Non-Luminary World Classification Scheme

Asteroidal Class

The Asteroidal Class is the most basic, and the most numerous, of all the classes in the NoLWoCS.  There are, of course, even more numerous smaller objects, namely meteoroids and space dust, and these are the ultimate building blocks of any solar system.  But only asteroids can be considered worlds in their own right.  By NoLWoCS definition, these are worlds from 50 meters to 50 kilometers in diameter.  They include the classically separate rocky asteroids and icy comets, mainly because as Man moved out into the Solar System of his birth and investigated these two seemingly disparate bodies, he learned that they often held very similar characteristics.

In a young solar system, gas and dust will come together to form the small meteoroids that, billions of years later, still rain down on all planets.  And these meteoroids will come together and form Asteroidal bodies.  Most of these, in turn, will continue on to create Planetoids, and eventually full fledged planets.  But there are regions where asteroids might survive in their pristine form.  The gravitational interactions between giant planets and central suns can conspire to prevent a planet from coalescing, and thus an asteroid belt will be formed, as was one between the orbits of Mars and Jupiter in the Solar System.  Further out in space, there will remain the almost untouched reserve of frozen cometary bodies in what is called the Oort Belt.  And of course, asteroidal bodies of all types will be nudged into wildly eccentric, often stable orbits that reach throughout a solar system.
The Asteroidal Class - More

Planetoidal Class

There are minor planets in every solar system, bodies that represent the embryos of growing planets in a young solar system, and the still born remains of planets in old systems.  Yet, despite their small size, these worlds are capable of possessing unique characteristics in nearly every facet that the larger, Terrestrial planets have.  Most have barren, cratered surfaces, but many possess surface deposits of ice, and some even have tenuous atmospheres.

By definition, Planetoidal Class bodies range from 51 kilometers to 1,000 kilometers in diameter.  These small worlds also tend to be more spherical in shape, reflecting their larger sizes and greater gravity.

In most cases, Planetoidal bodies initially begin to form in independent orbits, and seem to be well on the way to forming a true planet.  However, various circumstances can arrest this development, and either leave the Planetoid alone in a planetary orbit, or surrounded by other Planetoids and asteroids, as in a belt.  In the Sol System, for example, the Asteroid Belt contains many Planetoids, the largest of which is Ceres.  Quite possibly Ceres, or its large cousin Vesta, are the remnants of a failed planet.  Other Planetoids can form in the furthest reaches of a solar system, and make up the majority of objects to be found in the local Kuiper belt.  Some of these may find their way into the realm of the outer planets and remain as wanderers, or even be captured and become Jovian moons.
The Planetoidal Class - More

Terrestrial Class

By and large, Terrestrial worlds are the end point of planetary growth, typically forming too close to the local sun to accrue the massive amounts of material that exist aplenty beyond the snowline.  However, some Terrestrials, forming in those colder regions, migrate inward due to momentum loss with the protoplanetary disk, and before they can achieve Jovian masses end up in the inner regions, where their growth is halted and a massive planet is formed.  The vast majority of Terrestrial planets, however, are rather small worlds, perhaps averaging four to five thousand kilometers in diameter.  But regardless of their end form, life can often be found upon them.  While it may be restricted to the simplest mono-cellular microbial forms, such worlds nonetheless are the cradles of life, and can be found throughout the Galaxy.

Jovian Class

By and large, Jovian planets exhibit little variation in structure, although their upper atmospheres, visible from space, can vary considerably due to many different factors.  Almost always these worlds are accompanied by large numbers of moons, primarily small rock and ice worlds, although many have at least one large satellite, nearly a planet in its own right.  Through inward migration during the formative years, many Jovians can be found in the inner solar system, some of them even within a close, torch-orbit.  Others orbit far out from the central star, many AU's away, lost in a perpetual frozen night.

Rogue Class

For the most part, these are cold and lifeless worlds, whatever atmospheres that they might have once had long since frozen out onto the surface and as hard as granite.  But some worlds remain heated by their internal fires, forever dark wanderers that glow in the infrared like the last ember of a camp fire.  Other worlds are gas giants, shrunken and quiescent, the tops of their clouds lost in perpetual blizzards, while in their depths the heat of their mass continues unabated, churning the atmosphere below like a boiling cauldron.

It is an irony that these worlds are very common indeed, with an average solar system perhaps losing fifty or more such worlds in the first hundred million years of formation.  Indeed, they form an appreciable amount of the dark mass of the universe.  But they are difficult to find, utterly lost to the blackness and detectable only by the faint gravitational effects on light that the larger massed worlds have.

Artificial Class

While these megastructures are often quite varied in form, they can be broken down into specific Types, based on design lineages and final constructed form.