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== Examples of headings ==
 
== Examples of headings ==
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* All of these headings are dependent on the heading of the star ship when the command was given, and are meaning less outside of this context.
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* Heading from the [[Bajoran system]] to the [[Klingon Empire]] was 327-mark-215. ({{DS9|Sons of Mogh}})
 
* Heading from the [[Bajoran system]] to the [[Klingon Empire]] was 327-mark-215. ({{DS9|Sons of Mogh}})
 
* Heading from [[Deep Space 9]] to the [[Cardassian Empire]] was 269-mark-032. ({{DS9|The Way of the Warrior}})
 
* Heading from [[Deep Space 9]] to the [[Cardassian Empire]] was 269-mark-032. ({{DS9|The Way of the Warrior}})

Revision as of 11:45, 23 November 2013

Galaxy helm station

The heading is programmed in at the helm control station

File:Astrogator.jpg

Heading could also be changed by manipulating the dial on the ship's astrogator

A heading was a common way to describe the direction of travel of a starship. Headings were programmed in at the ship's helm control using a combination of two 360-degree directions on planes that are at a right angles to one another, separated by the word "mark". (TNG: "Datalore")

Imagine the ship at the center of two circles marked in degrees, one horizontal, and one vertical. The "Zero" of the 'horizontal' component of the heading, termed the azimuth (the circle on the xy-plane) is a horizontal vector pointing directly in front of the ship, and the angle is measured counter clockwise from the positive x-axis, meaning a azimuth angle of 90 degrees corresponds to a heading pointing directly to the left (port) of the star ship. This angle is often denoted using the greek letter Theta.
The "Zero" of the 'vertical' component of the heading, termed the altitude or elevation (the circle on the xz-plane) is a vertical vector pointing directly up from the ship, and the angle is measured downwards from the positive z-axis, meaning an elevation angle of 90 degrees corresponds to a heading pointing directly in front of the starship, while an elevation angle of 180 points directly down. This angle is often denoted using the greek letter Phi.
In practice, the elevation angle is always bounded between 0 and 180 degrees, because an elevation angle outside of this range has the effect of reversing the direction of the horizontal heading from that would be intuitively expected from the given azimuth angle, in effect changing the 'horizontal heading' from that which was stated to an angle directly opposite, in effect adding/subtracting 180 degrees from the azimuth. While it is mathematically sound to allow this angle to vary outside of this range, it creates unnecessary confusion for humans visualizing the desired heading.
i.e. heading "0 mark 185" would actually point down and behind the ship, as opposed to down and infront of the ship as might be Naively expected.
The writers almost always ignore this fact, probably due to lack of mathematical understanding of the spherical coordinate system. (typically not encountered by most people until multivariate calculus) Capt Jack 4:28, 23 November 2013 (UTC)


The terms heading and course were often used as synonyms. (TNG: "Brothers"; TOS: "The Deadly Years", etc.) Starships traveling at warp speeds usually traveled in a straight line to the destination coordinates. (VOY: "Drive") While sometimes, a course could also be a more elaborate flight path, that included changes in heading and parabolic trajectories. (VOY: "Alice"; Star Trek II: The Wrath of Khan)

A more precise measuring angle system, beyond the 360-degree system, was sometimes used with headings such as 903-mark-6. (TOS: "Day of the Dove"; TAS: "The Practical Joker"; VOY: "Workforce")

Examples of headings

  • All of these headings are dependent on the heading of the star ship when the command was given, and are meaning less outside of this context.

Appendices

See also

Background information

The first use of headings in degrees occurred in Star Trek: The Original Series episode "Balance of Terror". The meaning of headings as two 360-degree angles was established in "Datalore". The system of degrees was further explained in reference books, such as Star Trek: The Next Generation Technical Manual (pgs. 36, 37).

The first 360-degree figure is a direction in an imaginary plane similar to the galactic plane, but between the ship and the center of the galaxy. What ever the location of the ship in the galaxy is, heading 000-mark-0 is always a direct course to the center of the galaxy. Heading 180-mark-0 is a direct heading away from it. A heading from Earth directly to the Beta Quadrant would be 090-mark-0 and further into the Alpha Quadrant 270-mark-0.

As explained in "Datalore", the second 360-degree figure is the elevation angle at a right angle to the previous plane. A heading of 000-mark-90 would be a heading directly upwards away from the plane, where as 000-mark-270 a heading directly downwards.

External link