Asteroidal Class
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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.
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Vulcanian Type One of the several dynamically stable orbital zones in most solar systems is that which lies quite close to the parent sun. These epistellar regions often contain a planet of some form, but those that do not almost always have a population of a few hundred asteroidal bodies five kilometers or less in diameter. These bodies are largely unchanged since the formation of the solar system, but because of the intense thermal conditions present they tend to be dense and metallic in nature, and many possess quite unique mineral assemblages not seen on other solar system bodies. As a consequence of their placement, Vulcanians do not present an impact hazard to Gaian worlds, although they do threaten Vesperian Type planets. Indeed, only the inner planets are threatened by these vast rocks, and that typically ranges out to approximately 3.5 AU. In many systems, however, this population may have long since been gravitationally scattered by still forming planets that migrated inward and eventually were consumed by the sun. Vulcanians are considered to be among the greatest prizes as far as asteroids are concerned, due to their immense mineralogical wealth. They can also be among the most difficult to procure and to move to a processing site because of thermal stressing, and the energy requirements to move such a body out of the local sun's gravity well. |
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Metallic Type Sideritic asteroids are composed of almost pure nickel iron, and represent a sizeable proportion of all asteroids in most star systems. They are moderately bright and fairly dense. It is believed that these asteroids originated from larger parent bodies that had developed sufficiently to become differentiated; that is, they had begun to form a crust, mantle, and core. Almost certainly these bodies were then destroyed by collisional processes with other bodies in the very early stages of planetary formation, when a typical inner system region might contain hundreds of planetesimal bodies. The result would be, of course, the smaller and often irregularly shaped metallic Sideritic asteroids. Many Siderites have eccentric orbits, reflecting the volatile birth that they experienced. However, many are also found in confined belt orbits. Those in belt orbits are prone to further impacts with other belt objects, and as such represent the source of most iron meteorites. Sideritic asteroids, classically called M-type asteroids, are probably the richest and most sought after of bodies when it comes to minerals. Planetary economies are often maintained by the mining of these bodies, and industrial bases often rely on Siderites for raw materials in the manufacture of many items. |
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Silicaceous Type As a solar system forms, a population of asteroids might form close enough to the young and active sun so that they become differentiated bodies. These Silicaceous asteroids are heated sufficiently by the electromagnetic currents so that minerals will become separated, much like the process experienced by larger worlds due to their internal heating. As the sun begins to stabilize and cool down, what is left is a rocky body that typically has an olivine crust surrounding a nickel-iron alloy core. |
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Carbonaceous Type Rich in carbon, these bodies are largely pristine and unchanged objects, relics from the formation of their solar system. Rich in organic compounds, they are fairly reddish in coloration, and may contain sizable reservoirs of volatiles such as water ice. They are typically found in the outer most regions of their inner system region, although gravitational scattering over time can of course produce some highly eccentric orbits. |
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Oortean Type Throughout recorded history, and quite likely a good deal before it, comets have long been apparitions to frighten humans, to inspire them, and to serve as heavenly messengers of a sort. No other celestial body has caused such wide spread panic in a human population, or has so effectively changed the course of history. In many ancient Earth cultures comets were seen as harbingers of doom. Others saw them as the announcers of kings and emperors. It was not until comparatively late in human history that anyone began to truly wonder about the true physicality of comets, and it was not until even later that anyone came remotely close to the truth. Although classically known as comets, these small worlds are classified as Oortean bodies. The name is derived from the Oort Cloud, the reservoir that could be viewed as the last remnants of the planetary accretion disk, from which all other bodies in the solar system formed. All comets originate from this region, although their final orbits are often shaped by planetary encounters as they pass through the solar system. The gravity of passing stars can actually have a marked effect on comets in the Oort Cloud, and even a seemingly small nudge is enough to send them on a course towards their parent star. But their initial orbits are long and drawn out, and simply to reach the inner regions of the solar system can take hundreds of thousands of years. But once they do begin to pass through the more populated regions, planetary gravity can effect their orbits just as easily. Some comets will eventually find themselves in fairly stable long term orbits of hundreds of years, while others can be trapped in an orbit that is only a few years in length. Many other comets pass through the solar system only once, moving on a sun-grazing path that will eventually shoot them out of the solar system all together. And still others will even impact their sun. Of course, Oorteans are also a threat to inhabited planets. Unlike asteroids, comets can appear unexpectedly, and often undetected until it is too late. Evidence of impacts on Gaian worlds by comets are common, including Earth. Although asteroids, usually of a bit sterner composition, can do more damage, comets are still very dangerous. One famous example is the Tunguska Event of 1903 AD, on Earth, in which a fragment of a short period comet impacted the northern Siberia region. Although the area was unpopulated, the blast was witnessed by thousands hundreds of miles away, and the resulting dust cloud from the air burst reflected sunlight down around the planet well after the midnight hours. |
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Centaurian Type A minor planet whose orbit around its parent sun lies typically between 5 and 30 AU, though it may extend inward almost as far as 1 AU or outward beyond 40 AU. The orbits of the Centaurs are dynamically unstable due to interactions with giant planets, so they must be objects in transition from a large, outer reservoir of small bodies, the Kuiper Belt, to potentially active, comet-like inner solar system objects. Known sizes range from a few tens to a few hundreds of kilometers across. Their composition is intermediate between that of comets and ordinary asteroids; indeed, the first object to be called a Centaur, Chiron of the Sol System, is often also classified as a comet following the discovery of a coma around it. Clearly, in many cases a cut-and-dry classification scheme is not always successful when confronted by some of the worlds that are to be found. Were any Centaur to be perturbed into an orbit that approaches its local sun, it would become a truly spectacular comet, many times brighter than any seen in historic times. |
