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WHAT IS THE SUN?

• The Sun is an average-sized star made mostly of hydrogen and helium.

• It is the central and largest body in our solar system.

• The sun is a ball of hot gas that gives off energy.

PARTS OF THE SUN• Photosphere: The part of the Sun that gives off light energy.

• Chromosphere: The layer above the photosphere

• Corona: The outermost layer.

• Sunspots: Parts of the Sun that are darker because they are not as hot as the other parts of the sun.

• Prominence: An eruption on the Sun that looks like a ribbon of glowing gases.

• Solar flares: similar to volcanoes, give of forms of solar energy, a bright spot on the sun.

THE SOLAR SYSTEM

• The solar system is made of the Sun, its planets, moons, asteroids and comets

• Every object in the solar system revolves around the sun in a path called orbit.

PLANETS

• Planets are large round object s that move around a star, such as the sun.

• Planets stay in their orbits because of gravity.

• Instead of orbiting in a straight line, gravity causes them to move in an ellipse around the Sun.

• Planets are cooler and smaller than stars.

GRAVITY AND THE MOON• The Moon is the satellite of

Earth.

• A satellite is an object that orbits another object in space.

• All of the planets have at least one moon except for Mercury and Venus.

• Gravity is a force of attraction between objects.

• The Sun and each of its planets are attracted to each other because of gravity.

ORBITING THE SUN

• As the moon is orbiting the Earth, both the Moon and Earth are orbiting the Sun.

• The planet –moon systems stay together as they orbit the sun.

• Gravity between a planet and its moons keeps the moon in orbit.

FREE FALLING

• When you free fall, you are falling in space. Along with your spaceship.

• The spaceship falls all the way around Earth in an orbit.

• Gravity pulls on the ship and astronauts but they do not feel the effect.