Project: Space Shooter "Array index is out of range" (Post Tutorial)

I have completed Space Shooter the tutorial and am now adding the additional two asteroids and alien spacecraft. I get the following error in my console.

Error Message:

IndexOutOfRangeException: Array index is out of range.
GameController+c__Iterator0.MoveNext () (at Assets/Scripts/GameController.cs:47)

When play is selected I see the background. It scrolls. The ship can be controlled and fire shots. Music plays. No asteroids descend.

I am not sure if this is a scripting issue or something else. GameController script below.

GameController Script:

using UnityEngine;
using System.Collections;
using UnityEngine.UI;

public class GameController : MonoBehaviour
{
		public GameObject[] hazards;
		public Vector3 spawnValues;
		public int hazardCount;
		public float spawnWait;
		public float startWait;
		public float waveWait;
	
		public Text scoreText;
		public Text restartText;
		public Text gameOverText;
	
		private bool gameOver;
		private bool restart;
		private int score;
	
		void Start ()
		{
				gameOver = false;
				restart = false;
				restartText.text = "";
				gameOverText.text = "";
				score = 0;
				UpdateScore ();
				StartCoroutine (SpawnWaves ());
		}
	
		void Update ()
		{
				if (restart) {
						if (Input.GetKeyDown (KeyCode.R)) {
								Application.LoadLevel (Application.loadedLevel);
						}
				}
		}
	
		IEnumerator SpawnWaves ()
		{
				yield return new WaitForSeconds (startWait);
				while (true) {
						for (int i = 0; i < hazardCount; i++) {
								GameObject hazard = hazards [Random.Range (0, hazards.Length)];
								Vector3 spawnPosition = new Vector3 (Random.Range (-spawnValues.x, spawnValues.x), spawnValues.y, spawnValues.z);
								Quaternion spawnRotation = Quaternion.identity;
								Instantiate (hazard, spawnPosition, spawnRotation);
								yield return new WaitForSeconds (spawnWait);
						}
						yield return new WaitForSeconds (waveWait);
			
						if (gameOver) {
								restartText.text = "Press 'R' for Restart";
								restart = true;
								break;
						}
				}
		}
	
		public void AddScore (int newScoreValue)
		{
				score += newScoreValue;
				UpdateScore ();
		}
	
		void UpdateScore ()
		{
				scoreText.text = "Score: " + score;
		}
	
		public void GameOver ()
		{
				gameOverText.text = "Game Over!";
				gameOver = true;
		}
}

Attached is a photo of the inspector.

I have tried changing the numbers in the public fields without success.

Any guidance in identifying the solution would be appreciated.

[38586-screen+shot+2015-01-10+at+12.58.41+pm.png|38586]

Thanks - that comment alerted me to the Hazards “triangle” that I had not noticed. I added the number 3, and selected the asteroids and the one asteroid I have as a prefab is working. I can now make the other two pre-fabs and get them working from here.