Deferent and epicycle
Deferent and epicycle - Wikipedia
a geometric model used to explain the variations in speed and direction of the apparent motion of the Moon, Sun, and planets.
Epicycle | astronomy - Britannica
revolved around small circles called epicycles at a uniform rate while the centre of the epicyclic circle orbited Earth on a large circle called a deferent.
Epicycle in Astronomy & Meaning of Ptolemy - Study.com
The orbit an planet took around the earth is known as a deferent. An epicycle is an orbit revolving around a point on the deferent. As a planet rotates around ...
Eccentrics, Deferents, Epicycles, and Equants - MathPages
It needs to move somewhat faster when it is closer to the earth, and slower when it is further away. ... The new point was called the equant, which was located on ...
Ptolemy's geocentric model of the solar system | Britannica
He argued that planets move on two sets of circles, a deferent and an epicycle. This explained retrograde motion while keeping the planets in their circular ...
Ptolemy explained the apparent "looping motion" of the planets by placing the center of one rotating circle, called the epicycle, which carried the planet, on ...
The simplest form of such motion is called the epicycle-deferent model. In this model, the planet moves around a small circle called the epicycle whose ...
These circles were called "Epicycles", and the concentric spheres to which they were attached were termed the "Deferents". Then, the centers of the epicycles ...
Ptolemaic planetary system - UBC Theoretical Physics
The other feature is that while the epicycle lies in the plane parallel to the orbit of the sun (the ecliptic) the deferent does not, but lies in a plane ...
The deferent rotates around the Earth while the epicycle rotates within the deferent, causing the planet to move closer to and farther from Earth at different ...
What are epicycles, deferents, eccentrics, equants, etc.?
This circle is called deferent. A point moves on the deferent with constant angular velocity, this point is called the center of the epicycle, ...
Epicycles Explain Retrograde Motion - Astronomy Notes
As a planet moves around on its epicycle, the center of the epicycle (called the ``deferent'') moves around the Earth. When its motion ...
Mercury's meandering deferent - Seb Falk
Well, no, not really. Why not? Precisely because Ptolemy was not trying to model modern systems: the deferent and epicycle are not pretending to ...
Deferent | astronomy - Britannica
In the Ptolemaic system each planet revolves uniformly along a circular path (epicycle), the centre of which revolves around Earth along a larger circular path ...
Modelling retrograde motion: the theory of epicycles - cabinet
The deferent was a large circle with the earth as its centre, just like the orbits of the Sun and Moon. The deferent carried a second circle, the epicycle, ...
The Ptolemaic System: A Detailed Synopsis
Each planet revolves on a small circle (an epicycle) that in turn revolves on a larger circle (the deferent). The epicycle of the Moon is too ...
PHYS 1404 Epicycles and Deferents - YouTube
PHYS 1404 Epicycles and Deferents · AstroProf's Channel · PHYS 1404 Ancient Astronomy to the Middle Ages · How the Bizarre Path of Mars Reshaped ...
Orbits with Epicycles on a Deferent - Wolfram Demonstrations Project
Orbits with Epicycles on a Deferent ... This Demonstration shows the trajectory of a planet (orange disk) around an observer (blue circle) ...
Ptolemaic system - Institute and Museum of the History of Science
In this way, the epicycle, while moving at uniform velocity across the deferent, appeared to the observer on Earth as if it were moving at ...
Galileo - L07 Ptolemy COPERNICUS
P here represents the planet. The rotation on the deferent is traditionally taken to be counter clockwise as shown. The motion on the epicycle could be in ...