Cyrannus

Overview

Cyrannus (also spelled "Cyranus") is the name of the solar system containing the worlds of the Twelve Colonies of Man in the Battlestar Galactica video game, published in 2003. This video game was based on the characters and events of the Original Series as it details a young pilot named Adama and his fight in the Thousand Yahren War.

The name has also been used in one Original Series episode, "The Long Patrol", but not to describe a solar system (see the section on the use of the term in the Original Series.

• No aired episode of the Re-imagined Series has used "Cyrannus" as the name of their solar system. Therefore, the official name of the solar system of the Twelve Colonies for the Re-imagined Series is unknown.
• It's not known in the video game whether Cyrannus is a single star with multiple life-bearing planets, or a binary, a trinary star system, or an open cluster of stars.

The Problem of "Cyrannus" and 12 Earth-like planets

While it has been ascertained through searches undertaken from both the surface of the Earth and the Hubble Space Telescope that there are a large number of planets orbiting local stars in our galaxy, most of the planets discovered to date are clssified as gas giants, similar in size and potentialy in composition as the planet Jupiter in our own solar system.

Further, it is believed that there is a very narrow band of space around a star that will encourage the formation of life-bearing planets (the so-called "Goldilocks Zone"). This is a region of space where the heat from the sun is neither too hot nor too cold to prevent the natural development of life through chemical and then organic means.

It is highly improbable that a single star would have no fewer than twelve planets and moons orbiting a star within the "zone of life" for that star. This would indicate that it is doubt the 12 colonies exist within the planetary system of a single star - unless the Colonials have the ability to carry out considerable terraforming; something that is not indicated given their current technological capabilities.

Binary Stars

Binary stars are stars bound by a common gravitational force such that they orbit around a common point in space. Their spectral types can vary quite widely, and it is questionable as to whether all binaries will be capable of producing stable planets due to the degree of gravitational flux between the stars.

Binary star systems can also form the center of hierarchical triple (trinary) systems (a binary system with a third star orbiting both) at a much greater distance.

Cyrannus might be considered a binary star system because such systems, while containing multiple stars, are often referred to by a single name. A binary star system, with stars in the G-K spectral range offer the possibility that each star develops its own Goldilocks Zone and habitable planets therein. The changing distance between the two stars as they orbit each other could conceivably encourage the use of some form of FTL travel to move rapidly between worlds orbiting either star.

Example of a Binary Star System

The Alpha Centauri system is a prime example of both a binary star system and an hierarchial triple star system, a multiple-star system having a single name.

Alpha Centauri comprises a true binary system, Alpha Centauri A and Alpha Centauri B, both of which are of the correct spectral types to sustain life-bearing planets. They in turn are orbited by a third star at a much greater distance (Proxima Centauri), thus making the system an hierarchial triple. Proxima Centauri is classified as a red dwarf, and thus is believed incapable of bearing life-sustaining planets.

Open Star Clusters

Open star clusters, as their name suggests, are groupings of multiple stars in relatively close proximity to one another which are not bound together by gravity (although a star cluster can contain binaries among its number. Due to the number of stars within a cluster, the possibly of several being able to support life-bearing planets might be considered high.

There are several advantages in considering Cyrannus to represent a star cluster (or for the Twelve Colonies of Man to be within an open star cluster:

• A star cluster may present a much large number of stars capable of supporting life-bearing planets
• The distances between stars would be much greater than a binary system, and would help explain why some vessels operated by the Colonials are so luxuriously equipped or outfitted for long duration flights, as it would most likely require vessels to make multiple jumps between stars, thus measuring journey times in terms of days (or possibly weeks).
• A star cluster might explain why the Colonials don't appear to have undertaken much in the way of really deep-space exploration. They might have been engaged in simply surveying other stars within the cluster , but at the same time being oblivious to the precise location of Kobol relative to their own worlds).
• A star cluster would give the Cylons ample opportunity to hide away from Colonial eyes, while still keeping a check on (and perhaps influence) Colonial activities.

Example of an Open Star Cluster

The Pleiades cluster is a classic exmaple of an open star cluster, although it is one that contains relatively young stars, many of which are burning too hot to sustain life-bearing planets.

Origin of the Name in the Original Series

In "The Long Patrol", Starbuck refers to the Twelve Colonies as being in the "Cyranus Galaxy". This may be an error on the part of the series writers on the grounds that:

• The Colonials are seeking Earth, and so must be travelling within the Milky Way Galaxy
• The Original Series neither shows nor implies any inter-galactic travel.

Counterpoints:

• Earth in the Original Series does not have to be the Earth of the Milky Way Galaxy.
• The Original Series may use a different name for our galaxy, so inter-galatic travel is not necessarily implied.
• The Original Series may use a different definition for the word galaxy to mean solar system or sector. There are several examples in the series that appear to bear this out.
  • The lead Centurion in The Hand of God orders their Raiders on patrol deeper into the galaxy.
  • The episode "Saga of a Star World" makes clear that a Raider needed to refuel to reach the Colonies from the Cylon Empire.