Fry Me To the Moon 3-7 (Angry Birds Space)

Strategy
For Fry Me To the Moon 3-7, fire the first Blue bird into the orbiting asteroid along the south side. This is a difficult timing-shot, but you want to actually hit the asteroid so it falls straight into the planet, as opposed to slowly descending. This should open up a path to use a Lazer bird or two to take out the iron boxes enclosing the planet.