settled-reach/wiki/star-systems/GJ-876/index.md

Koskinen's Reach

GJ 876 | M-type | north_reach

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System Profile

Star	M5 · 15.3 ly
Bodies	0 habitable · 2 inhabited
Gates	2 aperture · spur_end
Settlement	wave_3
Industries	fusion_fuel, metallic_ore, agricultural_produce, processed_food, hospitality, financial_services, legal_services
Exports	processed_food, financial_services
Imports	electronics, consumer_goods, medical_goods, refined_metals, chemicals
Population	—

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Eino Koskinen led the Wave 3 prospecting expedition that established this spur, and the name he chose was honest about what he had found: the outer edge of explored territory, the extent of the reach from where he stood. Koskinen's Reach is a spur end in every sense of the term. Both of its neighbors — GJ 3820 and GJ 661A — are themselves unsettled or barely settled, unwritten into the reach's economic fabric. This system connects to no significant hub in any direction. It is a place where people who chose frontier over integration built something three hundred years ago and have maintained it since.

The star is an M5, and it is part of a binary pair — the companion orbiting at a distance that makes the orbital dynamics complex enough to require active management of the station's own long-term trajectory. The binary geometry is one reason this system was interesting to Koskinen's expedition: the gravitational interactions have shaped the system's planetary bodies in unusual ways, concentrating mineral deposits in zones that would not exist in a single-star system. The planet that Koskinen's team surveyed first is not habitable, but it is resource-rich, and "reach" proved to be both a geographic description and a commercial one.

Three hundred years of relative isolation has produced a community with strong internal coherence and a somewhat suspicious orientation toward outsiders. Finnish in its founding heritage — Koskinen recruited from Finnish-heritage settlement pools, following Wave 3 patterns of cultural consolidation — the community has remained culturally stable in ways that some observers attribute to its isolation and others attribute to deliberate choices made by successive generations. Finnish is widely spoken. Community governance is based on council structures that trace their procedural lineage to the original expedition charter.

The resource extraction economy has operated continuously since the founding but has never scaled to the levels that would attract corporate acquisition. The deposits are real but not spectacular; the transport costs to any significant processing hub are high; the community has found a sustainable equilibrium at a scale that makes outside investment unattractive. This suits most residents, who are not looking for outside investment.

There is something unusual in the binary star system that long-term residents have documented but not fully explained: a periodic disruption in certain navigational reference systems that occurs on a roughly seventeen-year cycle, coinciding with the binary stars' closest orbital approach. The effect is minor and well-understood in practice. What causes it precisely is still debated in the technical literature.

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Supply Dependency

All technical goods and manufactured equipment inbound via one of the two apertures, with the supply chain routed through whichever adjacent system (GJ 3820 or GJ 661A) has the more reliable current transit schedule. Neither adjacent system is a significant hub; Koskinen's Reach effectively relies on transit passing through one stub to reach the broader reach network. This routing is slow and expensive. The community mitigates it through high local self-sufficiency in consumables.

Faction Notes

The Koskinen Community Council is the primary governing body — a consensus-based structure with rotating membership, drawing from the system's several settlement clusters. There is no Assembly presence; the nearest Assembly office is multiple hops toward the inner reach. The Council handles everything from infrastructure to inter-family disputes through the same deliberative process. Outside observers sometimes note that this works because the community is small enough that everyone knows the stakes of every decision.

Silence Topic

The navigational disruption that occurs during the binary stars' periapsis is documented in formal technical reports but the underlying mechanism is not agreed upon. One minority hypothesis suggests it involves the horizon station infrastructure in ways that are not fully understood — that the aperture stability is marginally affected during the event. The Council discusses this internally; it has not been elevated to any formal inquiry because nothing has gone wrong yet.

Silence threshold: investigation_depth

Narrative Hook

The seventeen-year periapsis cycle is due in eight months, and a researcher from a university at Johannsen's Star has arrived with credentials and a data-collection proposal — but their credentials check out too perfectly, and their research questions are oriented toward the horizon station itself rather than the binary orbital dynamics they claimed to be studying.

Calibration Note

Binary-type system at hop 4 with spur_end topology creates genuine narrative isolation — neither adjacent system (GJ 3820, GJ 661A) is written, so this page is designed to stand independently without referencing them as developed communities. Wave_3 founding at this level of isolation is plausible for a prospecting expedition that found viable resources but not spectacular ones.

Celestial Bodies

Orbit	ID	Name	Type	Inhabited	Pop	Mass	Gravity	Year (d)	Day (h)	Atmo	Biome	Hydro	Economy	Settlement	Industrial
1	GJ876b	—	planet	no	—	terrestrial	0.28g	3	72.0	none	barren	none	—	—	—
2	GJ876c	—	planet	no	—	terrestrial	0.52g	10	240.0	none	barren	none	extraction	—	—
3	GJ876d	—	planet	no	—	terrestrial	0.35g	28	672.0	thin	frozen	ice	—	—	—
4	GJ876e	—	planet	no	—	terrestrial	0.28g	80	1920.0	none	frozen	ice	—	—	—
5	GJ876f	—	gas_giant	no	—	gas_giant	—	400	10.0	dense	—	—	—	—	—
↳ 5.1	GJ876f-1	—	moon	no	—	dwarf	0.05g	5	120.0	none	barren	none	—	—	—
↳ 5.2	GJ876f-2	—	moon	no	—	dwarf	0.03g	12	288.0	none	frozen	ice	—	—	—
6	GJ876g	—	planet	no	—	terrestrial	0.20g	1400	18.0	none	frozen	ice	—	—	—
7	GJ876h	—	planet	no	—	dwarf	0.10g	3200	20.0	none	frozen	ice	—	—	—
8	GJ876-belt	—	asteroid_belt	no	—	—	—	—	—	—	—	—	—	—	—
9	GJ876-oort	—	oort_cloud	no	—	—	—	—	—	—	—	—	—	—	—

Stations & Facilities

ID	Name	Type	Orbits	Population	Economy	Governance	Docking	Gate	Districts
GJ876-oort-S1	Halti	horizon	GJ876-oort	—	transit	—	major	yes	1
GJ876c-S1	Kuhmo	industrial	GJ876c	25M	extraction	—	standard	no	1