There's a great concept that I found out about reading Schlock Mercenary (a sci-fi webcomic), about using a gas giant as an interstellar spaceship [1]. It proba

There's a great concept that I found out about reading Schlock Mercenary (a sci-fi webcomic), about using a gas giant as an interstellar spaceship [1]. It probably originates elsewhere, but it was nicely explained there. You build a "candle" (huge tube) that is inserted into the gas giant on one side, then ignite the gases inside it (iirc the comic uses fusion reactors on both ends, and an intake in the center of the candle). Both ends of the candle are open, "inner" end counteracts the gas giant's gravity to keep the candle from sinking into the core, the other end produces thrust. You put your payload on moons that orbit around the gas giant, and steer by moving the candle. The "thrust end" of the candle also doubles as a light and heat source for the moons, replacing the sun while in interstellar space. There are... some risks involved into the whole operation. [1]: https://www.schlockmercenary.com/2003-08-03 https://www.schlockmercenary.com/2003-08-03