What term describes the spinning motion of a planet on its axis?

• A. Seasons
• B. Rotation
• C. Revolution
• D. Lunar Eclipse

Answer: (B)

Rotation is the spinning of a planet on its axis, the imaginary line that runs through its center. As the planet turns, different parts face toward or away from the Sun, creating day and night. A full rotation takes about 24 hours, which is why we have a daily cycle. This is different from revolution, which is the planet’s path around the Sun and takes about a year to complete. Seasons arise mainly from the tilt of the planet relative to its orbit, changing how sunlight hits each hemisphere over the year. A lunar eclipse is a distinct event where Earth sits between the Sun and the Moon, not a description of spinning on its axis. So the spinning motion on its axis is rotation.