Why do space rockets not drift away ( or find it hard to move) when they’re on a planet with low gravity(e.g Neptune)

Question: Why do space rockets not drift away ( or find it hard to move) when they're on a planet with low gravity(e.g Neptune) and we do?
- Keywords:
  gravity,
  neptune,
  rocket,
  space
Asked by maddiec to Christina, Jess on 28 Jun 2013.
- Christina Pagel answered on 28 Jun 2013:
  
  Neptune’s gravity is actually very similar to ours!
  
  In a vacuum (outer space) there’s no friction, and so once you’re moving in a direction you just keep going unless you change direction by using a jet.
  
  space rockets can orbit around planets (even low gravity planets or moons) because the gravity acts constantly – so the space rocket is like a ball on string being swung around – because you in a vacuum, the rocket will just keep going like this forever.
  
  In fact, close to a planet it’s not a perfect vacuum and eventually the rocket will slow down and get closer to the planet until it crashes (this can happen to satellites orbiting the earth)

Question: Why do space rockets not drift away ( or find it hard to move) when they're on a planet with low gravity(e.g Neptune) and we do?