Distance of the moon, accoring to Ptolemy

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In summary, according to Ptolemy's geocentric model of the universe, the distance of the moon from the Earth was believed to be constantly changing. Ptolemy proposed that the moon's orbit was not a perfect circle, but rather an eccentric ellipse, causing its distance from the Earth to vary. This theory was later proven incorrect with the development of the heliocentric model by Copernicus, which placed the sun at the center of the solar system. However, Ptolemy's work laid the foundation for further studies and understanding of celestial motion.
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The Wikipedia article on the moon says ithat "Ptolemy (90–168 AD)" calculated the distance of the moon as 59 times the Earth's radius and a diameter, which is about the modern value.

But Wikipedia doesn't say how Ptolemy did that.

An article at http://www.eso.org tells how to calculate the moon's distance on the basis of the moon's apparent position, from two different locations on earth, during a solar eclipse, but it seems likely Ptolemy did not use this method.

Does anyone know how Ptolemy, some 2,000 years ago, might have calculated the distance to the moon? Just wondering . . .
 
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1. What did Ptolemy believe about the distance of the moon?

Ptolemy believed that the moon was located at a fixed distance from the Earth and that it did not move closer or farther away from us.

2. How did Ptolemy calculate the distance of the moon?

Ptolemy used a geometric method called parallax to calculate the distance of the moon. He compared the angle of the moon's elevation at two different locations on Earth to determine its distance from the Earth.

3. What was Ptolemy's estimated distance of the moon?

Ptolemy's estimated distance of the moon was about 59 Earth radii, which is equivalent to approximately 238,000 miles.

4. Was Ptolemy's calculation of the distance of the moon accurate?

No, Ptolemy's calculation was not accurate. It was later found to be off by about 40% due to the limitations of the instruments and methods available at that time.

5. How does Ptolemy's belief about the distance of the moon differ from modern understanding?

Ptolemy believed that the distance of the moon was fixed and did not change, while modern understanding shows that the moon's distance from Earth varies due to the elliptical shape of its orbit. Additionally, modern technology allows for more precise measurements, resulting in a much more accurate understanding of the moon's distance.

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