Tuesday, December 10, 2013

My Little Star Catalog

Is the French Arm giving the American Arm the finger?
I remember really digging the original Traveller's subsector maps until I got to the Solomani supplement.  It became all too obvious that Traveller's space was two dimensional and just horribly, horrible wrong.  Of course, players never cared, but it bugged the heck out of me.

Star Frontiers wasn't any better, so I remapped THAT universe into 3D - just because.

Then Traveller: 2300 came out, containing a glorious map of the REAL local space.  Besides the map, it came with a distilled version of Gliese Near Star Catalog - version 2 - in a nifty little booklet.  I sat and mapped stars for days with that booklet, a pencil, and graph paper.  I loved it, and that booklet stayed with me much longer than the game ever did.

In the 90s, I found digitized versions of the Gliese Catalog and others - including the Yale Bright Star Catalog.  There was a very nifty BBS in North Texas back then run by amateur astronomers - and it was glorious.  There was a simple spreadsheet program in the Microsoft Works package, and I set about trying to map the galaxy.

Hipparchos parallax - accurate to ONLY 1600 light years.
Running the numbers, I realized Douglas Adams was right.  Space is fucking huge.  Light travels at a snail's pace.  And, for all their nifty telescopes and sciency shit, astronomers are just guessing at the distances of the stars.  BIG guesses.  Most of the stars that we can see are very, very local - in galactic terms.

A much more comprehensive survey came out - the Hipparcos Catalog.  It was so big my computer couldn't grok it.  I sighed and stepped away from star mapping for a while.

By the time I had regained my interest and could afford a faster computer, I ran into Winchell Chung's web page.  Beside's defining the look and feel of Steve Jackson's OGRE back in the mid 1970s, Winchell Chung is also a star mapping freak of the highest caliber. He's got so much about star mapping on his site - it boggles the mind.  Because of his work in this field, he remains one of my favorite people in the universe - even though I've never communicated with him.  Talk about stalky. :)

So much of the work was already done for me on the site that, well, I got lazy.  Any time I'd want to know information - distances - whatnot - I'd just hit the site.  But this year - after delving back into GURPS, I got hungry for star mapping again - BIG star mapping.  It dawned on me that I have been doing database work as a career for almost 20 years now, slicing and dicing huge wads of data in the blink of an eye.  The stellar data, by comparison to bank transactions, is relatively small.  So I pulled in the data and it was glorious fun.

I present to you, without further ado, the Arkhein Derived Catalog (Simplified.)  Please note, this data is not accurate enough for astrogation purposes.  Black holes are not charted.  Your mileage may vary.

ArkheinDerivedCatalogSimplified.csv contains 18,729 star systems within a 135 parsec cube centered on Sol.  It is derived from The HYG Database (a dataset derived from Hipparcos, Yale, and Gliese,) the HabCat Dataset (from Jill Tarter and Margaret Turnbull - a list of systems that might contain a habitable planet) and data from the NASA Exoplanet Archive as of September 22, 2013.

This simplified version I'm putting out for public comsumption is rather slim - with the following columns:

ADCID Arkhein Catalog Derived ID # for my own tracking.
HIP The Hipparcos Catalog Number.
CommonName Of all the names of the system, my own, personal favorite.
Distance In parsecs from Sol.
AbsMag A sciencey brightness thingy.
Spectrum The Hertzsprung-Russell classification.
ColorIndex A sceincey color thingy.
Xg Cartesian coordinates based on a Galactic orientation.
Yg Cartesian coordinates based on a Galactic orientation.
Zg Cartesian coordinates based on a Galactic orientation.
HAB SETI watch candidae per Tarter/Turnbull.
pl_hostname System name per NASA Exoplanet Archive.
pl_pnum Number of verified exoplanets, per NASA.

Part of the reasoning behind the cubic shape of the data is to organize the stars into cubes.  Though not in the simplified dataset, I have everything in this 135 parsec wide cube sliced up, identified, and named.  I may publicize this later, as I tried to make it as neutral as possible, naming each unit after the brightest star in the area.

The hierarchy is as follows:

Width (parsecs) Cubic Parsecs Comprised of . . .
Subsector 5 125
Sector 15 3375 27 Subsectors
Region 45 91125 27 Sectors

Thus, the 135 parsec area is made up of 27 Regions, 729 Sectors, and 19,683 Subsectors.  A huge amount of space, yes, but easily slice and diced with a database.

The naming convention of the areas results in Sol being located in . . .

Subsector: Sirius
Sector: Vega
Region: Aldebaran

. . . which seems pretty neat to me.

I've got some ad hoc calculations to randomly (but logically) determine human habitable systems from all of this data.  I get about 520 planets with complex life on them out of the entire area.  A lot more planets with single cell life, but those are far less interesting. :)

So there it is - my life's work.  Yay.  It will all go toward a GURPS: Space campaign one day.  Please let me know if you have any questions or are interested in seeing any of the additional data.

- Ark


  1. Awesome. I made a map of the stars in a panoramic view in drafting class back in 85 or 86 based on a star catalog in an astronomy book from my school library no on else had checked out for 20 years. The catalog for Traveller:2300 tickled me pink.

  2. This is fantastic!

    Got to admit, the 2D map never really bothered me. For my Traveller campaign, I mapped a standard Traveller Sector in another (tiny compared to the milky way) galaxy. I've been contemplating mapping the entire galaxy, which, as you say, point out, isn't really all that difficult with today's IT. I'd let that project slide, as I haven't run that campaign since June... but between my players asking about it, and your work here, I think I've got the bug back both for my game and my galaxy project!

  3. I just assumed that the Traveller maps were maps of how the star systems related to each other via Jumpspace rather actual space. Therefore, a flat map made perfect sense. Problem solved.

  4. Very cool, and good on you for doing the work.

    I do agree with Erin though, flat maps can make sense if they are 2d jump space distances, rather than any relationship to 3d space.

  5. Love it. Curious, why Aldebaran:Vega:Sirius? I would have though you would have pulled a star trek, and labelled it 0:0:0; or Sol all the way down.

  6. Winchell is a daily presence in the G+ Traveller communities.