Questions tagged [ptolemy]

Ptolemy was an astronomer, mathematician, and geographer of Greek descent who flourished in Alexandria during the 2nd century CE.

Filter by
Sorted by
Tagged with
1
vote
1answer
69 views

The Rejection of Solid Orbs by Geo-Heliocentric (Tychonic) model of the solar system

Some sources (modern sources, and Kepler himself) claim that in his Geo-Heliocentric (Tychonic) model, Tycho Brahe saw that the orbs of the Sun and Mars intersect, and this was one of the reasons ...
0
votes
1answer
81 views

Was Fourier inspired by Ptolemy?

Ptolemy invented a system to describe the periodic motion of the planets by epicycles. Fourier did something similar for periodic motion in mechanics. Every such motion can be thought of as ...
2
votes
0answers
90 views

On Ptolemy climes

Reading Dante's Comedy, I was interested in understand a little bit how medieval geography worked, so I decided to have a look at Edward Luther Stevenson's translation of Ptolemy's Geographia. I've ...
2
votes
3answers
158 views

Has anyone explored Ptolemy's epicycles as an early form of Fourier analysis?

Whilst researching science in the ancient world, I came across an observation, which unfortunately I did not make a note of, and so cannot credit, that Ptolemy's epicycles were an early form of ...
5
votes
1answer
363 views

Did Ptolemy and other Greek scientists actually measure the distance to the Sun?

According to Subhash C. Kak: Early Theories on the Distance to the Sun: “Pancavimsa Brahmana states that the heavens are 1000 earth diameters, de, away from the earth. The sun was also taken to be ...
6
votes
2answers
601 views

Where did Ptolemy compare the Earth to the distance of fixed stars?

I read the following in C. S. Lewis, Miracles (page 77-8) The immensity of the universe is not a recent discovery. More than seventeen hundred years ago Ptolemy taught that in relation to the ...
2
votes
2answers
1k views

How did Ptolemy calculate the distance to the Moon?

I've read somewhere that Hipparchus measured the distance to the Moon using the lunar and solar eclipse and obtained a value of around 67.3 Earth radii. It also says that soon after Ptolemy gave a ...
55
votes
3answers
2k views

What is Ptolemy holding in this picture?

I would like to know the name of the device Ptolemy is holding in the following picture.