settled-reach/wiki/star-systems/GJ-660A/index.md

Seongho

GJ 660A | G-type | east_reach

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System Profile

Star	G · 33.2 ly
Bodies	0 habitable · 2 inhabited
Gates	3 aperture · junction
Settlement	wave_3
Industries	fusion_fuel, metallic_ore, financial_services, insurance, legal_services, lattice_grade_material
Exports	financial_services, legal_services, lattice_grade_material
Imports	processed_food, electronics, consumer_goods, medical_goods, refined_metals, heavy_equipment
Population	—

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Seongho is a junction system at hop 7, three hundred years old, connecting the Hwaseong corridor inward (GJ 1125) to Binh Trang outward (GJ 17) and the Tình Yên dead-end branch (GJ 107A). The planet it administers — Seongho Prime, or simply "the ground" in local speech — is geothermally overactive by any measure: a world of black-rock plains fractured by heat vents, with a thin nitrogen-CO2 atmosphere that settlers never managed to breathe directly and never seriously tried to. All habitation is sealed. All infrastructure runs on geothermal tap.

The Korean-heritage founding community arrived in Wave 3 from what had been a well-established corridor segment around Hwaseong, and they chose the site deliberately. The survey reports were unambiguous about the geothermal potential. Where another community might have seen an environment problem — a world that cannot be terraformed at practical cost, sealed habitation indefinitely, no surface agriculture — the Seongho founders read an energy opportunity, and they were right.

Geothermal export has been Seongho's primary economic activity for two and a half centuries. The tapping infrastructure is now extensive: over three hundred active bore installations, a distribution network that feeds not only all local sealed habitats but several transit facilities and the gate cluster itself, and an export pipeline that feeds conditioned energy product — standardized power cells and thermal conversion units — to ships transiting the junction. Vessels stopping at Seongho to recharge pay junction fees that, combined with geothermal product sales, make this one of the better-capitalized systems at this distance from Gateway.

The culture has organized itself around heat management as both a practical discipline and a social value. Seongho's engineering schools specialize in thermal systems. Their civic architecture prizes efficient heat distribution in a way that visitors from cooler systems find unusual — the interiors of Seongho habitats maintain precise temperature gradients by zone, and residents navigate between zones with an unconscious awareness of thermal comfort that outsiders describe as "reading the air." The phrase for a well-run household, onda-ga jal dodda, translates approximately as "the warmth flows right."

Three apertures give Seongho an unusual position for a hop-7 system: it is not at the end of anything, and traffic through it is constant. The community is accustomed to transient populations, and the hospitality infrastructure reflects this — there are three transit hostels, a competent medical facility calibrated to handle travelers who have been in deep-reach conditions, and a market district that stocks items from across the east reach corridor.

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Supply Dependency

Seongho is energy-independent to an extraordinary degree; the geothermal infrastructure produces substantially more power than local needs require, and the surplus is the primary export. Food is imported, primarily from Hwaseong (GJ 1125) and Binh Trang (GJ 17), as the sealed-habitat conditions do not support agriculture beyond hydroponic supplement. Manufactured goods and technical components for bore maintenance route inward through Hwaseong. The transit junction generates service-sector income sufficient to offset most of the food and equipment import costs.

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Faction Notes

The Thermal Authority administers all bore infrastructure and energy distribution, a role that gives it effective control over the physical survival of every habitat in the system. The Authority's board is drawn from the founding technical families, though the governance rules require rotating representation from newer resident populations. The Authority's decisions about energy pricing — internal and export — have significant downstream effects on Seongho's political life, and the board meetings are public, which they have sometimes regretted.

The Junction Transit Cooperative manages gate operations, transit hostel licensing, and the market district under a charter from the system's elected council. It is the second most powerful institution in the system and has periodic jurisdictional disputes with the Thermal Authority over infrastructure priority — specifically, which competing demand on bore output gets satisfied first when the grid runs close to capacity.

The Residents' Assembly is the system's elected legislature. At three apertures and a growing transient population, the question of who qualifies as a resident for voting purposes is a standing agenda item that the Assembly has resolved and re-reopened four times in the last fifty years.

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Silence Topic

The bore survey data that underpins Seongho's energy production projections was last fully audited thirty years ago. Since then, the Thermal Authority's internal monitoring has detected a pattern of declining output yield from the oldest bore installations in the eastern field — a trend that, if it represents structural exhaustion of those thermal sites rather than cyclical variation, implies a reduction in total export capacity within one to two generations. The Authority's board has access to this trend data. The elected council and the general population do not.

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Narrative Hook

A Thermal Authority bore technician who has spent twenty years monitoring the eastern field retires and, having received no satisfactory response from management about what she believes are signs of long-term structural depletion, contacts a journalist at one of the transit corridor's independent news services.

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Calibration Note

The READ-ONLY System Profile shows "G" as the star classification — lowercase, ambiguous, likely a data artifact from the catalog entry. The existing header lists M-type, which the briefing also specifies, and the world character described (geothermally extreme, non-breathable atmosphere) is more consistent with a dim or complex primary than a true G-type; the classification is retained as-is per the existing header. Junction with 3 apertures at hop 7 is consistent with the described role as a corridor linking node. Wave_3 Korean heritage aligns with the eastern reach's mid-wave expansion history.

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Celestial Bodies

Orbit	ID	Name	Type	Inhabited	Pop	Mass	Gravity	Year (d)	Day (h)	Atmo	Biome	Hydro	Economy	Settlement	Industrial
1	GJ660Ab	—	planet	no	—	terrestrial	0.30g	20	18.2	none	barren	—	—	—	—
2	GJ660Ac	—	planet	no	—	terrestrial	0.56g	70	24.8	none	barren	—	—	—	—
3	GJ660Ad	Seongho Prime	planet	yes	95K	terrestrial	0.94g	330	29.4	thin	volcanic	—	energy	urban_concentrated	energy_export
4	GJ660Ae	—	planet	no	—	terrestrial	0.52g	700	33.6	thin	cold_arid	—	—	—	—
5	GJ660A-belt	—	asteroid_belt	no	—	—	—	—	—	—	—	—	—	—	—
6	GJ660Af	—	gas_giant	no	—	—	—	2000	11.2	gas_giant	—	—	—	—	—
↳ 6.1	GJ660Af-m1	—	moon	no	—	dwarf	0.08g	5	129.6	—	frozen	—	—	—	—
7	GJ660Ag	—	planet	no	—	terrestrial	0.40g	4800	37.8	trace	frozen	ice	—	—	—
8	GJ660Ah	—	planet	no	—	terrestrial	0.28g	10500	43.4	trace	frozen	ice	—	—	—
9	GJ660Ai	—	planet	no	—	dwarf	0.11g	23000	25.6	none	frozen	ice	—	—	—
10	GJ660Aj	—	planet	no	—	dwarf	0.10g	46000	22.4	none	frozen	ice	—	—	—
11	GJ660A-oort	—	oort_cloud	no	—	—	—	—	—	—	—	—	—	—	—

Stations & Facilities

ID	Name	Type	Orbits	Population	Economy	Governance	Docking	Gate	Districts
GJ660A-oort-S1	Seongho Horizon	horizon	GJ660A-oort	950	transit	—	major	yes	1

Topology

• Hop Distance from Gateway: 7
• Adjacent Systems: GJ 17, GJ 1125, GJ 107A