Golden Eggsteroid 1 is located on Level 1-9 of Angry Birds Space. Zoom out and you'll see the Golden Eggsteroid hidden in the brush below the two bubbled-pigs. Fire any of the Blue Birds to reach it. Once you hit the egg, you'll immediately be transported via a wormhole to the level.
Aliens can be annoying for some.
Fire the Bomb Bird at the second to hit the last glass piece on the right so Bomb destroys it and also knocks the stone piece above. This action should knock the wood UFO and pop the pig.