public void start(Stage StartingStage) throws Exception{

    Group root = new Group();
    Scene scene = new Scene(root);
    Canvas canvas = new Canvas(500, 500);
    root.getChildren().add(canvas);
    StartingStage.setScene(scene);
    StartingStage.show();
    GraphicsContext gc = canvas.getGraphicsContext2D();

    // YOUR STUFF GOES HERE (remove the code below)
    StartingStage.setTitle("Constellations Assignment");
    gc.strokeOval(100, 50, 200, 200);
    gc.fillOval(155, 100, 10, 20);
    gc.fillOval(230, 100, 10, 20);
    gc.strokeArc(150, 160, 100, 50, 180, 180, ArcType.OPEN);

    Image img = new Image("Background.jpg", 100, 0, true, true);
    gc.drawImage(img, 500,500);

}