Space

Universe All of space that includes many galaxies

Galaxy A system of stars mixed with gas and dust. We are part of the Milky Way Galaxy, which is a spiral galaxy. The next closest galaxy is called Andromeda. There are approximately 200 billion stars in our galaxy.

Solar System The solar system includes the sun and all the bodies that orbit around it.

Planet A spherical body that orbits around the sun and has its own gravity

Put the following in order from largest to smallest: Solar System Universe Galaxy Planet Universe Galaxy Solar System Planet

Inner Planets These are known as terrestrial planets because they are dense and rocky Mercury Venus Earth Mars

Outer Planets These are known as the gas giants because they are very large and mostly made of gas Jupiter Saturn Uranus Neptune

Dwarf Planet - Pluto Pluto is now classified as a dwarf planet because it is very small

Solar System Diagram

Sustain Life Atmosphere: Mixture of gases surrounding earth or a celestial body, held in place by gravity. Sustain: To keep up or keep going.