The Earth's rotation on its axis causes different parts of the planet to face the Sun at different times, resulting in day and night.

The Earth completes one full rotation in 24 hours, so there is a 1-hour time difference for every 15 degrees of longitude.

During the spring and autumn equinoxes, the Sun is directly above the Earth's equator, resulting in equal amounts of daylight and darkness in both hemispheres.

The Moon's phases are caused by the different angles at which sunlight reflects off the Moon's surface as it orbits the Earth.

The summer solstice occurs around June 21st or 22nd each year and is characterized by the longest period of daylight in the Northern Hemisphere.

The spring equinox occurs around March 20th or 21st each year and is characterized by equal amounts of daylight and darkness in both the Northern and Southern Hemispheres.

One complete day on Earth, also known as a solar day, is approximately 24 hours long.

Refraction is the bending of light as it passes from one medium to another, such as from air to water or from water to air.

Seasonal variation refers to the gradual change in the length of day and night throughout the year due to the Earth's tilt and its orbit around the Sun.

The Moon's gravitational pull on Earth's oceans causes tides, resulting in the rise and fall of sea levels.

Twilight is the period of darkness between sunset and sunrise, during which the sky is partially illuminated by sunlight.

The Earth completes one full rotation on its axis in approximately 24 hours, which is the duration of one solar day.

A solar eclipse occurs when the Moon passes between the Earth and the Sun, blocking the Sun's light and casting a shadow on Earth.

The period of darkness between moonset and moonrise is referred to as night.

A lunar eclipse occurs when the Earth passes between the Sun and the Moon, blocking the Sun's light from reaching the Moon and causing it to appear dark.