How to affect only one object out of many objects with the same name using script?

I created many instances of planet object using a prefab and I only want to affect a single instance of the planet. I deleted some code here but if I click on a planet, it should show the status of the single planet that I clicked on but status of all instances of planet shows up.

I have tried putting this. and using GetChildComponents but none of these seem to work including the .Find I'm using. Please help!

public class PlanetStatus : MonoBehaviour { private Canvas statusCanvas; private string tagName;

 // Use this for initialization
 void Start () {
     statusCanvas = transform.Find ("Canvas").gameObject.GetComponent<Canvas> ();
     tagName = "";
 }

    ...........

 void showCanvas (string tagName) {
     if (tagName == "Planet") {
         if (statusCanvas.enabled) {
             statusCanvas.enabled = false;
         } else {
             statusCanvas.enabled = true;
         }
     }
 }

}