Eratosthenes' postulate of a curved Earth is based on parallel Sun rays

The Achilles' heel of the heliocentric globe model.

According to mainstream science, 2200 years ago, Eratosthenes calculated the circumference of the Earth (as 24,901 miles) based on Sun angles and stick shadows. Which is the basis of the heliocentric globe model to this day.

As we know, many real-world observations prove that we can see far beyond the official "distance to the horizon" calculations of the globe model. To explain this, scientists say that what we see is a mirage and is caused by atmospheric refraction. But Eratosthenes never took into account the refraction of light in the atmosphere when calculating the angle of the sun, instead he (or the proponents of the globe) curved the Earth's surface to match the math with real-world observations.

So the question is, why don't they replace the dimensions of the Earth with a larger globe? Because...they simply can't...and they never will...because if they did, the math wouldn't fit the real-world observations which would destroy their model.