My asteroid dont move after shoot - why?

Hello,
I have two scripts - one for my beam and one for asteroid. The problem is, that after my beam shoot asteroid, the asteroid is only move up along Y axis and rotate, but not change z or x position. I thought, that if i attach a rigidbody and cofigurable joint to my asteroid, it will move properly. What I missing?

Beam Script

using UnityEngine;
using System.Collections;

public class Beam : MonoBehaviour {

	public float beamVelocity;
	public GameObject miniExplosion;
	public GameObject go;
	
	
	
	public void Go (Vector3 shipVelocity) 
	{
	
	rigidbody.AddForce(transform.forward + shipVelocity, ForceMode.VelocityChange);
		
	}
	
	void FixedUpdate()
	{		
		rigidbody.AddForce(transform.forward * beamVelocity, ForceMode.Acceleration);
		
	}
	
	void OnTriggerEnter(Collider innyobiekt)
	{
		Asteroid ast = innyobiekt.transform.GetComponent<Asteroid>();
		if(ast != null)
		{
			ast.Hit();
			go = (GameObject)Instantiate(miniExplosion, transform.position, transform.rotation);
			Detonator det = go.GetComponent<Detonator>();
			det.size = 1;
			Destroy(this.gameObject);
			
			
		}
	}
	
}

Asteroid Script

using UnityEngine;
using System.Collections;

public class Asteroid : MonoBehaviour {
	
	
	public float maxAsteroidVelocity;
	public float minAsteroidVelocity;
	public AudioClip explosionSound;
	public GameObject explosionPrefab;
	GameObject go;
	
	private Vector3 velocity;
	private float asteroidHitPoints = 100;

	// Use this for initialization
	void Start () 
	{
	
	}
	
	// Update is called once per frame
	void FixedUpdate () 
	{
		 
	}
	
	public void Hit()
	{
		asteroidHitPoints--;
		if(asteroidHitPoints <= 0)
		{
			Explode();
		}
	}
	
	public void Explode()
	{
		go = (GameObject)Instantiate(explosionPrefab, transform.position, transform.rotation);
		Detonator det = go.GetComponent<Detonator>();
		det.size = 1;
		Destroy(this.gameObject);
	}
	
}

Anyone :)?

From what I can see your beam hits your asteroid and since the beam is moving forward it will push the asteroid with it. What effect are you trying to make happen? The way it looks is the beam fire out of a weapon, hits an asteroid, then is the asteroid suppose to explode?

If you want move asteroid after shoot, use rigidbody !
You have the option drag.