Question

Saturn is the sixth planet from the Sun. Diagrams of Saturn's elliptical orbit around the Sun with focal points marked are shown below. Saturn has an orbital period of 29.46 years. Which diagram best represents the relative motion of the planet Saturn and the Sun?
A.



B.



C.



D.

Answer 1

To determine which diagram best represents the relative motion of Saturn around the Sun, we should consider the characteristics of an elliptical orbit. Here are a few key points that a correct diagram should demonstrate:

1. **Elliptical Shape**: Saturn's orbit is elliptical, meaning it isn't a perfect circle but more of an elongated oval.

2. **Foci of the Ellipse**: In an elliptical orbit, the Sun is located at one of the two foci of the ellipse. The distance from the Sun changes as Saturn orbits it.

3. **Speed Variation**: According to Kepler's laws, a planet moves faster in its orbit when it is closer to the Sun (perihelion) and slower when it is farther away (aphelion).

4. **Orbital Period**: Since Saturn takes about 29.46 years to complete one orbit, the diagram must allow for this relatively long orbital period in its scale.

5. **Direction of Motion**: The orbit should indicate the direction of Saturn’s motion around the Sun.

If you can describe the features of the diagrams (A, B, C, D) you have, I can help you determine which one best matches the characteristics of Saturn's orbit.