@Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;
        if (hashCode() == o.hashCode()) return true;//todo COLLISION?
        ArtificialSatellite that = (ArtificialSatellite) o;

        if (electricCharge != that.electricCharge) return false;
        if (energySource != that.energySource) return false;

        return true;
    }