1. Which part of a comet is solid? a. nucleus, b. halo, c. gas tail, d. dust tail, e. coma 2. Suppose you were standing on Pluto. Describe the motions of Charon relative to the horizon. Under what...

1. Which part of a comet is solid? a. nucleus, b. halo, c. gas tail, d. dust tail, e. coma

2. Suppose you were standing on Pluto. Describe the motions of Charon relative to the horizon. Under what circumstances would you never see Charon?

3. Describe the circumstantial evidence that supports the idea that Pluto is one of a thousand similar icy worlds that once occupied the outer regions of the solar system.