lesson 1 Flashcards
(31 cards)
What are the North and South Celestial Poles?
The points where Earth’s rotational axis cuts the celestial sphere.
What is the Celestial Equator?
The projection of Earth’s equator in the celestial sphere.
What is the Ecliptic?
The path the sun appears to take around the celestial sphere.
What are Solstices?
The two points on the ecliptic with the greatest distance from the celestial equator.
What is the Summer Solstice?
The point where the sun is at its northernmost position above the celestial equator.
What is the Winter Solstice?
Occurs when the sun is at its southernmost position.
What are Equinoxes?
The two points where the ecliptic intersects the celestial equator.
When does the Autumnal Equinox occur?
September 22.
When does the Vernal or Spring Equinox occur?
March 21.
What is the Terrestrial Domain?
The region below the sphere of the moon.
What is the Celestial Domain?
Everything from the sphere of the moon up.
What is Diurnal Motion?
Earth’s rotation.
What is Annual Motion?
Earth’s revolution.
What is responsible for the seasons?
The tilt of Earth’s axis.
What is the Geocentric Model?
A description of the universe with Earth at the center.
What is the Heliocentric Model?
A description of the universe with the sun at the center.
Did Pythagoras believe in the Geocentric or Heliocentric models?
No, he did not believe in either model.
What was Plato’s view of the universe?
He believed Earth was at the center.
Who placed a spherical Earth at the center of the universe?
Eudoxus of Cnidus.
What is Retrograde Motion?
The apparent motion of a planet in a direction opposite.
What did Nicolaus Copernicus propose?
The Earth spins on its axis and revolves around the sun.
What did Galileo Galilei prove using his telescope?
The sun is the center of the solar system, not the Earth.
What is the Law of Ellipses?
The orbit of each planet about the sun is elliptical.
What is an Orbit?
The path described by one celestial body in its revolution about another.
