From the publisher blurb:
Beyond the oasis of light and warmth made by stars lie the vast, freezing, voids of interstellar space. Through these wander the rogue planets: Worlds spat into the dark during their solar system's early youth, and worlds that formed without any warming star to begin with. But, despite billions of years in the interstellar night, many of them are not entirely dead - some could support entire civilisations in the darkness. Nor are they exactly rare...
Using a series of simple, flexible look-up tables, this book sets out a range of possible, scientifically plausible, rogue planets - including moon systems for rogue gas giants, radiation, likely environments, hazards, opportunities and visuals. Putting storytelling ahead of technical detail, but with plenty of in-depth material for those wanting to do a deeper dive, this third installment in the Hard SF Worldbuilding Cookbooks series covers:
Locations in interstellar space - Page 8
Rogue planet tropes - page 17
Trope modifiers - page 29
Rogue gas giant planets and their moon systems - page 31
Tropes for moons of rogue gas giants - page 39
Glossary - page 55
Equations used - page 61
Further reading - page 63