Enjoy the short 10 min vid

He is making a poor mathematical assumption.

We are not talking about distances we are only talking about the angle from where the ship is in relation to the star.

Look at what was drawn at :43.  That is not how it should be drawn. 

It should have been drawn like this, so it really doesn't matter if the earth is curved or flat.  The geometry would work the same.

That makes no sense.  If the earth is a ball, and ship A is at the top of the ball (i.e. close to the US) and ship B is at the bottom of the ball (i.e. China), how can both ships be equally distant from the same star?

If the star can be seen from both the US and China, and it is half way between the two and high enough in the air where the curve would not matter, then it could be equally distant.  And when we are talking about celestial navigation it is more about what it looks like then actual distances.  The person does not need to know exactly how far the star is to make the navigation work. 

Here is how star navigation works.  The information comes from a google search.

"A star chart functions in navigation by providing a visual map of the night sky, allowing navigators to identify specific stars and measure their position relative to the horizon, which then enables them to calculate their latitude and longitude based on the known positions of those stars at a given time and location; essentially, by comparing the observed position of a star on the chart to its actual position in the sky, a navigator can determine their geographical coordinates."

I am sorry that I am not explaining it very well.  

The way the original OP video was drawing the geometry was incorrect and I just wanted to bring that to peoples attention.  I personally believe that from this information you can't determine flatness or curve of the earth.  This is why most calculations are done as if the earth is flat because it is just easier to do the calculation.  Since most of the earth has been mapped we already know distances from one place to another so we just flatten the curve out and then measure.

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If the star can be seen from both the US and China, and it is half way between the two

What if it's NOT halfway between the two?  That's my question.

Actually that wasn't your question.  The star would have to be in the middle.  Else they would have to use a different star that is in the middle.

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And when we are talking about celestial navigation it is more about what it looks like then actual distances.  The person does not need to know exactly how far the star is to make the navigation work.

  The distance of the star, determines where it is in relation to the horizon, as you describe below.

Yes and everything has to be recalculated throughout the trip because the sky changes over head as you move in one direction.

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"A star chart functions in navigation by providing a visual map of the night sky, allowing navigators to identify specific stars and measure their position relative to the horizon,

The north star, for example, doesn't move.  So this star will be in DIFFERENT positions on the horizon (using a globe model), if you're in the US vs China (i.e. china can't see the north star).  But if the earth were a spinning globe, everyone should be able to see the north star, at some point during the day, because a) the north star doesn't move and b) the spinning earth would be a like a clock which would round every number, at some point during the day.

This statement confuses me.  The Sphere Earth if it is spinning, spins like a top.  The earth is hanging in all the stars, so the star map for the Northern Hemisphere is different than the star map of the Southern Hemisphere.

If the Earth was flat then it would be like a sandwich with the stars on top and the Earth on the bottom.  The stars would not change position.  So Orions belt would always be in the same place in the sky no matter what time of day.  Yet is is not.  Something is moving.

A FE model will show the north star in the exact, same spot on the horizon, no matter where you are in the world.  Because everyone is looking up.  That's why china can't see the north star.  Because the earth doesn't move.

This statement confuses me.  If the north star is always in the same spot, then why would China not see it, if the Earth is flat?

Initially the 'size of the universe' made me doubt the experiments - how could something a quadzillion, billion light years across do a daily revolution around the earth - but now it's one of the things that's helping me toward a much smaller, enclosed, flat earth model.  I.e. the biblical cosmology.

If the Earth was flat then it would be like a sandwich with the stars on top and the Earth on the bottom.  The stars would not change position.  So Orions belt would always be in the same place in the sky no matter what time of day.  Yet is is not.  Something is moving.

The inteferometer experiments of Michelson-Morley showed the earth was not moving.  They were later run again by Michelson-Gale, and later Sagnac also, which showed a daily rotation so yes, something is definitely moving but the evidence shows it's the star field around a fixed earth.

Does the Earth not moving mean it is flat? I am not sure that the belief in shape, leads to a decision about the movement.

Does the Earth not moving mean it is flat? I am not sure that the belief in shape, leads to a decision about the movement.

The classical models (e.g. Aristotle, Ptolemy) had a stationary, globe earth.  This was what Catholics believed for most of our history, although as a matter of science rather than faith.  

No, that's the point.  Not everything in the sky changes.  The north star, in the northern hemisphere, NEVER moves.  The constellations do move, which is why there are various constellations at various times of the year.

The constellations move in relation to the North star.  I can always find the North star because it is part of the little dipper.  That never changes.  The North star is not always in the same spot overhead at night.

No, the Sphere earth spins like a top AND ALSO spins like a rolling ball.  It spins in all directions, as it rotates around the sun.  If it only spun like a top (i.e. left to right) then some countries would never get sunshine. 
The constellations revolve around the earth.  The north star does not move.

See above.

Because the north star is much, much closer to earth than we're told.  It's not "billions of light years" away.  I'm not sure why China cannot see the North star, but it's a fact.

OK.  But if you take a point in California and a point in China and measure the distance about (6000 miles). A star that they both saw would only have to be 1804 miles above the earth. 

The problem with these discussions is that, *I assume* you are arguing based on some type of geocentric model, but you're explaining/quoting sources (i.e. google) which are heliocentric.  So your explanation is a hodge-podge of 2 diametrically opposed systems. 

I was just looking up how star maps were used.  I was not making a claim for any type of cosomology.  I am just saying the geometry is off, so I was trying to explain how.