Trigger Methods are not activating.

I am trying to use a the default onTrigger methods, but they don’t seem to be activating. I’ve 2 basic game objects, each with a script attached.The asteroid is what I want to act as a trigger, but I don’t the console output that I expect from the code.

using UnityEngine;
using System.Collections;

public class AsteriodController : MonoBehaviour {

	// Use this for initialization
	void Start () {
	
	}
	
	// Update is called once per frame
	void Update () {
	
	}

	void onTriggerEnter(Collider other){
		
		Debug.Log(gameObject.name + "Object entered the trigger");
		
	}

	void onTriggerStay(Collider other){
		
		Debug.Log(gameObject.name + "Object is within the trigger");
		
	}

	void onTriggerExit(Collider other){
		
		Debug.Log(gameObject.name + "Object exited the trigger");
		
	}

}

Here is a picture of my asteroid with collider, which I want to call the trigger method:

And here is the player UFO, which I want to activate the trigger:

Check “IsTrigger” in your UFO SphereCollider component.