Purchase Solution

Panet retrograde motion - Earth-center and Sun-center

Not what you're looking for?

Ask Custom Question

How can planet retrograde motion be explained by the Earth-center hypothesis and by the Sun-center hypothesis.

Purchase this Solution

Solution Summary

In 699 words, this solution discusses planetary motion as opposed to star motion, and how this can be explained using both the Earth-center and Sun-center hypotheses.

Solution Preview

As you know, to an observer on earth, the entire sky appears to rotate from East to West during the course of a night (actually during the day too, but the only celestial object we can see during the day is the sun), which is really due to the fact that the Earth is rotating.

Now imagine that, at the same time every night for a year--say, at midnight--you were to go outside and make a perfect sketch of every object you could see in the sky: stars and planets.

What you would soon notice is that, while the stars appear to be in the same position relative to one another *every night*, the planets actually change their positions from night to night. That is, the planets appear to *move* relative to the stars, and this motion is fast enough to become noticeable after only a few days of observations in most cases.

What we mean by "retrograde motion" is this: *most* of the time, this relative motion of the planets with relative to the fixed stars is West to ...

Purchase this Solution


Free BrainMass Quizzes
Introduction to Nanotechnology/Nanomaterials

This quiz is for any area of science. Test yourself to see what knowledge of nanotechnology you have. This content will also make you familiar with basic concepts of nanotechnology.

Variables in Science Experiments

How well do you understand variables? Test your knowledge of independent (manipulated), dependent (responding), and controlled variables with this 10 question quiz.

The Moon

Test your knowledge of moon phases and movement.

Intro to the Physics Waves

Some short-answer questions involving the basic vocabulary of string, sound, and water waves.

Basic Physics

This quiz will test your knowledge about basic Physics.