broken, please. Use mine.

https://thenauticalalmanac.com/2017_Bowditch-_American_Practical_Navigator/Volume-_1/05-%20Part%203-%20Celestial%20Navigation/Part%203-%20Celestial%20Navigation.pdf

This link will tell you more than you'll ever want to know about celestial navigation. Funny thing. The text string "flat" appears twice in that 119 page extract. In neither case is it followed by "earth".

As an added bonus, this extract talks a little about the latitude errors introduced by using the angle to Polaris ... which in part comes down to the degree of precision you require.