Like say Sik, homing aim is not the good weapon for hit the core. If you want help see bellow :
Each turret protect the core, destroy only one and you can hit the core but the angle to hit is small.
If you destroy 2 ajacent turret the "protection wall" beetween them is destroy too and hit the core is easy.
https://youtu.be/FYFq5mrdDLI?t=1690

