Many years ago.
When Black Hole Lu Chen had just embarked on the journey in the Wandering Universe.
He once casually set a seemingly scientific series of upgrade stages for himself.
These stages were, respectively, meteorite, Star Stone, asteroid, Planet, Constant Star, star system, nebula.
Although it now appears that these stages are not entirely scientifically reasonable, because both star systems and nebulae require the collaborative cooperation of the entire life community, especially since the structure of nebulae is quite extraordinary; if considering evolution from the perspective of a single Celestial Civilization, it might be more sensible for the stages following Constant Star to be White Dwarf Star, neutron star, Quark Star, and Black Hole, with star systems and nebulae belonging to the upgrade path and stages of life communities.
Nevertheless, this precisely proves that knowledge always evolves with scientific progress, and is not immutable.
