The Solomani Sphere - in 3D?

[Frankymole]

I'm trying to work up a 3D version of real space using Traveller rules to generate the actual contents of the systems.

The main problem is finding a decent set of stellar data for known (as of today!) star locations. Most astronomical texts only give Right Ascension and Declination, ecliptic coordinates, and don't include distances. Even where distances are given, this still doesn't make for very satisfactory mapping using Traveller's traditional Coreward, Spinward etc alignment. For that, you need Galactic Co-ordinates.

Traveller:2300AD aka 2300AD has a great list of stars within 50ly but sadly uses the ecliptic system.

Does anyone know of a decent set of stellar data that uses Galactic Co-ordinates, and preferebly including the distance component? even better would be a map.

Then I can finally run the Solomani Sphere instead of the Solomani Circle.

 

[Malenfant]

Yes. Have a look at my Near Star mapping webpage

- should give you enough to get started... The maps there are a little out of date, apparently the RECONS list has been updated with some new stars and some distances have been refined.

I've got a spreadsheet there that converts from RA/Dec to galactic coordinates too that you may find useful.

I got a few other useful documents on stellar evolution and star generation on my Traveller webpage too.

 

[Frankymole]

That looks great - a beautiful piece of work. The Jump Drive/distance table assumptions are exactly the same as ones I used, for 3D subsectors based on the system given in White Dwarf decades ago. My subsectors are 8 x 9 x10 hexes, using an extra digit for the Z axis. So I like it!

The spreadsheet sounds tempting, I don't know where to get parallax data though and the stars Spica and Deneb (which will locate those sectors for me in 3D terms, and give clues to just where the Spinward Marches might roughly be!) are presumably too far away for parallax, I'm going to need to use distance estimates (which I have) in the calculation of direction for such far stars. I can probably just use trig to work out the incredibly small equivalent parallax!

 

[Frankymole]

PS the Traveller 2300AD 3D starmap has roughly 750 systems within 50ly (about 16pc), so I guess they missed loads (of dim M-types?) out?

 

[kaladorn]

You're a useful resource, Evil Dr.

Now, one question about the 2300 starmap: Did it not include some 'intentional' errors? (ie the kind that, if someone stole your stardata, would be identifiable after the fact in court?)

You might also want to look for Winchell Chung's homepage on stellar cartography (Nyrath the Indispensable or Nyrath the Nearly Wise).

http://www.projectrho.com/starmap.html

 

[Malenfant]

Originally posted by Frankymole:
The spreadsheet sounds tempting, I don't know where to get parallax data though and the stars Spica and Deneb (which will locate those sectors for me in 3D terms, and give clues to just where the Spinward Marches might roughly be!) are presumably too far away for parallax, I'm going to need to use distance estimates (which I have) in the calculation of direction for such far stars. I can probably just use trig to work out the incredibly small equivalent parallax!

I provide some links in Secton 1 of that mapping page for getting the star parallaxes - best bet is the Hipparcos catalogue and the RECONS one for the closest stars. Parallax data does exist for stars like Spica and Deneb, though there are large errorbars.

Deneb should be at galactic lon/lat of:
lon: 84.28472789 lat: 1.99754711

Deneb's parallax (according to hipparcos) is 0.00101 arcsecs, which is a distance of 3227.72 ly, which works out to 990.10 pc, or x = 98.54, y =984.58, and z = 34.51 hexes using my co-ordinate system.


Spica should be at galactic lon/lat of:
lon: -43.8876673 lat: 50.84455445

Spica's parallax (according to hipparcos) is 0.01244 arcsecs, which is a distance of 262.06 ly, which works out to 80.39 pc, or x = 36.58, y =-35.19, and z = 62.33 hexes using my co-ordinate system.

It should be noted that their locations in reality do not agree at all with their positions on the Charted Space map.

 

[Frankymole]

Originally posted by Malenfant:
It should be noted that their locations in reality do not agree at all with their positions on the Charted Space map.

Oh yes, definitely aware of that. This is for my own variant 'MTU'

Thank you for the data! I love the maps and will start stringing together some H&E extended systems, using the real star data (and when we get beyond into new systems, your realistic stellar tables which I like the look of).

 

[Frankymole]

You may all be aware of this site anyway. But as a kind of eye-candy "Thank You", may I draw your attention to the bottom of the page for a 'real' Solomani Sphere... http://www.stellarium.com/html/what_is_a_stellarium_.html

Now to have one of these for the imperium would be lovely.... D

 

[Frankymole]

Originally posted by Malenfant:

Deneb should be at galactic lon/lat of:
lon: 84.28472789 lat: 1.99754711

Deneb's parallax (according to hipparcos) is 0.00101 arcsecs, which is a distance of 3227.72 ly, which works out to 990.10 pc, or x = 98.54, y =984.58, and z = 34.51 hexes using my co-ordinate system.

I am probably being terribly thick here, but how do I use the galactic lon/lat and distance into the hex xyz co-ordinates? I'm using your convert.xls sheet. Is there a function in the sheet to do this for me? (I know I'm lazy!)...

STOP PRESS scratch that, just found the cells. Doh. Now, which way is "plus" on the axes? I presume the coordinates increase trailing, coreward and "up" from plan view (galactic north)?

 

[Malenfant]

As you probably figured out, all you need to do is enter the RA and Dec and parallax in the cells with the blue text, and the spreadsheet automatically calculates things to produce the galactic latitude, longitude and X/Y/Z in parsecs (relative to Sol) in red text

.

I put the axes on the maps... +X is directly toward the core, +Y is to Spinward of Sol. +Z is "above" Sol if +X is toward the top of the map. (so -X is Rimward, -Y is Trailing, and -Z is "below" Sol)