Accessible and intricately researched, with scattered humor to keep the reader's interest.
Getting to space is the easy part. Staying there is going to be a lot more complicated than anyone wants to believe. There are plenty of established tropes in science-fiction and among serious space enthusiasts, but a lot of them have major gaps in them when you start pressing for details. What happens to a fetus in microgravity? Can you scrape together enough soil nutrients to supply agriculture for a whole Mars city, or do you need to constantly import fertilizer from Earth? How do you make sure you have enough medical supplies on-hand?
The authors wanted to write about what we know about space settlement. But it turns out it's a really good primer for what we don't know and need to research before we can get serious.
It's also an interesting companion to Under Alien Skies …