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croiduire:refuge:space:navigation

Navigation

Astral navigation, the art or science of plotting, ascertaining, and directing the course of a spellship, is one of the biggest challenges facing spacefarers. Distances, both between and within spheres, are vast, the speeds at which they travel are extreme, which leaves little margin for error, and the dangers are many and frequently deadly. To even these formidable odds, astromancers, sages and starsailors have honed several tools, techniques and spells.

The oldest, and most widely used, method is Positional Navigation, a position-fixing technique that uses angular measurements (sights) between landmark astral objects and the galactic plane of the ecliptic. Skilled navigators rely on the numerous navigational stars whose coordinates are tabulated in the CDN almanacs. In addition to the vital almanacs, positional navigation requires a reliable chronometer or chronomantic spell to precisely determine time, a sextant to measure the angles, a set of correlation and conversion tables…and a keen mathematical mind.

Any direction can serve as the plane of reference, as long as it is clearly defined for everyone using the system. All certified navigational tools in Known Space are sorcerously calibrated to share the same plane of reference. Celestial North, also called the Prime Direction, is the geospheric North of Arvandor; the artificial bubble horizons of sextants and octants correspond with the plane of the ecliptic that spreads out from the orbit of Arvandor, and permit the complex geometric computation to determine a ship's azimuth and bearing.

More accurate, but more demanding of the navigator, is Dead Reckoning, the process of ascertaining the ship's current position based upon a previously established position. This is done through a combination of instrumentation and arcanology. Gyroscopes detect rotation, and sensitive spring-driven accelerometers reveal the slightest change in motion relative to freefall, while a series of Illusion and Divination spells are used to calculate changes in the ship's position, orientation, and velocity. This information is then logged and tracked relative to the previous coordinates and the desired heading. With this detailed information a course can be calculated with exceptional exactitude, but even the most exact course and skilful crew cannot guarantee an uneventful flight through, and between, Spheres.

Boxing the Compass

Compass point Abbreviation
North N
North by east NbE
North-northeast NNE
Northeast by north NEbN
Northeast NE
Northeast by east NEbE
East-northeast ENE
East by north EbN
East E
East by south EbS
East-southeast ESE
Southeast by east SEbE
Southeast SE
Southeast by south SEbS
South-southeast SSE
South by east SbE
South S
South by west SbW
South-southwest SSW
Southwest by south SWbS
Southwest SW
Southwest by west SWbW
West-southwest WSW
West by south WbS
West W
West by north WbN
West-northwest WNW
Northwest by west NWbW
Northwest NW
Northwest by north NWbN
North-northwest NNW
North by west NbW

The sailmaster mate (also known as the quartermaster or signaller) is an enlisted member assigned to the Sail department in charge of facilitating and implementing watch-to-watch navigation and keeping the astronautical charts current under the direct supervision and control of the ship's sailmaster (navigator). He is also responsible for the care and maintenance of the ship's chronometer and other timepieces, of the navigational and signalling equipment and instruments, and for training of ship's lookouts. The authorisations to take readings is a grey area: it is usually not permitted on larger ships, but is frequently unavoidable on smaller ships with only a single navigator.

The Imirie has six ratings assigned to the Sail department: three sailmaster mates and three lookouts, one of each for all three watches.

croiduire/refuge/space/navigation.txt · Last modified: 2015/01/08 14:41 by Croi Duire