Earth, Sun and Moon Study Guide (SOL 4.6)

Vocabulary practice flashcards covering Virginia Science SOL 4.6: rotation, revolution, day and night, causes of seasons, the four major Moon phases, tides, and the relative size and makeup of the Earth, Sun, and Moon.

Axis

An imaginary line through Earth from the North Pole to the South Pole.

Rotation

Spinning on an axis. One rotation of Earth takes about $24\,\text{hours}$ and creates one day and one night.

Revolution

One trip around another object. Earth travelling around the Sun in an orbit takes about $365\,\text{days}$, or $1\,\text{year}$.

Orbit

The path one object takes around another object in space.

Day and Night

The daily cycle caused by Earth's rotation; the half of Earth facing the Sun experiences day, while the half facing away experiences night.

Cause of Earth's Seasons

The tilt of Earth's axis as it revolves around the Sun; seasons are not caused by Earth moving closer to or farther from the Sun.

Summer

The season that occurs when our half of Earth leans toward the Sun, causing sunlight to hit directly and days to be long.

Winter

The season that occurs when our half of Earth leans away from the Sun, causing sunlight to hit at a slant, spread out, and days to be short.

Phase

The shape of the lit part of the Moon that we can see from Earth.

Reflect

To bounce light off a surface; the Moon does not create its own light but reflects light from the Sun.

New Moon

The phase where the Moon is between Earth and the Sun, and its lit side faces completely away from Earth so it cannot be seen.

First Quarter

The Moon phase where the right half of the Moon is lit as viewed from Virginia.

Full Moon

The Moon phase where Earth is between the Sun and the Moon, allowing us to see the whole lit side.

Third Quarter

The Moon phase occurring after a full Moon where the left half of the Moon is lit.

Cause of Moon Phases

Seeing different amounts of the Moon's sunny side as it revolves around Earth; phases are not caused by Earth's shadow.

Gravity

A pulling force between objects, such as the Moon pulling on Earth's oceans.

Tide

The daily rise and fall of the ocean caused by the pull of the Moon's gravity on Earth's waters.

Highest High Tides

The largest ocean bulges that occur during new and full Moons, when the Sun, Earth, and Moon line up.

Sun (Makeup and Relative Size)

A star made of hot gases; it is the largest of the three bodies (comparable in scale to a beach ball).

Earth (Makeup and Relative Size)

A planet made of rock with liquid water and air that supports life; it is medium-sized compared to the Sun and Moon (comparable to a baseball).

Moon (Makeup and Relative Size)

A natural satellite made of rock with no air and no liquid water; it is the smallest of the three bodies (comparable to a golf ball).