Apparent movement

Apparent movement caused in part by the actual movement of celestial bodies along the ecliptic and the progress of Earth itself.

Interesting facts:

This explains why it seems that a remote planet “slows down” or “stops” and then appears to “move backward” in front of the stars—at least this is how it seems when viewed from a particular part of Earth’s orbit. We say that the planet is either stationary or retrograde.

However, we see the orbits of Mercury and Venus from the outside, and when they move toward the other side of the sun compared to us, we sometimes perceive their motion as retrograde.

Neither the sun nor the moon can move backward and become retrograde.

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