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How was Ptolemy's idea of retrograde different from Copernicus' idea of retrograde motion?
We now understand that all the planets travel round the Sun, and a planet's retrograde motion happens as the Earth overtakes the other planet in its orbit. That was also Copernicus's view although we now use Kepler's theory, but on this point the two models are in agreement.
In Ptolemy's model the Earth is stationary in the centre, and the planets move on circles and epicycles, explained as follows.
Using Mars as an example and assuming the orbits of Earth and Mars are circular for simplicity, the Earth is at the centre and there is then a circle (or deferent) round it with a radius of 1.524 units. The epicycle is a smaller circle whose centre travels round the deferent in 687 days. The epicycle has a radius of 1.000 units and Mars travels round this in 365¼ days.
That was Ptolemy's geometric construction to explain the motion of Mars, and the retrograde motion happens when Mars on its epicycle moves close to the Earth.
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What does a planet do when in retrograde motion?
Nothing special. The idea of "retrograde motion" is a trick of perspective; nothing actually goes "retrograde". Here's how it works. We usually talk about Mars when referring to "retrograde" motion, but it happens (to a lesser extent) to all of the outer planets. All the planets orbit the Sun in the same direction (counterclockwise as seen from high above the Earth's north pole). Nothing ever turns and goes the other way. Closer-in planets orbit faster than further-out planets. When Mars goes retrograde, what is really happening is that the Earth is about to overtake Mars in our respective orbits, and move ahead of it. Mars is moving more slowly, and as the Earth passes Mars, Mars SEEMS TO move backwards. It's just as if you were jogging on an inner lane on the track and you pass somebody in an outer lane. The other jogger isn't moving backwards; it just seems that way because you are moving faster, and getting ahead of him.
How does a car jack work?
There are several different types, but they all reduce to forms of levers where a large-weak motion is converted into a small-strong motion.
How much do nachos cost at Rave motion pictures?
3 dollars NOT 3 Dollars person Above. The current Nacho Price at my Rave Motion Pictures is $6.50. Far different than the $3.00 stated above.
Where do actors act?
Actors work in many different places.Actors work on stage, radio, television, video, and in motion picture productions.
What is the difference between oscillating and rotational motion?
Rotational motion is motion which emulates that of the minute hand of a clock. Oscillating motion is motion which emulates that of the pendulum.
How did Copernicus explain the retrograde motions of the planets?
Copernicus explained the retrograde motions of the planets by proposing that the Earth and the other planets revolve around the Sun in circular orbits. He suggested that the appearance of retrograde motion was a result of the varying speeds at which the planets orbited the Sun.
The apparent westward movement of a planet is known as?
The apparent westward movement of a planet is known as retrograde motion. This phenomenon occurs when a superior planet passes Earth in its orbit, making it appear to move backward in the sky relative to the stars.
Major advantage of Copernicus' Sun-centered model over the Ptolemaic model?
It offered more natural explanation for the apparent retrograde motion of planets in our sky.
Copernicus ideas that supported his ideas about the sun being at the centre of the Solar System?
he was a polish priest scientist stated retrograde motion occured whenever earth passes around another plant gained acceptance from people had a much simpliar way to explain retrograde motion than Ptolemy
What caused Copernicus to challenge aristotles theories of planetary motion?
Copernicus challenged Aristotle's theories of planetary motion due to observations that didn't align with the geocentric model, particularly the retrograde motion of planets. Through his own observations and mathematical calculations, Copernicus proposed a heliocentric model where the Earth and other planets revolve around the Sun, providing a simpler explanation for the observed phenomena in the sky.
Why was it difficult for ancient astronomers to explain about the apparent retrograde motion?
Ancient astronomers found it difficult to explain apparent retrograde motion because they believed the Earth was at the center of the universe and all celestial bodies revolved around it in perfect circles. Retrograde motion conflicted with this geocentric model, leading to complex explanations involving epicycles and deferents. It wasn't until Copernicus proposed a heliocentric model that retrograde motion could be better understood as an illusion caused by the relative speeds and orbits of planets.
Was retrograde motion a theory?
Retrograde motion describes something by definition. It is not and has never been a theory.
What are the similarities beween Copernicus' model of the universe and Ptolemy's model of the universe?
Both Copernicus' and Ptolemy's models aimed to explain the motion of celestial bodies in the sky. However, Copernicus placed the Sun at the center of the universe, while Ptolemy's model had Earth at the center. Both models used the concept of epicycles to explain the retrograde motion of planets.
What is the difference between prograde and retrograde?
Prograde motion is a counter-clockwise motion or west to east, retrograde motion is clockwise motion or east to west.
How was Copernicus' idea of planet movement different from ptolemy's?
Copernicus proposed a heliocentric model, where planets revolve around the sun, while Ptolemy's geocentric model placed Earth at the center of the universe with planets orbiting around it. Copernicus' model helped to explain retrograde motion more simply than Ptolemy's epicycles.
Which two planets have Retrograde motion?
Venus and Uranus have retrograde rotation.There are other meanings of retrograde motion, but retrograde rotation fits the question best.
What actors and actresses appeared in Retrograde Motion - 2013?
The cast of Retrograde Motion - 2013 includes: Thomas Denman
