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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.
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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.
What is one indication that a planet may exist near a distant star?
If a distant star has a slight back and forth motion then it may be located near a planet. The gravitational force of the planet will cause the star to move.
The term used to describe the motion of a planet?
A better approach is to try to make more general the characteristic of a body to resist change in motion. The characteristic is called inertia. kinematics
Which of Hamlet's plans does Claudius say is most retrograde to our desire?
"As for your intent in going back to school in Wittenberg, it is most retrograde to our desire." Act I Scene 2.
What are the ratings and certificates for Retrograde - 2004?
Retrograde - 2004 is rated/received certificates of: Finland:K-15 Germany:16 (DVD) Iceland:16 Netherlands:12 Singapore:NC-16 South Korea:15 Sweden:15 UK:15 USA:R
The apparent westward movement of a planet is known as?
retrograde motion
What planet has retrograde motion?
venus
What is retrograde motion as applied to a planet?
The "apparent" reverse or backwards motion of a planet as observed from Earth. The innermost planets appear to have a retrograde motion when viewed from Earth.
The planet rotates by retrograde motion?
Venus.!
This planet rotates by retrograde motion?
venus
When a superior planet is in the middle of its retrograde motion what planetary configuration is it in?
Superior planets are in opposition when in the middle of their retrograde motion.
What is it called when a planet rotates counterclockwise?
Retrograde motion.
What planet has a moon that exhibits retrograde motion?
neptune
How did Copernicus explain the retrograde motions of the planets?
All the models explain retrograde motion because it is such an obvious phenomenon. In Copernicus's model an outer planet goes into retrograde motion when the inner planet overtakes it so that it appears from the inner planet to be going backwards along the ecliptic.
What planet has no satellites and a retrograde revolution?
Venus has no natural satellites and retrograde motion (orbits opposite direction it rotates).
What is it called when a planet appears to move bacwards in is orbit?
"retrograde motion"
How can you tell if a planet is in retrograde?
You observe its motion, with respect to the background stars.
