Iouo (world)

Iouo/Iouo (Magyar 0624)
Classic Era (1116)	A79A96B-E Starport A Excellent: Starship Construction, Overhaul, Refined fuel Size 7 Medium (11,200 km, 0.70g - 0.94g) Atmosphere 9 Dense (tainted) Hydrographics A Water World 100% Population 9 High (8 billion) Government 6 Captive Government/Colony Law B Extreme Law (control of movement) Tech Level E High Stellar (anti-grav cities)
See also	UWP
System Details
Primary	K3 V M7 V
Planetoid Belts	0
Gas Giants	0

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Jump map from Travellermap.com

Iouo is a high-population, industrial water world, which has 90% or more of its surface covered in an ocean of water and a billion or more sophonts in population size.

• The inhabitants of this world live on the roughly 10% of exposed land mass, in underwater colonies, on city ships, or similar arrangements.
• As an industrial world, this planet has well-developed manufacturing and processing industries. Manufactured goods are a major export item.
• Its economy is rapidly growing and living conditions are expected to rapidly improve barring outside forces.
• This is a "high technology" world with technology achievements at, near, or above the standard for Charted Space.
• This world toils under the control of a military government with conditions reflecting that situation, including curtailed civil rights and limited freedoms.
• It is a member of the Solomani Confederation in the Iouo Subsector of Magyar Sector.

• This world has a Naval Base, usually associated with military starships.
• This world has a Military Base, usually associated with military ground forces.
• About 60% of the population is composed of Aslan.
• About 40% of the population is composed of baseline humans and other non-human sophonts.
• This world has colonies at:
  • Feayu (world)
  • Yoeahti (world)
  • Wieaaw (world)

Description (Astrography & Planetology)

This system is part of the Acaran Snarl, the largest main in the Magyar Sector and the second largest main in the entire Solomani Sphere.

Stellar Data

Iouo has two stars in the star system.

Iiyaoa
	Type	Category		Mass (Sol)	Temperature (K)	Luminosity
	K3 V	Main Sequence (Dwarf)		0.78	4600 - 4830	0.41911
	Unit	Diameter	Safe Distance	Habitable Zone	Jump Shadow	M-Drive Limit
	AU	0.007	0.0537	0.65 - 1.18	0.7	7
	Orbit #	*	*	3	2	6
	Remarks
Hleaeiy
	Type	Category		Mass (Sol)	Temperature (K)	Luminosity
	M7 V	Main Sequence (Dwarf)		0.09	2630 - 2680	0.00022
	Unit	Diameter	Safe Distance	Habitable Zone	Jump Shadow	M-Drive Limit
	AU	0.0011	0.0012	0.02 - 0.03	0.11	1.1
	Orbit #	*	*	*	0	3
	Remarks

Mainworld Atmosphere

The dense oxygen-nitrogen atmosphere is tainted with inert gasses, requiring the use of both filter masks and respirators in order to avoid narcosis in both Aslan and Humans.

History & Background (Dossier)

Iouo was formerly the capital of its subsector. An escalating war of economics and ideologies between it and Havaiikii (Magyar 0523) seemed likely to ruin both worlds. In 1069, sector authorities stepped in, moving the subsector government four parsecs away to Gobi (Magyar 0528), and placing both worlds under military rule. A trade commission was appointed to mediate the economic disputes, but they found that the root of the war seemed instead to be in conflicting political philosophies.

Despite the transfer of the subsector capital, Iouo remains the most important world in the subsector.

World Starport (St)

Iouo has a Class A Starport, an excellent quality installation which includes all the expected amenities including refined fuel for starships, brokerage services for passengers and cargo, and a variety of ship provisions. There is a shipyard capable of doing annual maintenance, overhauls and other kinds of repair, and construction of both starships and non-starships. Most ports of this classification have both a Highport and a Downport.

• There is an associated Imperial Naval Base.

World Population (P)

Iouo has a population of 8,000,000,000 sophonts (billions).

• High Population Worlds like this tend to have huge consumer markets.

World Demographics

• Aslan, 60%
• Human, 40%

World Languages

• Anglic
• Aslan Languages
• Aslanic

Urbanization

Iouo is famed for the Hlalea, 128 model cities with populations of 10 million or more, defined by graceful Aslan architecture. The cities have sprawling, open designs. Eighty-three of them float on the surface of the oceans, 26 are underwater, 17 are gravitic cities and two are orbital structures.

World Economy

Iouo is an important economic power in the region. It is the source of many high-tech goods for New Libdis, Treege and Jingleswelt.

References

This list of sources was used by the Traveller Wiki Editorial Team and individual contributors to compose this article. Copyrighted material is used under license from Mongoose Publishing or by permission of the author. The page history lists all of the contributions.

• Jim Cunningham, John Harshman, J. Andrew Keith, Marc W. Miller, Gordon Sheridan. Atlas of the Imperium (Game Designers Workshop, 1984), . (named)
• Peter G. Celella, James Holden. Solomani & Aslan (Digest Group Publications, 1991), . (dot map provided)
• Gary L. Thomas. "Magyar Sector: Library Data." The Travellers' Digest 14 (1989): 30.
• Randy Dorman. The Deep and the Dark (Mongoose Publishing, 2023), 12, 101-102, 115-116.
• Randy Dorman. Clans of the Aslan (Mongoose Publishing, 2025), 102, 176-177.
• Matthew Sprange. "The Hkiyrerao Passage." Journal of the Travellers' Aid Society volume 13 (2025): 56.