Circumstellar Ring Megastructure

Image from Phil B
The rotating surface of Wadai ringworld would tear itself apart, because the centrifugal forces are greater than the strength of any conventional materials; but a ring of massive particles push inwards to counteract this massive pressure. This has allowed the ringworld to be constructed without the use of magmatter.

A relatively small ringworld around a white dwarf star

Wadai: Data Panel

Location- Distance from Dalim: 17.132 ly (J2000)
- Distance from Sol: 54.37 ly (J2000)
- Constellation: Cetus
Reached: 1681, by colonists aboard the colony ship Amideen.
StarNames Wadai, EGGR 471, GJ 3162, WD 0230-144
Physical characteristics:
- Mass: 0.65 x Sol
- Radius: 8,200 km
- Luminosity: 0.000104 x Sol (bolometric)
- Temperature: 5,375 Kelvin
- Spectral type: DC9
- Age: 4.28 billion years (as a white dwarf)
SystemThe star and the two largest planets were named after the ancient Wadai empire and its two historic capitals. Other planets were named after prominent figures in the Jasmeela Islamic Community.
- Wadai Ring: Rhean Mari-Tepidal Aqua-Gaian Ringworld.
Radius = 1,480,000 km, Width: 17,345 km, Mass = 2 x 10e22 kg
1) Wara: Borean-Neptunian.
Semi-major axis = 6.444 AU, Orbital period = 20.29 years, Eccentricity = 0.083, Mass = 17.89 x Earth, Radius = 4.074 x Earth
2) Abishi: Borean-Neptunian.
Semi-major axis = 15.98 AU, Orbital period = 79.21 years, Eccentricity = 0.196, Mass = 22.08 x Earth, Radius = 4.176 x Earth

System characteristics

The central white dwarf star, Wadai, is a remnant of a star roughly twice as massive as Sol which left the final stage of its hydrogen-fusing phase over 4 billion years ago. Since then, the white dwarf has cooled down to temperatures in the range of the cooler end of G-type stars. In the Current Era, the Wadai system is overseen by Adus D'galla, a group of S1 transapients affiliated with the Sophic League.

The Wadai Ring, the oldest full circumstellar ringworld in the Sephirotics, encircles the star. The ring was constructed with carbon nanotube weave, but even the strongest of conventional materials would have been torn apart by centrifugal force were it not for the additional weight of the counter-rotating mass particle beams, stationary with respect to the rest frame, pressing inwards and balancing the outward pressure of the rotating surface.

This has allowed the construction of a ringworld with respectable surface gravity of around 0.8g using conventional materials instead of magmatter (as ultratech material which was not available when construction started on this ring). The inner surface is split into some 536 sectors, each roughly square in shape and covered with a unique artificial environment. The ring receives natural sunlight emitted from the white dwarf in the center. Its day-night cycle is replicated by a solid ring of PQDA. Early on the entire surface shared a 36 hours-long day-night cycle, but since 5102, most sections have gradually switched to their own cycle, with different (and often non-correlating) lengths of daytime and nighttime, some as short as a few tens of minutes and others multiple standard years-long.


During the period between 1379 and 1925, the Ran system was very active in interstellar colonization, sending tens of starships to colonize new systems over this period. In 1419, a faction within the New Home League, the Jasmeela Islamic Community, contributed to this trend by launching a starship, called the Amideen, on an interstellar flight over 40 light years long towards the white dwarf star WD 0230-144. The journey took 262 years.

During the early years, the colonists established the Wadai League, an organization modeled after the Eridanus League, to govern themselves and the immigrants who would transmit themselves to the system later. It came into contact with a small group of transpients at the nearby star of Dalim, and soon became its client polity. The Wadai civilization owed its achievements to the Dalim transapients, who provided them with transapienttech gifts as the Federation of Sophonts declined. These gifts were crucial in the construction of the Wadai Ring, which began in 2122.

During the First Federation period this cluster of semi-independent colonies became advanced in the design and construction of carbon-shelled structures. Building a series of rotating habitats around the dwarf and the two cinderworlds, the Wadai colonists developed a new, vibrant culture, influenced by elements of the harmonious and musically-dominated lifestyle developed long ago on Oberon, a moon of Uranus. Later contact with the Sophic League and the Stellar Umma led to a rich spiritual and noetic development among the enhanced and augmented sections of society.

Ouaddai Ring World
Image from Steve Bowers
The Wadai Ring is two million kilometres in diameter, and surrounds a white dwarf star which is roughly the same diameter as Earth.
From 4800 to 7600 a.t. Wadai Ring culture was predominantly Mortalist, largely because of close ties with other similar Sophic League and Umma worlds. Both the nearbaseline humans and the posthumans of that world rejected excessive life extension and digital immortality, but chose freely to die of old age, and to go forward into a supposed afterlife which had no physical connection with our own existence. A series of schisms and power struggles in the Age of Crisis, some ferocious and bloody, eventually allowed the Immortalists of the Materialist Tendency to follow the practice of uploading, as part of their transcendental and spiritual development.

The culture of Wadai in the Current Era is a mixture of Mortalism, Islamic beliefs, MPA materialism and cosmopolitanism. The influence of musical culture is still highly important, although subject to rapid changes in style and content.

Image from Steve Bowers
A crop of Euphoric Breadplant growing on Waddai. Geneered crops containing data-rich subjective qualia are often grown for consumption on this world, often used to enhance the user's aesthetic or spiritual experiences.
With large expanses of landscape to explore, the population of Wadai is often mobile, moving in a leisurely fashion from location to location on foot carrying their possessions with them (or accompanied by robotic luggage carriers) . This lifestyle has emerged on several large megastructures, a phenomenon which is known as megastructure migration.
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Development Notes
Text by Steve Bowers
Updated by The Astronomer 2021
Initially published on 02 December 2003.

Fiction about Wadai

Traveler's Notes - Wadai