How do I spawn allies properly?

I'm trying to spawn spaceship soldiers in this game I'm working in, I've created some scripts to test if I was correct but then I noticed that the first spawned spaceship always receive a null target and all the others behave correctly.

The scripts:

SpaceshipController.cs:

 public class SpaceshipController : MonoBehaviour
 {
 
     public float spaceshipValue;
     public Transform target;
     private NavMeshAgent spaceship;
 
     private const float SPEED = 3;
 
     // Use this for initialization
     void Start()
     {
         spaceship = GetComponent<NavMeshAgent>();
     }
 
     // Update is called once per frame
     void FixedUpdate()
     {
         if (target != null)
         {
             Follow();
         }        
     }
 
     void Follow()
     {
         transform.Rotate(-90, transform.localRotation.y, transform.localRotation.z);
         spaceship.SetDestination(target.position);
 
     }
 
     public void SetTarget(Transform target)
     {
         this.target = target;
     }
 
     public void SetValue(float value)
     {
         spaceshipValue = value;
     }
 
     public float GetValue()
     {
         return spaceshipValue;
     }
 
     void OnCollisionEnter(Collision collision)
     {
         if (collision.gameObject.tag == "Planet")
         {
             Physics.IgnoreCollision(collision.gameObject.GetComponent<Collider>(), GetComponent<Collider>());
         }
     }
 }

Planet.cs:

 public class Planet : MonoBehaviour {

 [SerializeField]
 private float      speed;
 public  GameObject spaceship;

 // Use this for initialization
 void Start () {
 
 }
 
 // Update is called once per frame
 void Update () {
     transform.Rotate(Vector3.up, speed * Time.deltaTime);
 }

 public void LaunchSpaceship(Transform target)
 {
     Instantiate(spaceship);
     spaceship.GetComponent<SpaceshipController>().SetTarget(target);
     spaceship.GetComponent<SpaceshipController>().SetValue(10);
 }
 }

GameManager.cs:

 public class GameManager : MonoBehaviour {
 
     [SerializeField] private GameObject planet1;
     [SerializeField] private GameObject planet2;
 
     // Use this for initialization
     void Start () {
     
     }
 
     // Update is called once per frame
     void Update() {
         if (Input.GetKeyDown(KeyCode.Space))
         {
             planet1.GetComponent<Planet>().LaunchSpaceship(planet2.transform);
         }
     }
 }
 

Do you guys have any ideas why the first spawned spaceship always behave wrong?

P.S: English is not my mother language, so sorry for any mistakes.