@Override
	public int compareTo(Object other) {
		if (other instanceof Vortex) {
			Vortex otherVortex = (Vortex)other;
			if (otherVortex.dayDistance > this.dayDistance) {
				return 1;
			}
			else if (otherVortex.dayDistance < this.dayDistance) {
				return -1;
			}
			else {
				if (otherVortex.dayTravel > this.dayTravel) {
					return 1;
				}
				else if (otherVortex.dayTravel < this.dayTravel) {
					return -1;
				}
				else {
					return 0;
				}
			}
		}
		return -1;
	}