Question

According to Kepler's model of the solar system, what is retrograde motion is caused by? Select one:

a. epicycles.
b. the daily turning of the celestial sphere.
c. the difference in orbital speed of Earth and other planets.
d. the changing speed of the Sun.
e. the Earth's rotation.

Answer 1

Retrograde motion in Kepler's model of the solar system is caused by the difference in orbital speed of Earth and other planets.

Step-by-step explanation:

Retrograde motion in Kepler's model of the solar system is caused by the difference in orbital speed of Earth and other planets. When Earth overtakes another planet in its orbit, the apparent motion of the planet appears to reverse temporarily, giving the illusion of retrograde motion. This occurs because Earth's closer proximity to the Sun causes it to move faster in its orbit compared to the other planets.