What is the smallest know planet? And how far away is it from earth?

Question: What is the smallest know planet? And how far away is it from earth?
- Keywords:
  distance,
  earth,
  planet
Asked by aoifeomara to Arlene, Colin, David, Eugene, Paul on 21 Nov 2012.
- Paul Higgins answered on 21 Nov 2012:
  
  Mercury is the smallest planet (pluto is a dwarf planet). The Sun is 90 million miles from earth, and mercury is about 67 million miles from earth (at their closest approach).

Question: What is the smallest know planet? And how far away is it from earth?