Quantum Mechanix produces sci-fi memorabilia, including a lot of Firefly stuff. I'm not affiliated with this company in fact I don't even own any of their stuff. Having said that, I do follow their blog and was very interested to see their Map of the Firefly/Serenity universe. It's pretty elaborate and they also went to the trouble of creating this guide (PDF file) to the history of the Fireflyverse as a companion.
It makes for some pretty interesting reading. They postulate the Firefly system is a small star cluster of five stars and seven brown dwarfs. They also introduce the concept of "helioforming," by which brown dwarfs and very large gas giant planets are compressed and ignited to form artificial stars. It also talks about the terraforming process for the planets on this show suggesting that it would be necessary to compress planets and moons to make them dense enough to raise their gravity to that of Earth's and give them a second rotational axis to simulate the change of season that comes with Earth's 365 day revolution around the sun. It has some pretty interesting and attractive ideas to me and makes for interesting reading for fans of the show.
Titan: Moon over Saturn - [image: Like Earth's moon,] Like Earth's moon,
5 hours ago