Match each statement below with the appropriate explanation based on whether it is something that scientists knew about pluto or its moon charon before the new horizons flyby, is something learned as a result of the new horizons flyby, or is something that seems possible from the new horizons mission but for which we'll need additional data to establish it with certainty.

1. pluto is a member of the kuiper belt auto is sometimes nearer to the sun than neptune
2. pluto has a comet-like composition of ice and rock
3. charon has huge, deep canyons
4. pluto's thin atmosphere contains haze particles that can fall to the surface
5. pluto has tall mountains built of water icepluto has smooth plains of nitrogen ice
6. pluto has a subsurface ocean of liquid water
7. pluto has active volcanoes

known prior to new horizons mission, possible but not proven from new horizons mission, pluto is less massive than any of the terrestrial planets, learned from new horizons mission.