Download Inner planets

Vocabulary
Lesson 1
Solar system: includes all of the planets, moon, and other objects that revolve
around a star.
Planet: a large space object that moves in a curved path around a star
Inner planets: closest to the sun, small and made up of mainly rock and metal
Outer planets: they are further from the sun, large and made up mainly of light
gases and ices
Astronomers: scientists who study the universe
Moon: a natural object that revolves around a planet (are called satellites)
Asteroids: large pieces of space rock with irregular shapes most found in asteroid
belt between mars and Jupiter
Comets: bodies made up of ice, dust and small, gritty particles ice turns to gas,
producing a spectacular streak often called a tail
Meteoroids: pieces of rock or dust that are smaller than asteroids
Meteors: pieces of rock or dust that burn up before they land on Earth also called
shooting stars
Meteorites: are pieces of rock that land on the Earth
Revolution: the movement of a body in space around another body
Orbit: the path that a revolving body takes
Rotation: the movement of a space object turning on its own axis
Axis: an imaginary line that runs through the center of a planet or another body
Lesson 2
Atmosphere: a blanket of gases that surrounds a planet