Hello Chris Mills!
I finally finished the table assessment, but when I put it through the w3c validator, it gives me
"Error, A table row was 1 columns wide, which is less than the column count established using column markup (12)."
also I tried putting the mdn one on w3c validator but same result (but more errors because the tag did not span to 12 in the col markup? thats what I did.)
please help!
<!Doctype Html>
<html>
<Head>
<meta charset="utf-8">
<meta name="description" content="Data table for planets">
<title>Plant data table</title>
<link rel="stylesheet" href="table.css" type="text/css">
</Head>
<body>
<h1>Planet Data Table</h1>
<table>
<caption> Data about the planets of our solar
system(Planetary facts taken from
<a href="http://nssdc.gsfc.nasa.gov/planetary/factsheet/"> Nasa's
Planetary Fact Sheet - Metric.</a>)
</caption>
<colgroup>
<col span="2">
<col style="border:2px solid black">
<col span="9">
</colgroup>
<thead>
<tr>
<th colspan="2"> </th>
<th>Name</th>
<th>Mass<br> (10<sup>24</sup>kg)</th>
<th>Diameter <br> (km)</th>
<th>Density <br> (kg/m<sup>3</sup>)</th>
<th>Gravity <br> (m/s<sup>2</sup>)</th>
<th>Length<br> of day<br>(hours)</th>
<th>Distance <br> from <br> Sun <br> (10<sup>6</sup>km)</th>
<th>Mean <br> temperature <br> (<sup>○</sup>C)</th>
<th>Number of moons </th>
<th>Notes</th>
</tr>
</thead>
<tbody>
<!--Terrestial planets + Mercury-->
<tr>
<th colspan="2" rowspan="4"> Terrestial planets</th>
<th>Mercury</th>
<td>0.330</td>
<td>4,879</td>
<td>5427</td>
<td>3.7</td>
<td>4222.6</td>
<td>57.9</td>
<td>167</td>
<td>0</td>
<td>Closest to the Sun</td>
</tr>
<!--Venus-->
<tr>
<th>Venus </th>
<td>4.87</td>
<td>12,104</td>
<td>5243</td>
<td>8.9</td>
<td>2802.0</td>
<td>108.2</td>
<td>464</td>
<td>0</td>
<td> </td>
</tr>
<!--Earth-->
<tr>
<th> Earth</th>
<td>5.97</td>
<td>12,756</td>
<td>5514</td>
<td>9.8</td>
<td>24.0</td>
<td>149.6 </td>
<td>15</td>
<td>1</td>
<td>Our world</td>
</tr>
<!--Mars-->
<tr>
<th>Mars</th>
<td>0.642</td>
<td>6,792</td>
<td>3933</td>
<td>3.7</td>
<td>24.7</td>
<td>227.9</td>
<td>-65</td>
<td>2</td>
<td>The red planet</td>
</tr>
<!--Jovian Planets-->
<tr>
<th rowspan="5" colspan="1">Jovian planets</th>
</tr>
<!--Gas giants + Jupiter-->
<tr>
<th rowspan="2"> Gas giants </th>
<th>Jupiter</th>
<td>1898</td>
<td>142,984</td>
<td>1326</td>
<td>23.1</td>
<td>9.9</td>
<td>778.6</td>
<td>-110</td>
<td>67</td>
<td>The largest planet</td>
</tr>
<!--saturn-->
<tr>
<th>Saturn </th>
<td>568</td>
<td>120,536</td>
<td>687</td>
<td>9.0</td>
<td>10.7</td>
<td>1433.5</td>
<td>-140</td>
<td>62</td>
<td> </td>
</tr>
<!--Ice giant + Uranus-->
<tr>
<th rowspan="2">Ice giants</th>
<th>Uranus</th>
<td>86.8</td>
<td>51,118</td>
<td>1271</td>
<td>8.7</td>
<td>17.2</td>
<td>2872.5</td>
<td>-195</td>
<td>27</td>
<td> </td>
</tr>
<tr>
<th>Neptune</th>
<td>102</td>
<td>49,528</td>
<td>1638</td>
<td>11.0</td>
<td>16.1</td>
<td>4495.1</td>
<td>-200</td>
<td>14</td>
<td> </td>
</tr>
</tbody>
<!--Dwarft planets + Pluto-->
<tfoot>
<tr>
<th colspan="2"> Dwarf planets </th>
<th> Pluto </th>
<td>0.0146</td>
<td>2,370</td>
<td>2095</td>
<td>0.7</td>
<td>153.3</td>
<td>5906.4</td>
<td>-225</td>
<td>5</td>
<td>Declassified as a planet in 2006,
but this <a href="http://www.usatoday.com/story/tech/2014/10/02/pluto-planet-solar-system/16578959/">remains controversial</a>
</td>
</tr>
</tfoot>
</table>
</body>
</html>
Thanks Chris!