Issues with Prototype Interactive Space Map

Question

I'm building an interactive website for a space RPG for a group of my friends. It's supposed to show a group Map that shows quests/planets to logged in users. At the moment I'm doing preliminary work on the map and have run into a problem with Createjs, specifically the bitmap.

I've ran through trying to add the image into the background in multiple ways and nothing seems to work. Either the galaxy image would not render in or it would be appended to the bottom of the canvas.

The function galaxyMap() is the one I'm currently working on.

Almost Full Code Snippet

It's rather plain and lacking any proper CSS but that isn't important, as I'm wanting to build at least a workable proof first. For visual reference on the idea of what the finished product would look like; imagine a more simple spiral galaxy map from the game Spore

Edit: I've added a shortened plain text snippet of the js code to help.

var stage;
//variable dimensions, related to canvas size
var dimensionX = 1365;
var dimensionY = 1365;

function init() {
    stage = new createjs.Stage("demoCanvas");
    galaxyMap();
    stage.update();
}

function galaxyMap() {
    var bitmap = new createjs.Bitmap("img/galaxy.jpg");
    stage.addChild(bitmap);
}