All You Need Is A Charge Beam. Run Next To The Gold X Pirate until It Jumps Over You. Charge Up And SHOOT HIS BUTTOX OFF!

missile his back

run up to him 'till he jumps over you and missle his @$$ off

To defeat them, you need to find the Screw Attack!

Hold your Charge Beam, go near in front of the Space Pirate, and then it jumps over you.
And shoots its behind quickly.

Repeat these steps over to unlock those doors. However, you dun need a Screw Attack when
you're in a continuous mission.

aldermar is correct, charge your beam then walk up to it let it jump over you the charge
beams it's behind