Æthernaut takes place in an alternate past, where classical cosmologies are true.
Space is not a vacuum, but full of æther, and thus traversable by air balloon. Navigating the solar system was made possible by Johannes Kepler's model of the planets and their orbits, based on the five Platonic solids.
Earth is dominated by the vast city-state of New Byzantium; once a small colection of colonies, she rose to power first by trading with the people of Luna (the moon), then by fighting for Earth in a protracted interplanetary war.
This story may be new to you, but it's been dogging me my whole adult life. Some of the core characters date back to high school. They and others appeared in a 230 page graphic novel called The Rogues of Granbreca, my college thesis. The comic was well received by my advisors, who were wonderful, but at the time (1995) I think few of them had much familiarity with the growing sophistication of graphic novels. It took me a few years to realize how poorly drawn and hamfistedly written (like this sentence!) TROG was. I started thinking about a revised version, and a sequel, and if there's a sequel then clearly there should be a trilogy. I started to jot down ideas for new characters and new plot twists, just whenever they occured to me.
After enough years went by I had a folder of Word documents, organized by world, story, and characters. When I decided I actually wanted to re-make the story, I was committed to two other ongoing comics (The Introvert Manifesto and Island of the Moths). I spent another few years finishing those projects, and polishing up my notes on Æthernaut with the intent of making a real story out of it. I believe I've made several vast improvements over the comic I created in college. There could be about 40 copies of TROG still floating around, most given to friends, a handful sold through local comic stores in Eugene. I don't recommend reading it, but for the bloody-minded out there, you can probably still find a copy in the Honors College library at the University of Oregon.