How big is the moon? – Hafnium Zone

Question: How big is the moon?
- Keywords:
  moon,
  size,
  solar system
Asked by RoRo to Susan on 20 Jun 2015.
- Susan Cartwright answered on 20 Jun 2015:
  
  It’s 3474 km in diameter (that’s 0.273 times as big as the Earth) and 73.48 thousand million million million kg in mass (7.348 x 10^22 kg in scientific notation), which is 1/81 times the Earth’s mass.

Question: How big is the moon?