Not the order from the Sun
The sequence
Eight worlds, a proposed start at Jupiter’s Great Red Spot, and two remnants. Look at each body first. Then as a stage.
- 1. Proposed beginningGreat Red SpotJupiter’s longest-lived large storm. If a new world is starting, it would sit under this weather, not in the clouds we can see.
- 2. Stage 1IoThe most volcanic silicate world known. Almost no craters. Sulfur still paints the ground. The first visible rocky face in the sequence.
- 3. Stage 2EuropaA global ocean under ice that is geologically young. Dry Io to this much water is the first hard riddle of the sequence.
- 4. Stage 3GanymedeThe largest moon in the solar system — bigger than Mercury. Layered inside. The only moon with a magnetic field of its own. Dark old land and younger grooved land.
- 5. Stage 4CallistoThe outer Galilean world. Thick ice. A surface that has been largely still. The most cratered of Jupiter’s large moons.
- 6. Stage 5TitanNitrogen air. Methane rain. Lakes and seas. The first thick atmosphere in the sequence.
- 7. Stage 6TritonNeptune’s large moon. It orbits the wrong way. Capture is granted. The leftover question is the body itself, not the frost on top.
- 8. Stage 7MarsA day like ours. A tilt like ours. Land of continental scale. Air that was once thicker. The last stop before a living Earth.
- 9. Stage 8EarthOceans, breathable air, a biosphere. The only world we know that completed the sequence into a living planet.
- 10. Prior remnantVenusEarth-sized and spent. Ninety-two bars of carbon dioxide. A surface wiped a few hundred million years ago. Read as an ending, not a first draft.
- 11. Prior remnantMercuryMost of the planet is core. It has shrunk. Ice hides in polar dark. The last ash of a finished world, or a stripped first-generation body.