Geocentric

Earth is the center of the solar system and universe, and everything revolves around Earth. 

Heliocentric 

Model showing Earth is not at the center of the universe and Sun is in fact at the center of the solar system; and Earth revolves around the Sun. 

Ptolemy 

developed the model of Earth's movement

Copernicus 

developed the model that Earth revolves around the Sun within the Solar System. 

Planet 

non-stellar mostly spherical object that orbits a star.

Asteroids

rocky/metal objects that generally orbit a star.

Star

self-sustaining object with nuclear fusion core.

Photons

particles made up of energy and upon entering our eyes we perceive them as light. 

Zodiac 

constellations that occupy the celestial equator. 

Sunspots

regions where the sun's magnetic field pokes up in the photosphere.

Refraction 

the process that involves light being bent through an objective lens.

The Doppler Effect

wavelength of light depends on the objects distance to Earth.