public void run() {
        //Create Map
        map = new HashMap<Double, Planet>();
        for (Planet p : oldPlanets) {
            map.put(p.getId(), p);
        }

        for (Planet p : currentPlanets) {
            if (map.get(p.getId()) == null) {
                continue;
            }
            if (!(map.get(p.getId()).getCoords().equals(p.getCoords()))) {
                moved.add(p);
            }
        }
    }