Unit 1 Review

The ____ Sphere is a model of stars & constellations.

• Neon

• Solar

• Celestial

• Universal

The apparent "backward" (westward motion) of the planets Mars, Jupiter, or Saturn in the sky relative to the stars is known as ____ motion.

• backward

• ecliptic

• forward

• retrograde

Central to the heliocentric model is the assertion that the observed motions of the planets and the Sun are the result of ____ motion around the Sun.

• retrograde

• Mars'

• elliptical

• Earth's

Newton's first law of inertia states that a moving object will continue to move in a straight line with constant speed unless acted upon by a ____.

• moon

• star

• planet

• force

Rotation is the term used to describe the motion of a body around some ____.

• axis

• planet

• point

• star

The apparent path of the Sun across the sky is known as the ____.

• ecliptic

• equator

• zodiac

• celestial sphere

According to the diagram, when it's winter in the Northern hemisphere it is ___ in the Southern hemisphere.

• winter

• fall

• summer

• spring

Dec. 21st and June 21st are collectively known as the ___ .

• solstices

• seasons

• equinoxes

• tilt

March 21st and Sept. 21st are collectively known as the ___ .

• solstices

• seasons

• equinoxes

• tilt

The Earth is tilted at ___ degrees causing seasons to occur in the mid-latitudes.

• 0

• 50

• 23.5

• 11.5