Navigational Directions in space

[Zor]

This is a minor background thing, but here are my thoughts in regards to this

Often in science fiction, people make intersteller maps with North South East and West as navigational directions (Battletech, Warhammer 40,000 being notable commiters of this crime) and i think that this is a rather daft way of doing things. These directions were developed as a means of navigating on the effectively 2-D surface of a planet and just don't work in a three dimentional setting.

For my own fictional universe i have decided to come up with my own system of navigational directions

Corewards: Towards the Core of the Milky way Galaxy

-Rimwards: Away from the core of the Milky Way Galaxy

-Turnwise: in the direction in which the spiral arms of the Milky Way galaxy spins outward

-Counter Turnwise: in the direction in which the spiral arms of the Milky Way galaxy turns inward

-Plain: If one was to take the galaxy and cut it horizontally through the center, it would be divided into two plains, the Alpha Plain and the Beta Plain, the Alpha plain being defined as the plain in which Sol is located. Alphaward being considered “up”.

-Alphaward: Towards the ‘Top’ of the Alpha Plain

-Betaward: Towards the ‘Bottom’ of the Beta Plain

Has anyone else done the same when writing fiction?

Zor

[Stark]

Wow, you 'came up with' a method of direction used since the 50s! You're a savant!

Except 'spinward' is way less dumb-sounding than 'turnwise'.

[Vehrec]

The dividing the galaxy into two planes is interesting-finally a Z-axis that makes sense.

Stark, Terry Pratchett uses turnwise to describe directions on Discworld. If it's good enough for Sir Terry, it's good enough for me.

[Isolder74]

Well in the story i am writing i uses bearings based on the galactic plane and a line drawn from Earth to the Galactic center.

I do use north and south to at least cover above and below the plane made by that line or - and + whichever is easier to picture. I haven't quite worked the system out completely but it is a radial coordinent system.

[Stark]

The dividing the galaxy into two planes is interesting-finally a Z-axis that makes sense.

Two planes = z-axis? You still need a unit measure and that is going to be the axis; this plane nonsense is just a general direction thing.

Stark, Terry Pratchett uses turnwise to describe directions on Discworld. If it's good enough for Sir Terry, it's good enough for me.

A) Prattchet sucks and suggest him using something means it can't be 'dumb sounding' means you're an idiot
B) upspin/downspin is massively old and thus Zor just reinvented the wheel becasue he's never read a book

[Zor]

Terry Pratchett uses turnwise to describe directions on Discworld. If it's good enough for Sir Terry, it's good enough for me.

I fully admit that is where i got the term from. It just seems to make sense.

Zor

[Stark]

So you even admit the system you 'came up with' you just stole from Pratchett who used it as a generation of scifi writers already had? Hilarious.

[phred]

Assuming I'm reading Isolder's description correctly, it seems like a logical way to map the galaxy.

- Put grid locations with the core as 0 and measured out from there. (Hundreds of lightyears? thousands?)
- Use + - to measure north and south from where you are from the galactic plane. (See above)
- Use a line from the core to the sun as a 0 point and measure degrees around the galaxy.

Prattchet sucks

Blasphemer!! And you misspelled his name.

Seriously, you sound extra pissy today. Do you need a hug?

[Zor]

So you even admit the system you 'came up with' you just stole from Pratchett who used it as a generation of scifi writers already had? Hilarious.

Yes, most writers admit that not every single fucking thing in their fiction is their own independant spontaious creation. I just re-applied an established idea for a navigational direction from a two dimentional area to a three dimentional one.

Zor

[Samuel]

Seriously, you sound extra pissy today. Do you need a hug?

C:\Users\Michael\Desktop\Lets_hug_Nidhi_ratish_by_FrealaF.gif

I should note you could just use a starting star and two other stars with degrees off the line in order to give directions. Unless there is something in interstellar space you want, you don't need to map it.

[Stark]

Assuming I'm reading Isolder's description correctly, it seems like a logical way to map the galaxy.

- Put grid locations with the core as 0 and measured out from there. (Hundreds of lightyears? thousands?)
- Use + - to measure north and south from where you are from the galactic plane. (See above)
- Use a line from the core to the sun as a 0 point and measure degrees around the galaxy.

All the jiggery-pokery people engage in is just to have 'traditional' square maps rather than arcing ones (which you'd get in these situations). For instance, if treaties defined boundarys as they do these days, over a long enough distance they'd be curved, and some people go to great lengths to avoid this.

Blasphemer!! And you misspelled his name.

Seriously, you sound extra pissy today. Do you need a hug?

Sorry when people claim to have 'come up with' something that's OLDER THAN MY DAD I think it's funny as hell.

I mean, claiming to have invented up/downspin, in/outward? It's so ludicrous.

[Hawkwings]

What's wrong with north/south/east/west? Draw a line from the center of the galaxy to some important bearing (through your home system, perhaps) and call that direction galactic "North". Then base the rest of the coordinates off that. As for the z-axis, make the plane parallel to the equatorial plane of the galaxy, and have 0 on the z-axis be the plane that your home system is in. Coordinates for the Sol system would then be "bearing 000, distance 28,000LY, Z +0LY". Some random place might be "bearing 276, distance 8,000 LY, Z -300LY".

Of course, all coordinates would shift slightly due to the rotation of the galaxy and whatnot, but that happens on such a long timescale that you only really need to update the maps once in a generation or so if you were really anal about it.

[Zor]

I mean, claiming to have invented up/downspin, in/outward? It's so ludicrous.

Did i claim that i was the first to come up with it? No. I was just wondering if...

A-People shared my opinion that using North South East and West as space navigation directions is a silly idea that should not be done
B-If anyone had come up with their own system for it.

Zor

[Isolder74]

Assuming I'm reading Isolder's description correctly, it seems like a logical way to map the galaxy.

- Put grid locations with the core as 0 and measured out from there. (Hundreds of lightyears? thousands?)
- Use + - to measure north and south from where you are from the galactic plane. (See above)
- Use a line from the core to the sun as a 0 point and measure degrees around the galaxy.

Yep that's my system. the Units I use for the distance from the earth circle are parsecs. - inward towards the core + outwards from the earth circle.

[Count Chocula]

Generally speaking, I've read three major non-planetary referents that make sense to me. They are:

1. Set the galactic core as 0,0,0 and measure outwards from there for planetary locations using x, y and z axes, with the z axis divided into + and - based on the plane of the ecliptic. This accomplishes the goal of subdividing sections of a galaxy, but does not take into account the motions of the galactic arms (assuming a spiral or barred galaxy), perturbations within those arms from supernovae, black holes, and the like, or the motion of a planet around its primary or primaries. This raises lots of complications in navigation that can be taken advantage of in fiction. IIRC, Heinlein's earlier fiction included starships dropping from FTL back to normal space to take astrographic location readings based on their location, with appropriate corrections and atlas lookups. I'm thinking specifically of Starman Jones.

2. In-system coordinates based on references from the system primary (or the center of gravity in a binary system), again with the plane of the ecliptic determining + and - z assignments. IIRC, Larry Niven used this system in his Known Space series, but I could be wrong...it's been a while since I read any Puppeteer novels.

3. Single-ship motion, intrasystem or intersystem, based on the ship's or fleet's vector (typically measured from the bow, under acceleration). Referring to motion from the velocity vector of the ship allows for tactical maneuvers, and also allows calculations based on (2) above for "short" interstellar trips or (1) for longer trips, such as the one Amidala & Co. made from Tatooine to Coruscant.

Zor's referents are valid, to be sure, but they all seem to assume a larger coordinate set that he hasn't stipulated.

[Junghalli]

1. Set the galactic core as 0,0,0 and measure outwards from there for planetary locations using x, y and z axes, with the z axis divided into + and - based on the plane of the ecliptic.

Another possibility: same deal but with your home sun as 0,0,0.

[Count Chocula]

^ Agreed, on re-reading the thread I realized I'd neglected the local referent. This could, of course, introduce all sorts of amusing episodes in a first contact scenario.

Human explorer: "Greeetings, Alien! I am Shep, exiled from Earth, Galactic Sector 0,0,0!"
Alien merchant: "Where the fuck is that, alien?"
Human explorer: "Why, it's right here (shows galactic map centered on Earth). And we have LOTS of nukes!"
Alien merchant (trying not to laugh): "Wow, your location way out on a minor cluster of a spiral arm of our galaxy is '0,0,0'! I better update my charts! And what's with the nukes, anyway? Your ship's way too small to be a mining operation."

Hilarity and gunshots ensue...

[Oskuro]

Prattchet sucks

Does your heart know no joy?

Anyway, why define Earth as (0,0,0) when there's a perfectly fine Galactic Center to define as such? My attempts at defining a navigation/coordinate system always come face first into the same problem: Points of reference. Since the whole thing is moving in space, it's hard to say what's where.
For example, one early idea I had (like eons ago) was to use the Galaxy as a Universal clock, defining dates, or even time, based on its rotation. Of course, it all came crashing down when I realized that it needed a starting point (t=0), a constant reference point to measure time increments, and also that Galactic rotations would probably be useless as a timekeeping method given our perception of time.

As for coordinates, if we were to define them through a radius/angle pair from the center, there would always be the problem of defining where 0º lies at. You can use some known feature, such as Earth, for that, but that wouldn't make the system Universal.

*checks Wikipedia*

Ok, so the Galactic center is, apparently, elongated. That makes things easier, as you can use the elongation as a line to divide the Galaxy in two sectors, still, there needs to be a point of reference to differentiate them. Maybe a Galactic arm could be used for that, for example the so-called Outer arm. If both ends of the Galactic center elongation can be differentiated this way, it's just a matter of labelling them something like, I don't know, + & - sides of the coordinate axis.

Oh well, enough speculation and re-inventing of the wheel, here are the Wikilinks I've used:

Milky Way
Galactic Coordinate System
Supergalactic Coordinate System

[Vendetta]

Does your heart know no joy?

Stark's only joy comes from the cathartic exercise of his own bile.

[TheLostVikings]

Anyway, why define Earth as (0,0,0) when there's a perfectly fine Galactic Center to define as such? My attempts at defining a navigation/coordinate system always come face first into the same problem: Points of reference. Since the whole thing is moving in space, it's hard to say what's where.

While on the topic of avoiding re-inventing the wheel, some smart guy realized you could use the extremely predictable output of millisecond pulsars as galactic reference points in the same way GPS uses satellites. (read: summary, Original)

His proposed system only uses 4 pulsars, so it would only be usable in this part of the milky way, but obviously the concept could easily be expanded. And since millisecond pulsars fitting for this purpose surely aren't evenly distributed across the different arms of our galaxy, you could most likely build a decent "reference map", to pinpoint your general location.

Of course stuff at different distances to the galactic core orbits it at different speeds, meaning you have to continuously update your database of reference point pulsars, but for an space faring civilization advanced enough to zoom around the galaxy this doesn't seem like an insurmountable problem.

As for the naming conventions I personally find most "new" naming schemes to be unnecessarily clunky, north/south/east/west are all relatively short words. And there is a good reason for that. While some terms like pre/despin, spinwards, etc sounds nice, they are simply too long to fit smoothly into a conversation. (all imho of course)

Probably the reason why the International Astronomical Union decided to repurpose the terms when creating their nomenclature. West being "spinwards" with East being the opposite direction to the direction of spin. North and South being defined as similar to earth based on the direction of spin on the object (i.e. Venus is "upside down" since it counter-rotates compared to earth). Add to that In/Out as how far something is away from the galactic core compared to your own location and you have a fairly comprehensive set of terms to describe relative location. (Out would be the generally used term to measure distance from the core, while In would refer to objects closer in than yourself. And maybe distance from the outer rim as well, though that seems harder to define well)

Leaving you with three sets of coordinates: N/S, E/W, (I/)O. If we're talking about a system used not only by humans the zero point for the E/W coordinates seems like it would be a hotly contested issue, but that more of a political issue than an actual problem with the system itself. (With the actual coordinates being defined by the "reference map" of known pulsars, you could always just draw an arbitrary line somewhere, though I bet none of the civilizations involved would agree to that )

[loomer]

I can only see it being of use to calculate some kind of FTL travel coordinates, but localized (parsec, say, based around a local black hole/nebula/whatever notable object, or even just the biggest thing in said parsec) would probably work better.

My sci-fi uses the same standards as the IAU on a local basis, but for relativistic travel they utilize Galactic Core coords adjusted for the travel of the destination. This is incredibly rare, though, as there are only really three types of ship to use such - initial explorers, normally people who live for literal centuries through cyrogenics and time dilation (one of them is still around from 2076, since he was one of the very first launched and has been exploring incredibly distant stars for habitable worlds), the FTL-Gate builder ships (Cliched, I know.) and the remnants of old nations and defeated powers who sent out feelers or 'seed' ships to far off planets, either before FTL was commonly available or to ensure that their chosen culture would survive on the other side of the galaxy.

That's pretty much the only reason I can see widescale use of a GCS, or even small scale.

[Nyrath]

Just to add some chaos to this confusion, the last I heard was that Sol was a mere 50 light years "north" of the galactic plane. Which ain't much when the thickness of the galactic arms in our galaxy are on the order of 1,000 light years.

RE: "north and south". In many fields, such as electromagnetism, they use the so-called "right hand grip rule." So using this incredible slight on lefties and south hemispherians, if you curved the fingers of your right hand in the direction of galactic spin, your right hand thumb will point north.

Trying to explain this system to an alien race who have only tentacles is an exercise for the reader.

[Junghalli]

Anyway, why define Earth as (0,0,0) when there's a perfectly fine Galactic Center to define as such?

Unless you have super-FTL your home system might make a slightly less clunky thing to use as your center than the far distant galactic core. If you use the galactic core you'll have to add a whole bunch of essentially unnecessary zeroes to at least one dimension, because every destination you're likely to go is ~30,000 light years to one side of the 0,0,0 coordinate. That might be a slight bit of a pain if the average journey is only a few dozen or hundred light years.

Plus ethnocentrism. It comes naturally to people.

[Batman]

The word is 'plane', not 'plain'.
Anyway:
What's the point of a galactic coordinate system? Why would you use it?
Supposing you are using it, how much time are you going to spend listing decimals? "He's at somewhere within a light year radius of galactic position 0, 0, 0.00004!" - The galaxy is so big, this system isn't likely to be precise enough to be terribly useful. It'll just be clunky to use.

So what kind of OTHER coordinate system would you be using if you were to have ships travel from one part of the galaxy to the other, preferably arriving in the system they were aiming at?

[Batman]

Again, nevermind.