How can I make the nearest astroid move to my preset location?

In the code I have it finding the nearest object with the "Astroid" tag and when I hit the Fire3 key, it SHOULD move to the location transform which is directly in front of my player as a child object. But when ever I hit the 'C' key (Fire3), it just makes the nearest astroid disappear! So I'm pretty sure it's finding the closest astroid, but I still need to make it lock to the location transform position. Here's the code: using UnityEngine; using System.Collections;

 public class AstroidFind : MonoBehaviour {
 
     private GameObject[] gos;
     private float distance;
     private GameObject closest;
     public Transform location;
     public float speed;
 
     void Update() {
 
         float step = speed * Time.deltaTime;
         gos = GameObject.FindGameObjectsWithTag ("Astroid");
         distance = Mathf.Infinity;
 
         foreach (GameObject go in gos) 
         {
             Vector3 diff = go.transform.position - transform.position;
             float curDistance = diff.sqrMagnitude;
 
             if (curDistance < distance)
             {
                 closest = go;
                 distance = curDistance;
                 print ("Found Closest Astroid!");
             }
         }
 
         if (Input.GetButtonDown ("Fire3")) 
         {
             closest.transform.position = Vector3.MoveTowards (transform.position, location.position, step);
         }
     }
 }

If anyone can help me it would be greatly appreciated!