Midterm Flashcards
What does heliocentric mean?
The model where earth spins on its axis and orbits the sun like all other planets
Who discovered the heliocentric model and when?
Nicholas Copernicus rediscovered it in the 16th century
How does the heliocentric model explain the seasons and retrogrades ?
Retrograde is when earth overtakes a planet such as mars and it appears to go backwards like cars passing on a freeway
Geocentric
Earth is the center of the universe and all other bodies move around it
Epicycles
The epicycle is the small circle planets supposedly moved in while still going in a large circle around earth
Deferent
The large circle the planets orbit around earth
Prograde
The normal forward orbit of planets
Retrograde
When planets appear to go backwards (westward) int he sky because earth is passing them
Waxing
When the moon or another celestial body appears to be gaining light becoming more illuminated each day
Waning
As the moon approaches a new moon it is less illuminated in the view of earth each day
