ETI: Sol System Economics

The Sol System is divided by culture, time, and distance. Despite this, ties of commerce connect many worlds into various loose networks. 

The worlds of the "Inner System", including Mercury, Venus, Earth, and Mars, can be spoken of as a unified community in some respects. They are all relatively close together - 2.5AU at most, so they maintain robust trade relations and frequent contact. Mars dominates the region by dint of its population and food production. It is held back in some ways by its essentially agrarian, theocratic society, and has much less presence in space than one might imagine. As a result, most interplanetary commerce is actually managed by Chandra Colony or by Belter contractors. The Free Luna Soviet and Chandra maintain a healthy cooperative relationship, trading technology and food as necessary. Luna regards Chandra as excessively capitalist, while the Chandrans see Luna as too rigid and meddlesome, but both regard the Saturn Federation as the primary threat to their continued independence. Both maintain loose but friendly relations with Dar-ul-Muraqab. Mars supplies food to most of the Solar System, in exchange for advanced technology from Chandra, medical technology and scientific knowledge from the Free Luna Soviet, and transportation from the Belt League. The "Right Hand Mareekhi" are a minority faction in the UMA government who want to launch a crusade to bring the entire solar system, starting with the Saturnians, under Mareekhism.

The Outer System is far too spread out to be spoken of in any unified way. Each of the gas giants is a long distance from anything else, and the accompanying clouds of satellites large and small make each one into a solar system of its own. Nevertheless, the worlds of the Outer System do interact.

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  The Saturn Federation maintains a client-state relationship with the "Unaffiliated Martian States", supplying them with technology and manpower in exchange for food. This is the primary friction point between the UMA and Saturn, quite apart from the serious religious differences. The two states are currently at peace, but relations are usually fairly tense. Official Saturnian policy is that the Unity is the heir to the old Sino-American Alliance, and thus the rightful ruler of the Solar System. The Saturnians will constantly be angling to increase their influence in a region, directly or indirectly.

• The Belt League trades refined metals and organics to Free Luna, Chandra, Triton, and Mars, as well as supplying small freight and transportation between most worlds in the Solar System. The Belt League has official relations with the Saturn Federation, but the Wild Belters have a long-running guerrilla war against the Saturn Federation in Jupiter's Trojan groups. The Belters are always in the market for additional ship components and weaponry, as they are badly outgunned by the Saturnian Navy.

• Europa, Triton, and the Kuiper Settlements are all isolated by distance and inclination. They tend to be one-commodity states, whether it be Helium-3 or black market goods. Most of the states in the solar system maintain some sort of relations with these outliers, but none of them are as close as the ones in the core. Likewise, these worlds are farther from one another than to the Inner System, so they hold no special affections for one another. They are united in their distrust of the Saturn Federation, at the very least.

There are three primary physical currencies in use in the Solar System. The specific currency used can vary wildly by time and place, and may produce social reactions based on local conditions and events. Outside of currency, refined metals remain an accepted method of commerce

• The Martian Dinar is a small round coin used across Mars and the inner planets, especially by Dar-ul-Muraqab. It is available in the usual increments, and is regarded as an old-fashioned but stable currency. It is stamped with various images such as religious symbols, portraits of saints, or scriptures in Arabic. Offworld transactions are often conducted electronically, especially on Chandra. Actual coin currency is much preferred on Mars itself, where electronic transfers, financial institutions, currency speculation and even paper money are regarded with considerable suspicion.

• The Ceres Dollar is in use throughout the Belt League and the smaller communities of the outer Solar System, as well as by Chandra. It is managed and guaranteed by the Primary Bank of Ceres, in the Main Belt. It is primarily traded in electronic form, but the currency is also available in polygonal coins of various sizes, mostly made of rare metals like platinum, iridium, and molybdenum that can be found in the Belt.

• The Saturnian Credit is used almost exclusively by the Saturn Federation and its allies among the unaffiliated Martian states. It can be converted in most places, however, for a substantial fee. The Credit is usually traded electronically, but can also be transacted using "paper" money which is loaded with tracking and anti-counterfeiting measures.