private Vector3D getAccelerationForCraft(Craft craft) {
		// Uses mass of all bodies
		Vector3D aTotal = new Vector3D();
		for (int i = 0; i < bodies.size(); i++) {
			Body body = bodies.get(i);

			if (body.mass == 0) {
				break;
			}

			Vector3D diff = body.position.clone().subtract(craft.position);
			double mag = diff.magnitude();
			Vector3D a = diff.multiply(body.mass / Math.pow(mag, 3));
			aTotal.add(a);
		}
		return aTotal.multiply(Astrophysics.G);
	}