Is there a 'north' on a star chart?

Rincewind

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Please can somebody advise me about this?

I'm playing around, writing SciFi stories, and it's occurred to me that I've been using star charts as if they're basically the same as terrestrial maps.

So, for example, I'd explain that this star system is west of another star system.

Is this the correct way to describe this positioning?

Thanks.
 
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Would help to have some more information about how the maps are being used. An astronomer on Earth using a star map to find a star in the sky would definitely have north/south East/West distinctions. If it is the Captain of the Enterprise charting a warp jump that could be completely different. North and South might translate to opposite sides of the disk of the galaxy. East and West don't translate so well. You'd probably have clockwise/counterclockwise instead. Also a radial distance from the galactic center would make sense on such a star chart.
 
Thanks!

I'm using it to describe to the reader the relative positions of various star empires/kingdoms/etc. If I ever publish, the book will have a map included, so I'm helping the reader find things!

So, it seems that N/S/E/W are suitable.

Actually, I'm enjoying the research immensely, so I'm unsure if I'll every produce any books! It's more something to keep the brain exercised after retirement!

Thanks again!
 
Rincewind said:
Thanks!

Similar to Discworld!
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It would really depend on the size of the area that you're dealing with. The Inner Sphere is only about 1000 light years in diameter, so toward or away from the galactic core and with or against the galactic spin work on their maps. If you're filling a significant portion of a galaxy, that obviously won't work, since they could be opposite directions.
 
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Armitage72 said:
It would really depend on the size of the area that you're dealing with. The Inner Sphere is only about 1000 light years in diameter, so toward or away from the galactic core and with or against the galactic spin work on their maps. If you're filling a significant portion of a galaxy, that obviously won't work, since they could be opposite directions.
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In one of the stories the area is around 300 x 300 x 50 light years. Effectively part of an arm of a spiral galaxy.

So maybe the spin isn't a factor as I'd assume the whole arm is spinning at the same rate as the whole galaxy.

Within the boundaries of my 'sector' I'm also assuming that everything is relatively static.
 
Rincewind said:
Please can somebody advise me about this?

I'm playing around, writing SciFi stories, and it's occurred to me that I've been using star charts as if they're basically the same as terrestrial maps.

So, for example, I'd explain that this star system is west of another star system.

Is this the correct way to describe this positioning?

Thanks.
Click to expand...

Well for one you need three axes in space.
 
Are you pretending (as most galactic-scale space empire SF does) that everything important is spread out on one plane? There are good reasons for doing that; it's really hard to depict three dimensional star maps on a page, for instance. And you can defend your borders with a ring of outposts, instead of needing a whole sphere of them. (Provided your enemies are honorable and won't cravenly exploit the third dimension.)

The reason spinward/antispinward makes sense as a navigation axis in deep intragalactic space is that, after coreward/rimward, it's the second easiest axis to align yourself on by observation. If you can find the galactic core you've got coreward/rimward, and if you can find the galactic disk and figure out which side of it is "up" you can move at some angle from coreward or rimward that keeps you in the main plane. It's not because the galactic rotation itself is important to navigation.
 
Myriad said:
Are you pretending (as most galactic-scale space empire SF does) that everything important is spread out on one plane? There are good reasons for doing that; it's really hard to depict three dimensional star maps on a page, for instance. And you can defend your borders with a ring of outposts, instead of needing a whole sphere of them. (Provided your enemies are honorable and won't cravenly exploit the third dimension.)

..snip...
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The Z axis is important in the real world, but, as you say, difficult to depict on a printed page. Also most people aren't used to thinking in three dimensions. This was used as a plot point in Wrath of Khan. Khan being a land general thought ony in X & Y maneuvering.
 
Thanks to all of you - plenty of ideas!

I do have a "Z' axis built in - the approximate dimensions of my chunk of space is 300 x 300 x 50 LY - it's flattened like as part of a typical spiral galaxy. So - the 'Z' axis is less important!

And I haven't forgotten the Wrath of Khan - great plot device!

I have spent a lot of time working on populations and what people do as well as armed forces organizations and hardware and building spreadsheet to get Excel to do all the calculations, and only recently moved onto creating star systems. In Excel, of course!
 
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I've learned something else from the "theory of relativity" thread - whereas there's a possibility of using North/South in a galactic context, East and West have no place.

So - it's good to be eddikated!!!
 
Rincewind said:
I've learned something else from the "theory of relativity" thread - whereas there's a possibility of using North/South in a galactic context, East and West have no place.

So - it's good to be eddikated!!!
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You of all members, should really be familiar with the terms "hubwards",. "rimwards", "turnwise" and "widdershins".
 
Traveller uses "coreward", "rimward", "spinward", and "trailing". To handle all three dimensions, you just need to define an "up" and "down", perhaps using the positive and negative pole definitions in Wikipedia's article on the pole of astronomical bodies.
For intragalactic coordinates, you could define a zero meridian (perhaps through the capital planet's star), then refer to a location by degrees/grads/radians CCW from meridian, distance from center, and distance above/below the equator of the galaxy.
For intergalactic coordinates, perhaps a polar coordinate from some important planet, as we use Right Ascension, declination, and distance.
 
SkepticScott said:
For intragalactic coordinates, you could define a zero meridian (perhaps through the capital planet's star), then refer to a location by degrees/grads/radians CCW from meridian, distance from center, and distance above/below the equator of the galaxy.
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I remember the Third Doctor saying that Gallifrey was located at "10, 0, 11, 0, 0 by 0, 2 from galactic zero center", but it was obviously just technobabble.
 
Rincewind said:
I've learned something else from the "theory of relativity" thread - whereas there's a possibility of using North/South in a galactic context, East and West have no place.
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So do you plan to define North as antiparallel and South as parallel to the direction of Anisotropic Dark Flow Acceleration?

Dave
 
If you're writing sci-fi why not invent something new? Term all directions as colors and never explain how it works because all the characters understand it so they never even think about it. The Sex Planet is yellowwards of the Llama Confederation, which is bluegreenish of the Empire of Doom and Waffle Fries, rendering the entire red side of the galaxy inhospitable to any cyborg nannies trying to make it big in show business even if they inherited those emerald mines on the Sapphire Planet from their Great Uncle Borg.
 
Armitage72 said:
It would really depend on the size of the area that you're dealing with. The Inner Sphere is only about 1000 light years in diameter, so toward or away from the galactic core and with or against the galactic spin work on their maps. If you're filling a significant portion of a galaxy, that obviously won't work, since they could be opposite directions.
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East in New York City is opposite of East in Beijing. You don't think of it that way because you're used to it, and your mind automatically "unrolls" the earth, but it's still true. And "Clockwise" at 12 is opposite of "Clockwise" at 6, but you're used to thinking of it as a circle. Same thing on a galactic scale: you're using a polar coordinate, but that's really not a problem, especially if the people using it will use it a lot.
 
TragicMonkey said:
If you're writing sci-fi why not invent something new? Term all directions as colors and never explain how it works because all the characters understand it so they never even think about it. The Sex Planet is yellowwards of the Llama Confederation, which is bluegreenish of the Empire of Doom and Waffle Fries, rendering the entire red side of the galaxy inhospitable to any cyborg nannies trying to make it big in show business even if they inherited those emerald mines on the Sapphire Planet from their Great Uncle Borg.
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Alternatively, make up an alien alphabet of about 30-40 letters, assign a six-letter code to each planet according to an obscure mapping to a 3-D co-ordinate scheme, then suggest that the resolution of this coding system is fine enough that the relative movements of stars over timescales of a few months makes significant differences to it.

Ooops, no, sorry. That one's taken.

Dave
 
Dave Rogers said:
Alternatively, make up an alien alphabet of about 30-40 letters, assign a six-letter code to each planet according to an obscure mapping to a 3-D co-ordinate scheme, then suggest that the resolution of this coding system is fine enough that the relative movements of stars over timescales of a few months makes significant differences to it.

Ooops, no, sorry. That one's taken.

Dave
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Everything in that franchise is super realistic and believable in comparison to the notion that the US military would allow an officer to sport a bed-head hairstyle while in uniform. All the magical aliens and nonsense science are as nothing compared to that insanity.
 
TragicMonkey said:
If you're writing sci-fi why not invent something new? Term all directions as colors and never explain how it works because all the characters understand it so they never even think about it. The Sex Planet is yellowwards of the Llama Confederation, which is bluegreenish of the Empire of Doom and Waffle Fries, rendering the entire red side of the galaxy inhospitable to any cyborg nannies trying to make it big in show business even if they inherited those emerald mines on the Sapphire Planet from their Great Uncle Borg.
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Are those the Emerald mines that the TragicMonkey consortium took over in a hostile bid to gain a monopoly?
 
Rincewind said:
Are those the Emerald mines that the TragicMonkey consortium took over in a hostile bid to gain a monopoly?
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The TragicMonkey Continuum would never be hostile to miners. If anything we're extremely fond of miners, big muscular sweating miners.
 
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