Universe and Solar System

Front

Universe

Back

everything that exists, including space, time, matter, energy

Front

Big Bang Theory

Back

universe created by a giant explosion

Front

Galaxy

Back

system of billions of stars, gas, dust

Front

Solar System

Back

star and celestial bodies orbiting it

Front

Heliocentric Model

Back

sun at the center of the solar system

Front

Geocentric Model

Back

Earth at the center of the solar system

Front

Planets

Back

celestial body in elliptical orbit around a star

Front

Ellipse

Back

elongated circle; oval

Front

Nicolaus Copernicus

Back

first model placing Sun at center

Front

Galileo Galilei

Back

astronomer, improved telescope, confirmed heliocentric model