Quiz 8

1. How many moons does Mercury have?
a. None.
b. One.
c. Two.
d. Four.

2. What caused the long cliffs or scarps seen on Mercury's surface?
a. An impact from a large asteroid.
b. The gravitational pull from the Sun.
c. The cooling and shrinking of the planet's interior.
d. Erosion by Mercury's thick atmosphere.

3. What is unusual about the rotation of Venus?
a. It is the fastest rotating planet.
b. It rotates in a retrograde direction.
c. Venus does not rotate at all.
d. The rotation rate is increasing over time.

4. Why don't we learn anything about the surface of Venus from ordinary photographs, even using a telescope?
a. Because we are much too far to see any details.
b. Because the surface is made of perfectly smooth rock, without any features.
c. Because Venus is always completely covered by thick clouds.
d. Because there is always too much sunlight in the sky when Venus is up.

5. How fast does the Moon rotate?