What takes 365.25 days to complete?

What takes 365.25 days to complete?

• A. Orbit
• B. Rotation
• C. Revolution
• D. Precession

Answer: (C)

Take the idea that the number of days in a year comes from: rotation is spinning on Earth’s axis, while revolution is Earth moving around the Sun. The roughly 365.25 days is the time it takes for Earth to go all the way around the Sun—its orbital period. That completes one orbit, which we call a year. The path of that motion is the orbit, but the duration to finish it is the revolution. Precession is the slow wobble of Earth's rotation axis over a long timescale, not related to the length of a year. So the event that takes about 365.25 days to complete is Earth's revolution around the Sun.

Take the idea that the number of days in a year comes from: rotation is spinning on Earth’s axis, while revolution is Earth moving around the Sun. The roughly 365.25 days is the time it takes for Earth to go all the way around the Sun—its orbital period. That completes one orbit, which we call a year. The path of that motion is the orbit, but the duration to finish it is the revolution. Precession is the slow wobble of Earth's rotation axis over a long timescale, not related to the length of a year. So the event that takes about 365.25 days to complete is Earth's revolution around the Sun.