it gives me an error 'transform' is not member of Object. How do I tell unity that the objects I put in the array , are GameObjects.

#pragma strict


var MaxPlanets:int = 10;
var clonePlanet : GameObject;
var PlanetMaterial : Material;
var planetGroundMaps : Texture[];
var planets:Array = new Array();

function Start () {
createPlanets();
}

function Update () {
rotatePlanets();
}


function createPlanets():void{
var radiusMax:float = 5;
var radiusMin:float = 1;
var radiusRan:float;
var Angle:float;
var planetPosition:Vector3 = new Vector3(0,0,0);
var planetRotation:float;
var RanTexture:int;


    for(var i:int = 0;i <= MaxPlanets;i++){
       radiusRan = Random.Range(radiusMin,radiusMax);;
       Angle = ((360 / MaxPlanets) * i) * (Mathf.PI/180);
       planetPosition.x = Mathf.Cos(Angle) * radiusRan;
       planetPosition.z = Mathf.Sin(Angle) * radiusRan;
       var newPlanet = Instantiate(clonePlanet,planetPosition,Quaternion.identity);
       RanTexture = Random.Range(0,4);
       newPlanet.renderer.material = PlanetMaterial;
       newPlanet.renderer.material.SetTexture("_PlanetGround",planetGroundMaps[RanTexture]);
        if(RanTexture<3){
        newPlanet.renderer.material.SetTexture("_Clouds",null);
        newPlanet.renderer.material.SetTexture("_HeightMap",null);
        newPlanet.renderer.material.SetTexture("_lights",null);
       planets.Add(newPlanet.gameObject );
        }
    }
}

function rotatePlanets():void{
    for (var i in planets){
       i.transform.RotateAround(Vector3.zero,Vector3.up,Time.deltaTime);
    }
}