Earths Role in the Universe

1. Who was the ancient Greek that developed a geocentric model of the universe explaining the observable motions of the planets?

• Aristotle

• Ptolemy

• Copernicus

• Kepler

• Ptolemy

One astronomical unit averages about ____.

• 93 million miles

• 210 million kilometers

• 39 million miles

• 93 million km

Ancient astronomers believed that ____.

• Earth revolved around the celestial sphere

• the Sun was the center of the universe

• the Sun was on the celestial sphere

• Earth was the center of the universe

The apparent westward movement of a planet against the background of stars is called ____.

• retrograde motion

• reverse motion

• westward drift

• Ptolemaic motion

Which one of the following planets was unknown to the ancient Greeks?

• Earth

• Mars

• Uranus

• mercury

Using Tycho Brahe’s data, which scientist proposed three laws of planetary motion?

• Newton

• Galileo

• Kepler

• Copernicus

The first modern astronomer to propose a Sun-centered solar system was ____.

• Galileo

• Newton

• Ptolemy

• Copernicus

Which scientist discovered that Venus has phases, just like the Moon?

• Galileo

• Ptolemy

• Kepler

• Copernicus

The shape of a planet’s orbit is ____

• circular

• irregular

• constantly changing

• elliptical