Navigating in Colonial Space
There are two forms of Astrogation used by Colonial ships. The first is the Cyrannus Centric Sidereal Astrogation System, commonly called the Colonial System or CS. The second is the Galactic Relative Astrogation System (GRAS) centered on the Galactic Core.
The Colonial System uses the Cyrannus System as its center. All reference points are made relative to an imaginary center of the Cyrannus system. This center point is marked by the first of a series of Navigational Beacons. These beacons, a total of 13, coupled with standard sidereal mapping and astrogation techniques, formed the framework of the Cyrannus Centric Sidereal Astrogation System.
Known Colonial Space, which was roughly spherical in shape, was at its widest point 34.6 light yahrens across. The center of this sphere, and area of highest density, was the Cyrannus System. Astronomically speaking, the Cyrannus system and the surrounding star systems, actually forms an Open Cluster.
The core of the sphere, an area approximately 1 light yahren in radius, was designated Alpha Sector (The navigation beacon in that sector is Alpha Prime. The other twelve beacons are known by the sector in which they were located. Beta Prime, Gamma Prime, Delta Prime, Epsilon Prime, Zeta Prime, Eta Prime, Nu Prime, Xi Prime, Omicron Prime, Lambda Prime, Mu Prime, Sigma Prime and Omega Prime. )
Moving outward from Alpha Sector, Colonial Space was divided into additional sectors that wrapped around the center like the layers of an onion. The sectors varied somewhat in size, generally becoming larger as they moved further from the center.
Alpha Sector was surrounded by the ‘Inner Layers.’ On one side by Beta Sector and on the other by Gamma.
The Inner Layers in turn gave way to the ‘Belt Sectors.’ Beta Sector to Delta and Epsilon while Gamma was bordered by Zeta and Eta.
Moving outward through the Belt Sectors a space ship would enter the ‘Middle Band.’ From Delta into Theta sector or Iota. From Epsilon the ship would reach Iota or Kappa sectors. From Zeta a ship entered Lambda, Mu or Nu. And from Eta either Nu, Xi or Omicron sectors.
The ‘Outer Sectors’ were Pi, Rho, Sigma and Tau, which were reached by passing outwards through Nu, Xi or Omicron. And Upsilon, Phi, Chi, Psi and Omega. Which lay beyond Lambda, Mu and Nu sectors.
The Navigation Beacons, combined with ‘Hallmark’ stars and natural phenomena that are plotted on star charts, provide the coordinate system to locate a ship and plot its course to a location anywhere inside Colonial Space or the areas immediately outside it. The Sector system is purely a navigational reference aid, it in no way represents any governmental or administrative division.
The Galactic Relative Astrogation System (GRAS) was adopted by the Colonial Military and some civilian ships, to facilitate astrogation outside the area of known space and to make it easier to cooperate with the Delphian Fleet in joint operations.
Galactic Relative employs a three dimensional plotting system that uses the intersection of the projected Galactic Core and the Galactic Plane as a reference point. The third dimension is based on the direction of spin to bisect the Galactic Plane.
Common reference numbers are given to three to five digits, to allow a general area to be located More accurate descriptions, such as to locate a star system on a chart, are given to seven to ten digits. Actual astrogation, requires coordinates of fifteen or more digits for safety and reliability.
The Fugitive Fleet uses the GRAS for operations.