We live on a unique planet in its precise details, but many of the things about Earth are likely out there in our universe. There are almost certainly other planets that have intelligent, technological life. It would be a huge waste of space otherwise.

Some of those worlds have large satellites. In fact, a large satellite probably helps with the development of intelligent, technological life by stabilizing the long-term climate. Kyx doesn’t have one, and its people have had to learn to deal with it over the centuries.

But it’s possible that, at least in our galaxy, Earth is the only inhabited planet with a satellite that happens to exactly cover the same amount of sky as the primary.