private void OnTriggerEnter2D(Collider2D collision)
    {
        FadeShield entity = collision.GetComponentInChildren <FadeShield>();

        if (entity != null)
        {
            entity.updateShieldHealth(gc.asteroidShieldDamage);
            destroyPowerUp();
        }
    }
 // Start is called before the first frame update
 void Start()
 {
     gc     = FindObjectOfType <GameController>();
     shield = FindObjectOfType <FadeShield>();
     shopCanvas.gameObject.SetActive(false);
 }