1. What did the Voyager mission discover about the main rings of Saturn?

a. There are several moons inside the inner-most ring.
b. The ring system is much thicker than originally believed.
c. They were less dense than the rings of Jupiter.
d. They are composed of tens of thousands of narrow ringlets.
e. There are hundreds of small moons in the ring system.

2. Titan is an interesting moon because:

a. it is known to have ice volcanism on its surface.
b. it has a rich atmosphere that may resemble that of the early Earth.
c. the Huygens rover has sent back images of sedimentary rocks there.
d. beneath its clouds, Titan may be Earth-like, with liquid water.
e. all of the above.

3. The outer jovian planets have a bluish tint because:

a. they are far away and distance makes objects appear bluish.
b. ammonia ice reflects blue light better than any other color.
c. their atmospheres contain hydrogen and helium.
d. at their distances, the Sun appears blue, the red absorbed by dust in the ecliptic.
e. their atmospheres contain methane, which absorbs red light.

4. Pluto cannot be called a jovian planet because:

a. it is more like a terrestrial planet in terms of its density.
b. in size and mass, it is more like on eof their icy moons.
c. it has no rings.
d. its orbit is not as circular as are the jovians.
e. it has more helium than hydrogen in its thin atmosphere.

5. The planets with retrograde rotations are:

a. Venus and Uranus
b. Venus, Uranus and Pluto
c. Venus and Jupiter
d. Venus and Triton
e. Mercury, Venus and Uranus

6. Th Appolo and Aten asteroids have orbits that:

a. remain between Mars and Jupiter, in the main belt.
b. stay sixty degrees ahead of or behind Jupiter.
c. cross the orbit of Mars, but not the Earth, at perihelion.
d. stay out beyond Neptune.
e. cross the orbit of Earth at perihelion.