Glossary key termsAxis - An imaginary line passing through the North and South Poles, tilted at 23.5 degrees, around which Earth rotates.Rotation - The spinning of Earth on its axis, taking approximately 24 hours and causing the cycle of day and night.Shadow - A dark area formed when an object obstructs light, varying in size and direction based on the light source's angle.Nighttime - The period of darkness on Earth's side facing away from the sun, occurring between dusk and dawn.Daytime - The period of sunlight on Earth's side facing the sun, occurring between sunrise and sunset.