Space Eggs usually not enough for this level. There are only three space Eggs.
Send the first Space Egg at a low trajectory above the first planetoid so it detonates right by the foot of the structure. This explosion should cause debris to fly around the planetoid hitting the TNT, taking out the all the pigs inhabiting it. Now fire the second space egg below the first planetoid so it does a half figure eight and comes back up and hits the left side of the top structure on the far planetoid.