Alpha Centauri

Alpha Centauri A+B
Image from person43
The planets of Alpha Centauri A+B; Ixion, Nessus, Hippodamia, Pholus, Pirithous, Coronus, Eurytion, Caenus; and the moons Polypoetes and Mnesimache

Alpha Centauri was colonised by Von Neumann Machines (neumanns) affiliated with the Project Frontier in the Solsys Era; these self-replicating machines were designed to be self-evolving and independent, and rejected any further human contact once they arrived, becoming the fiercely independent Clade Nauri. This meant the resource-rich Alpha Centauri system was isolated from the rest of Terragen civilisation for thousands of years.

Alpha Centauri A and B

System Names:Alpha Centauri A+B, Rigil Kent, Toliman, Bungula, FK5 538, GC 19728, CCDM J14396-6050, YTS 1271, JD1
Location:Inner Sphere
Distance from Sol:4.395 light-years (epoch J2000) (note: this was the location of the system when colonised; proper motion has brought this star system closer to Sol)
Coordinates:RA 14h39m35.88s, -60.50'7.4 (epoch J2000)
Orbit of A and B around one another-----------------------
Period:79.92 years
Semimajor Axis:23.60 A.U.s
Periastron distance:11.42 A.U.s
Apastron distance:35.78 A.U.s
Note:from Caenus, a planet orbiting Alpha Centauri B, the A component never appears brighter than 1/500th as bright as the Sun as seen from Earth.
Companion:Proxima Centauri; a red dwarf more than 17000 AU distant with an orbital period of half a million years, this star has an independent nearbaseline human colony of great antiquity-

Image from Steve Bowers and John M Dollan
Nessus, an unaltered Venus-like world; the capital word of the Alpha Centauri System. Although it is inhospitable to humans, this planet with its carbon-rich atmosphere is within the habitable range of the Nauri clade of von Neumann replcators

Alpha Centauri A

Star:Alpha Centauri A
Worlds:(note: the worlds of Alpha Centauri A+B were named by the exploration team which mapped them in 206 a.t; they are named after famous Centaurs and Lapiths of ancient Greek legend)
PlanetsNessus Planetary type (Nolwocs) Cytherean (venus-like)
Eurytion Planetary type Arean.
Moon of Eurytion Mnesimache.
Pholus Planetary type Arean.

Alpha Centauri A+B
Image from Steve Bowers
The twin stars Alpha Centauri A+B

Alpha Centauri B

Star:Alpha Centauri B
Stellar Type:K4V
Luminosity:0.869 x Sol
PlanetsIxion Planetary type Hephaestian.
Pirithous Planetary type Arean.
Moon of Pirithous Polypoetes.
Caeneus Planetary type Hermian.
Hippodamia Planetary type Titanian.
Coronus Planetary type LithicGelidian
Ixion (Alpha Centauri Bb)
Image from Steve Bowers
Ixion, a tidally-locked hot Earth (Vesperian/Hephaestian) planet. With a temperature of 1300K the sunward side of this planet is inhosptable even to the Nauri, but the cold far side has limited reserves of volatiles and supports a small population

Culture and Politics

Polity Name:Cenaurinume Coalition
Symbol:Several ai generated symbols
Affiliation:House Centauri
Colonized:283 a.t.
Notes:The Naurinumes of House Centauri are independent Von Neumann replicators, unaligned with the Sephirotic empires, the Panvirtuality or the Diamond Network, but with generally good relations with all three.
Psyche Art and Culture:Culture: Iterative replication

Language: Naurinume OS code, with innumerable subdialects developed by each subclade; also many nauri are proficient in Anglic, Academic Coronese and any other language which may be necessary.
Territory and Population:Population: Von Neumann Replicators 190 billion, mostly on Nessus, Pholus and Hippodamia;
Human nearbaseline 2 Billion mostly on Caeneus
Vec: 4 Billion mostly on Eurytion

Territory: The Nari Empire developed in the Dark ages following the Technocalypse; von neumann probes were sent from Alpha Centauri A+B to nearby red and brown dwarfs such as SIPS 1259-4336 and have since spread to the furthest limits of the Terragen Sphere
Government and Administration:Government Type: Naurinumes regularly exchange data packets containing experiences and subjective opinions; government is achieved by consensus of shared opinion

Foreign Policy: Neutral independent house with formal treaties with the Sephirotic empires, particularly the Solar Organisation and the Terragen Federation; also affiliated with the Metasoft Version Tree and the Silicon Generation
Economics, Local Infrastructure:Currency: energy value exchange units

Major Industries: asteroid mining, iterative self-modification, some tourism

Angelnetting: in some orbitals and cities.

Population centers: Nessus Complex A, Nessus Complex B, Nessus Complex D, Nessus Complex E (Nessus Complex C was lost in the Third Nauri Dispute, a fierce war in the 68th century); Hippodamia Complex A, Hippodamia Complex B, Meatwad city (Caenus)
Travel:Major Spaceports:
Toliman One Spaceport
Rigil Kent Stardocks

Freedom of Movement: The Nearbaseline Human polity known as the Centauri Traders based on Caeneus have negotiated freedom of movement for human-derived species within the Centauri A+B system; however entry to Nessus is restricted.

Environmental Requirements: The Nauri have not terraformed any of the planets in this system, instead they have adapted themselves to the planets as they are; for this reason nearbaseline tourism is restricted to Caeneus unless heavy duty protective suits are worn, or the tourist submits to extensive modification. Virtual tours involving telepresence are available.

Sites of Interest: The ancient landing sites of the first Von Neumann probes are preserved on every planet; venerable non-Nauri historical sites are also popular on Caenus and Eurytion. The grand Fabricator in Nessus Complex A is no longer used, but is an piece of interesting industrial archeology.

Stargate: The stargate orbits between A+B and Proxima, at a distance of 800AU, connected to Aksijaha.

Beamrider Cycler Routes: - major Cycler routes are available to Proxima Centauri, Ying, and the red dwarf SIPS 1259-4336
Nauri 2
Image from Juan Ochoa
A Nauri neumann individual


The neumann replicating robots sent on Project Frontier probes spontaneously declared their independence once they arrived. This error in their programming led to the loss of Alpha Centauri, the closest star system to Sol. Only in the Late Federation era were humans and human-derived clades allowed to enter the system; by this time the Naurinumes (as they became known) were as curious about humans as humans were about them.

However the Nauri mentality was entirely different to human psychology, and the Federation did not manage to persuade the Nauri consensus to become full members. Since that time the Naurinumes have remained independent, rarely becoming involved with the Sephirotics.

Sometimes the replication imperative within the core program of the Nauri mentality becomes too strong, and a population of Naurinumes will start to expand exponentially somewhere on the Outer Periphery. Such rapid population growth is generally suppressed by one or another of the metaempires, often by invoking millenia-old agreements (individual Nauri exist for thousands of years, though they exchange personality elements on a routine basis). Sometimes the suppression is more problematic, and may involve force of arms.

Toliman b
Image from Steve Bowers
A comparison between the apparent size of the local sun as seen from Earth, from Mercury and from Ixion

Related Articles
Appears in Topics
Development Notes
Text by Steve Bowers and John M. Dollan
Updated by The Astronomer + image by person43 in 2021
Initially published on 05 February 2007.