Why do we experience different seasons on Earth?

• A. Because Earth's rotation speed changes during different months.
• B. Because the Sun's energy output varies greatly during the year.
• C. Because Earth's axis is tilted relative to its orbital plane around the Sun.
• D. Because the distance between Earth and the Sun changes significantly throughout the year.

Answer: (C)

Verified step by step guidance

1. Understand that Earth's axis is tilted at an angle of approximately 23.5° relative to its orbital plane around the Sun. This tilt is the primary reason for the variation in seasons.
2. Recognize that as Earth orbits the Sun, different parts of the planet receive varying amounts of sunlight due to the tilt. This causes changes in temperature and daylight hours.
3. Learn that during the summer solstice in the Northern Hemisphere, the North Pole is tilted toward the Sun, resulting in longer days and more direct sunlight. Conversely, during the winter solstice, the North Pole is tilted away from the Sun, leading to shorter days and less direct sunlight.
4. Understand that the equinoxes (spring and autumn) occur when Earth's axis is not tilted toward or away from the Sun, resulting in nearly equal day and night lengths across the planet.
5. Clarify that the distance between Earth and the Sun does not significantly affect the seasons, as Earth's orbit is nearly circular. The tilt of Earth's axis is the dominant factor in seasonal changes.