         <th colspan="2"></th>
                                        <th scope="col">Name</th>
                                        <th scope="col">Mass (10<sup>24</sup>kg)</th>
                                        <th scope="col">Diameter (km)</th>
                                        <th scope="col">Density (kg/m<sup>3</sup>)</th>
                                        <th scope="col">Gravity (m/s<sup>2</sup>)</th>
                                        <th scope="col">Length of day (hours)</