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Koukotsu System

The Koukotsu System is a star system that is apart of the Yamatai Star Empire and is located in the Yugumo Cluster. In YE 43 the system was added as a member system of the Motoyoshi Colonial Sector.

Koukotsu means “Ecstacy” in Yamataigo (邪馬台語).

The Senator representing the system is Takagawa Hitomi, as of YE 43.

The Flag

The Flag of the Koukotsu System is below.

Flag of Koukotsu

A Home in Paradise

The second planet in the Koukotsu System is the world most refer to with this system in mind. It is a lush tropical paradise world with extensive resort developments, casinos, and luxury accommodations and services. Development continued during the short reign of the United Outer Colonies and continued after the system was reintegrated into the Yamatai Star Empire. It is a common shore leave stop for the Star Army of Yamatai, especially the First Expeditionary Fleet. It is one of the most heavily populated systems in the Yugumo Cluster and with continued development and cultivation, it is expected to continue to blossom.

The Yamatai Star Empire placed global communications networks of Emrys Satellites into orbit of all of the system's terrestrial worlds in YE 36.


More facts about the Koutkotsu System are listed below.

The Paradise System of the Motoyoshi Colonial Sector

About the Koukotsu System's Stars, Planets and other features.

The Koukotsu Stars

The heart of the Koukotsu System:

The Koukotsu Stars
System Registry Motoyoshi-K-950 (K-1) Motoyoshi-K-951 (K-2)
Star Names Koukotsu A Koukotsu B
Type M2 V Red Dwarf (A) M1 V Red Dwar (B)
Distance Central Star 8.86 x 106 km (0.06 AU)
Radius 2.90 x 105 km (A) 2.84 x 105 km (B)
Surface Temperature 3100K (A) 3200K (B)
Average Mass 6.77 x 1029 kg (A) 6.36 x 1029 kg(B)
Luminosity 1.01 x 1025 W (A) 1.13 x 1025 W (B)
Number of Planets 5

Koukotsu I

Koukotsu I is a rocky, desolate, near-star world and an inhospitable atmosphere of helium, hydrogen and potassium that is driven by solar winds of the primary star. There are old helium-3 extraction sites and automated mining equipment on the surface which was placed by Motoyoshi Fleet Yards. These sites are not active as of YE 43, but they fall under the ownership of the Yugumo Corporation.

Koukotsu II

Koukotsu II4) is a beautiful paradise world with nine planetary rings. Of the five worlds in this system, this one is the most densely populated and is considered the system capital. Vast rainforests cover the landmasses, and the planet is famous for its white-sand beaches and sparkling crystal seas. The planet is prone to a rather eventful hurricane season which is being controlled through atmospheric manipulation through a series of close-orbiting satellites placed by the Star Army of Yamatai in YE 29.

The planet has several colonies including; Paradise City, Koukotsu Resort Complex, Mazu Beach, and Kiyoko Beach. 5) As of YE 43, the planet reported a population of 256,000,000 which is currently rising at a rate of 3% per YE.

There was an Origin Mart placed on Koutkotsu II in YE 34. In YE 43 the Juugoya Cooperative has continued to support and operate several farming and aquaculture collectives on the planet.

Koukotsu III

Koukotsu III6) is a planet of primarily dense coniferous forestation in areas not covered by the heavy glaciation that covers nearly 77% of the surface. It has a breathable atmosphere, moderately available resources, and for the most part, is locked in an ice age likely caused by a lengthy period of vulcanization which projected heavy amounts of ash into the atmosphere.

In YE 34, Origin Industries established a large testing and training complex on Koukotsu III for the training of test pilots and OriSec personnel, as well as the testing of new prototypes and other equipment.

In YE 36, a Bravemart opened in the planet's civilian starport.

There are several colonies on the surface of Koukotsu III; Point Hoshi, Point Horizon, Point Crystal, and as of YE 43, the planet reported a population of 45,000,320 citizens, with an expected growth rate of 1.5% per YE.

Koukotsu IV

Koukotsu IV7) is a rather unremarkable gas giant with fifty-five small moons and four large moons.

Koukotsu V

Koukotsu V8) is a rather unremarkable gas giant with planetary rings. It has eleven large moons.

The Presence of the Star Army of Yamatai

This system is actively patrolled by the First Expeditionary Fleet of the Star Army of Yamatai.

Aquarius Star Fortress is a unique First Expeditionary Fleet Zodiac-Class Star Fortress positioned in the Koukotsu System. It features amazing aquatic designs and internal aquarium environments. It is referred to as the “Guardian of Paradise”.

Export and Trade

The Kouktsu System exports and trades a lot of goods.

Primary Industries
farming, travel and tourism, bioindustry, textiles


The population of the Koukotsu System is primarily Minkan; there are some Lorath and Nepleslian that have remained after the transition from the United Outer Colonies back to the Yamatai Star Empire. The people of Koukotsu are known for their hospitality, as a tourism-driven economy, they rely heavily on the economy driven by visitors to their world. They have been very supportive of the establishment of Aquarius Star Fortress in YE 43 as that it has increased the presence of the Star Army of Yamatai.


These Characters are present in the system:9)

Kára KuroganeActress, Idol, Model, SenatorFemaleNekovalkyrja


The Koukotsu System is connected to the rest of the Yamatai Star Empire by PAINT. The only way to reach this location is by Starship or other craft.

RP Opportunities

Great roleplay opportunities.

  • Take a vacation or shore-leave here.
  • Have a paradise romance.
  • Explore the tropical rainforests.
  • Establish a corporation or define a location.

Local Rumors

Maybe true, maybe not.

  • There are mermaids that swim in the planet's oceans similar to those rumored to be on Aquarius Star Fortress.

OOC Notes

Andrew updated this article on 2020/03/05 17:25.

Previous versions by Wes and Kai.

Flag and Aquarius Unit Badge made by Wes

This was approved by Wes in this thread.

Map Locations
Map to UseKikyo Sector
Map Display NameKoukotsu
Map Coordinates2478,1144
Map ImportanceMinor RP Location
Map Marker
Map Tooltip ContentThe Paradise System of the Motoyoshi Colonial Sector
Show label?yes
Marker AnchorCenter Center
Places of the SARPiverse
Place Categoriesplanet, star system
Terrestrial World Orbital Radius: 2.89 x 107 km (0.19 AU) Period: 9.11 x 102 hours (0.10 earth years) Physics: Small iron/silicate Hydrosphere: 52 % water, 6 % ice Atmosphere: Breathable Special: 9 Planetary rings
colonies were listed on the original page, will eventually need to be submitted as locations
Terrestrial World Orbital Radius: 4.12 x 107 km (0.28 AU) Period: 1.56 x 103 hours (0.18 earth years) Physics: Small iron/silicate Hydrosphere: 33 % water, 20 % ice Atmosphere: Breathable Special: Thin planetary wings
Orbital Radius: 5.82 x 107 km (0.39 AU) Period: 2.61 x 103 hours (0.30 earth years) Gravity: 13.23 m/s2 (1.35 x earth) Special: 55 small moons, 4 large moons
Orbital Radius: 2.97 x 108 km (1.99 AU) Period: 3.01 x 104 hours (3.44 earth years) Gravity: 34.42 m/s2 (3.52 x earth
Struct list will show when someone lists this as a location

system/koukotsu.txt · Last modified: 2023/12/20 18:22 (external edit)