Correct Option
The correct option isWe always see the same side of the moon.
Explanation
The visibility of the Moon from Earth is governed by the phenomenon of synchronous rotation, also known as tidal locking. This gravitational interaction ensures that the Moon's rotational period and its orbital period around Earth are synchronized.
Option Analysis
- We always see the same side of the moon. is Correct: The Moon rotates on its axis at approximately the same rate that it revolves around the Earth. Both motions take about 27.3 days to complete. Because these periods are identical, the same hemisphere (the "near side") is always directed toward Earth.
- We see different sides of the moon every night. is Incorrect: Observers on Earth do not see different sides of the Moon each night. While a phenomenon called libration allows us to see slightly more than 50% of the surface over time, the general face of the Moon remains constant.
- The moon does not rotate on its axis. is Incorrect: The Moon does rotate on its axis. If the Moon did not rotate, different sides of its surface would become visible to Earth as it moved through its orbit. It rotates exactly once every time it circles the Earth.
- The moon rotates faster than it revolves around the Earth. is Incorrect: The Moon does not rotate faster than it revolves; the angular speed of rotation matches the angular speed of revolution. This synchronization is the reason for the fixed orientation relative to Earth.
Key Takeaway: The Moon exhibits synchronous rotation, meaning its time of rotation on its axis is equal to its time of revolution around the Earth (approx. 27 days), causing us to see only one side.