Interstellar navigation represents the future of spatial travel in the cosmos, made viable by advancements in understanding the complexities of the universe. Unlocking the vast potential of the galaxy, it facilitates navigation on a wide scale and revolutionises the conventional terrestrial concepts of direction.

The traditional notions of North, South, East, and West become insufficient when transposed upon the vast, three-dimensional canvas of the galaxy. The challenge of interstellar navigation necessitates a system that could describe any location within this unbounded expanse.

Ascension, Declination, and Radius

At the heart of interstellar navigation are three linear coordinates: Ascension, Declination, and Radius. These distinctive measures, reappropriated from ancient astronomical terms, have been redefined to serve the needs of galaxy-wide travel.

Ascension (Asc/A) replaces traditional longitudinal measurements, indicating the horizontal direction of a point in the galaxy relative to the Galactic Core, the pulsating anchor amidst the cosmic sea. It is commonly measured in

• Degrees (Aº ranging from 0 to 360)
• Arc-hours (*, 1/10 of 1º)
• Arc-minutes (', 1/100 of 1*) and
• Arc-seconds (", 1/100 of 1').

Further precision is acquired through decimal Arc-seconds.

In layman's terms, we pick a direction - like the hand of a clock - in which we point to find our destination - but instead of a clock, which is two-dimensional, we point with a semicircle instead. Now we need to point to a direction along that semicircle.

Declination (Dec/D) offers a substitute for latitudinal measurements, showing the vertical alignment of a point with reference to the galaxy’s Planar Middle, an imaginary equatorial plane bisecting the galaxy. It is commonly measured in

• Degrees (Dº - ranging from -90 to 90)
• Arc-hours (*, 1/10 of 1º)
• Arc-minutes (', 1/100 of 1*) and
• Arc-seconds (", 1/100 of 1').

Further precision is acquired through decimal Arc-seconds.

Using Ascension and Declination from the galactic core, we have constructed an imaginary ray. Asc and Dec determine where it points - now it just needs to stop at a destination.

Radius (Rad/R) outlines the distance from the Galactic Core to any specific location. This is measured in

• Core Radii (Cr or kPc)
• Parallaxes (Parsec/Pc, 1/1000 of 1 Cr)
• Milliparallaxes (mPc, 1/1000 of 1 Pc)
• Microparallaxes (µPc, 1/1000 of 1 mPc)
• Nanoparallaxes (nPc, 1/1000 of 1 µPc)

delimited by apostrophes with trailing zeroes omitted ('). One nPc is approximately 31000 Kilometres.

Interstellar Coordinates

The correct format for interstellar coordinates is A(Unit)D(Unit)R(Unit). Some examples include:

Navareo - A(228º5*22'99")D(3º0*11'41")R(1'272'997)
Tallis - A(265º8*71'03")D(-17º4*53'20")R(7'615'106)
Galathea Station - A(165º2*41'87")D(56º1*72'97")R(0'000'087'211)

Interstellar Directions

To encapsulate each of the six directions in this coordinate system succinctly, each movement in Ascension, Declination and Radius has its own shorthand: Spinward and Trailward (Ascension), Zenithward and Nadirward (Declination), and Coreward and Rimward (Radius).

• Spinward (Sw/A+) implies movement in the direction of the galaxy’s rotation, leading to an increase in Ascension.
• Trailward (Tw/A-), the reverse of Spinward, signifies traversing against the direction of the galaxy’s rotation, hence decreasing in Ascension.
• Zenithward (Zw/D+) determines ascension above the galactic plane, an increase in Declination.
• Nadirward (Nw/D-), refers to descent below the galactic plane, a decrease in Declination.
• Rimward (Rw/R+) refers to movement away from the Galactic Core, increasing in Radius.
• Coreward (Cw/R-) denotes movement towards the Galactic Core, decreasing in Radius.