TERRIS is so distant from its sun that its surface is almost entirely snow and ice.  Its hardy inhabitants are firm believers in democracy, but their politics are of a very agressive sort.  Every citizen has one vote, which must be cast according to the will of the last person to defeat that citizen in a government-scheduled martial arts tournament.  There is therefore a great deal of societal emphasis on learning how to fight.  Hardly anyone will publicly admit to having an interest in any science not directly related to their combative skills.  In secret, however, many people of Terris learn other ways to improve their world, and they teach these subjects to others in private.  It is considered impolite to wonder who provides the hydroponic gardens and fusion reactors necessary to support life on Terris.

FILÉ is an ocean planet, completely covered by water.  The gill-breathing Filéans constantly follow its currents in peace.  They are ostensibly ruled by a hereditary king, whose laws are absolutely obeyed by everyone on the entire planet.  The only laws which are seen as fit for the king to proclaim, however, are the laws of mathematics.  So no one may claim that 2 + 2 = 5, for example, but other than that everyone is free to do as they wish.  Mathemeticians on Filé keep busy in proving new laws for the king to enforce, but their society is otherwise decadent.  They have never heard of Kurt Friedrich Gödel.

FREMANTLE is inhabited by a collective society of humans called the Noongar, and also by a species of living cloud-creatures (Woylie) that have great influence on the meteorological properties of the planet.  The Noongar used artificially-intelligent satellites to communicate with the Woylie, which have very limited sentience but can be trained to affect the atmosphere in many ways.  Initially this led to great prosperity on Fremantle, with rains falling just where they were needed most.  But cosmic radiation eventually caused bit-rot in the software running on the satellites, and their programming went completely haywire.  Rains became torrential, leading to massive flooding.  Lightning and powerful cyclones also became extremely prevalent.  All of the large structures on Fremantle have now been destroyed, forcing the Noongar to collectively shelter in the ruins.