Solar day

Definition

A solar day is the time it takes for Earth to rotate once on its axis relative to the Sun, resulting in a full cycle from one noon to the next. It averages about 24 hours but can vary slightly due to Earth's elliptical orbit and axial tilt.

5 Must Know Facts For Your Next Test

1. The average length of a solar day is approximately 24 hours.
2. The solar day is slightly longer than the sidereal day, which is about 23 hours, 56 minutes.
3. Variations in solar days occur because of Earth's elliptical orbit and axial tilt.
4. A solar day serves as the basis for our standard timekeeping system.
5. The concept of a solar day is crucial for understanding diurnal cycles and daily human activities.

Review Questions

• How does a solar day differ from a sidereal day?
• What factors cause variations in the length of a solar day?
• Why is the concept of a solar day important for timekeeping?

Related terms

Sidereal Day: The time it takes for Earth to complete one rotation relative to distant stars, approximately 23 hours and 56 minutes.

Elliptical Orbit: Earth's slightly oval-shaped path around the Sun, influencing variations in the length of a solar day.

Axial Tilt: The angle (about 23.5 degrees) between Earth's rotational axis and its orbital plane, affecting seasonal changes and length of days.