I have noticed that larger star systems do not always display all the planets of the system. Clicking on a star gives a summary of the planets, but as in the image
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the two systems Sander and Skowbo both have 5 planets but neither shows 5 planets - Skowbo shows 4 and Sander only 3. In the case of Sander, 1 of the unshown planets is a Habitable one...