Pluto

1. The best argument against the hypothesis of Pluto having been ejected from Neptune is

a. the presence of Pluto's satellite*

b. the orbital properties of Neptune's current satellites

c. conservation of angular momentum

d. Kepler's third law

e. Newton's third law

2. About what fraction of its orbit has Pluto traversed since it was discovered?

a. 20%*

b. 40%

c. 60%

d. 80%

e. None of these.

3. What evidence suggests that Pluto is not a "normal" planet?

a. The eccentricity and inclination of the orbit.

b. Its small size, coupled with its location beyond the giants.

c. Its extremely low density.

d. All of these.*

e. None of these.

4. In what way(s) does Pluto resemble the Galilean moons of Jupiter?

a. size

b. density

c. mass

d. all of the above*

e. none of the above

5. Which of the following molecules is found in the spectrum of Uranus, Neptune, and Pluto?

a. methane*

b. carbon dioxide

c. water vapor

d. nitrogen

e. ozone