Historical Datasets

Historical databases should not be considered “accurate” by modern standards, and have been largely superseded by the ones listed in the “Accurate Datasets” section. The full Yale and Gliese catalogues have been clipped at 300 ly from Sol.

Yale Trigonometric Parallaxes, Fourth Edition: The Yale catalogue (a.k.a the General Catalogue of Trigonometric Parallaxes, or GCTP) is a historical dataset that was one of the most accurate near star catalogues before Hipparcos, with parallax measurements taken from the ground-based observations. It includes many fainter stars that are not in the Hipparcos catalogue, but the distance accuracy is much lower. It also include many stars that are in the Hipparcos catalogue, but because of the lower accuracy they are somewhat shifted from their Hipparcos-derived positions – the difference increases with distance from Sol. However, the Yale catalogue does include Spectral data for most stars. As such, the Yale and Hipparcos catalogues should NOT be combined.

Source: http://vizier.u-strasbg.fr/viz-bin/VizieR?-source=I/238A/picat.
Number of star systems: 6,051
Distance range: 22.8 – 300 lightyears from Sol.
Accuracy: Positional data are less accurate than Hipparcos, but spectral data is included. Physical data are not accurate. All stars are listed as single stars.

Gliese Nearby Stars, Preliminary 3rd Version: The Gliese catalogue is one of the “classic” historical star catalogues – it was updated in 1991, and includes all stars known at the time within 25 pc of Sol, and a few that are further out. It has low accuracy, but again includes some of the dimmer stars that Hipparcos does not include. The 2300AD star map is apparently based on the 2nd version of this catalogue.

Source: http://vizier.u-strasbg.fr/viz-bin/VizieR?-source=V/70A.
Number of star systems: 3,667
Distance range: 22.8 – 300 lightyears from Sol.
Accuracy: Positional data are less accurate than Hipparcos, but spectral data is included. Physical data are not accurate. All stars are listed as single stars.

The HIPX data replaces the New Reduction Hipparcos data on this website – Astrosynthesis and Galactic XYZ data have both been updated! In most cases the HIPX XYZ data is identical to the New Reduction Hipparcos XYZs, but issues with the parallaxes for some of the multiple systems in the New Reduction data led to significant inaccuracies there – in those cases, the parallaxes were reverted back to the original Hipparcos parallax data (again, refer to the XHIP paper for further explanation).

The XHIP data includes more star names (including common/arabic names), which are also presented here. However, note that Gliese numbers higher than 3000 have been removed for ease of reference. Technically these numbers aren’t “Gliese numbers”, they’re “NN” or “Wo(oley)” numbers. Because this could cause confusion, I decided to remove them instead of editing them all, but this isn’t a huge loss since the stars can still be tracked using their HIP numbers or other names.

If you’ve been using the New Reduction data, then be sure to head over to my Stellar Mapping page to download the new Extended Hipparcos dataset!

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In other news, my Stellar Mapping page now has the Atomic Rockets Seal of Approval! This is Winchell Chung’s way of saying that he likes my work, and I’m very happy about that because I’ve been a fan of his Atomic Rockets website pretty much since it first appeared online (it’s a great resource for any SF fan)! His 3D Starmaps site is also one of the main inspirations for my own stellar mapping efforts! Thanks, Winchell!

CTIOPI dataset, looking corewards.

I have also edited the DENSE dataset to remove all the stars that were duplicated in CTIOPI and HIPPARCOS datasets – the most accurate data has been retained (the original DENSE dataset is no longer available here, though I may make it available again in a later blog update). The CTIOPI dataset has also been edited somewhat to remove duplicates (none of the CTIOPI stars have HIP numbers though, though it does include one star – HIP 3856 – that is missing from the Hipparcos dataset). All CTIOPI entries within 22.7 lightyears have also been removed to avoid overlap with RECONS.

This means that there should now be no duplicated stars at all if the RECONS, DENSE, CTIOPI and HIPPARCOS datasets are used together, so the combined dataset is now about as accurate as it can be. Full details of these edits can be found in the “CTIOPI-DENSE merging details” section in the Astrosynthesis.txt and Galactic.txt files contained in the new RECONS-DENSE-CTIOPI.zip file available from Section 2 of the Stellar Mapping page.

I’ve also updated and reorganised the Stellar Mapping page to (hopefully) make it easier to decide which datasets to use. If you have already downloaded the DENSE dataset then you should download it again to make sure you have the latest version!

The 2300AD Near Star Map

The 2300AD RPG – originally published by Game Designer’s Workshop in 1988 – presented an excellent gritty, realistic near-future hard sci-fi setting with lots of exploration, mystery, and interesting aliens. It’s also about to be republished by Mongoose Publishing as a setting for their version of the Traveller RPG!

One of 2300AD’s most interesting features is that the setting is built around a realistic (for the 1980s) Near Star List based on the Gliese Catalogue (2nd Version). FTL travel in 2300AD has a maximum range of 7.7 lightyears, resulting in the creation of “Arms” that extend from Sol to connect only the stars that are within this range of eachother (this limit can potentially be extended to 11.55 ly using Stutterwarp tugs, but this is expensive and uncommon).

There are three of these Arms, each colonised by a different political power in the setting – the French Arm, the Chinese Arm, and the American Arm. The French Arm stretches “upwards” from Sol towards Galactic North, ending at the orange giant star Arcturus. The American and Chinese Arms share the same beginning, but split off so that the American Arm heads Coreward/Spinward while the Chinese Arm sprawls around the (galactic) southern part of the solar neighbourhood.

Unfortunately the Near Star List (NSL) has not been updated for the new version of 2300AD. A lot of stars have been discovered in the solar neighbourhood since the late 1980s (as shown on my Stellar Mapping page), and the locations and distances of existing stars have been greatly refined since then too – so how does the updated stellar data affect the Arms?

Quite significantly, it seems. Here’s a overview (made in Astrosynthesis) showing all of the Arms plotted on an accurate starmap consisting of the RECONS, DENSE and Hipparcos stars within 50 lightyears.

The French, Chinese, and American Arms of 2300AD (coreward is to the right).

The systems with yellow labels are on the French Arm (routes are cyan), the ones with red labels are on the Chinese arm (routes are green), and the ones with green labels are on the American Arm (routes are white). The yellow dashed lines represent routes between two stars that were closer than 7.7 ly in the original NSL, but are actually more than 7.7 ly apart in the modern data. The red dashed lines represent routes that require connecting stars that don’t exist. As you can see, there are quite a few yellow dotted lines…

Next, we’ll look at the individual Arms in more detail and see where the problems lie.

 
The American Arm

The American Arm (3D view)

The American Arm (2D Map)

Extending roughly Coreward from Sol, the American Arm contains five “broken links” that are longer than 7.7 ly.

- The broken link between Serurier (Ross 154) and Broward (Wolf 1061) is problematic, since there are no stars between the two that can connect them directly, and since both stars are close to Sol is unlikely that any have yet to be discovered in that region. Instead, the shortest way to connect them is via a circuitous route that goes from Ross 154 (Serurier) to AX Microscopii to SCR 1845-635 to Gliese 682 (Davout) to 36 Ophiuchi (DM -26 12026) to Wolf 1061 (Broward).
- The HIP 86287 (New Melbourne) to HIP 83762 (Ross 863) route is also troublesome, since there are no known connecting stars and the gap is particularly wide at 17.8 ly (which precludes stutterwarp tugs as a solution). Both systems are beyond the RECONS 22.8 ly sphere, which opens the possibility that there may be undiscovered objects out there – this means that fictional M dwarfs or brown dwarfs can be added to connect the two systems, though the length and geometry of the gap requires at least three such fictional objects.
- HIP 83762 (Ross 863) to HIP 82003 (Botany Bay) is another wide gap of 14.3 ly. In this case however, it is possible to connect from Ross 863 to HIP 84794 (Gliese 669) to HIP 83043 (Gliese 649) and then to Zeta Herculis (Kingsland). Gliese 669 also itself connects to Zeta Herculis.
- Gliese 667 (DM -34 11626) can connect to HIP 84720 (DM -46 11370) via HIP 80018. Incidentally, Gliese 667 is known to have planets around it!
- Gliese 661 (Red Speck) can connect to Alpha Lyrae (Vega) via 2MASS 1835+325.

 
The Chinese Arm

The Chinese Arm (3D View)

The Chinese Arm (2D Map)

The Chinese Arm covers much of the solar neighbourhood “below” Sol (towards Galactic South), and includes several well-known stars. Officially, it begins at Delta Pavonis, which is reachable from Gliese 682 (Davout) on the American Arm. There are several broken links/points of interest on this Arm:

- The Delta Pavonis to Gliese 682 (Davout) link is broken, but they can connect via Gliese 693.
- The link between Gliese 832 (Xiuning) and Gliese 1 (Hunjiang) is broken, but the stars can connect via Epsilon Indi.
- “Rho Eridani” is actually two unrelated stars (Rho 1 and Rho 2) that are both hundreds of lightyears from Sol – the star in its place is actually “p Eridani”. Evidently, the authors of the original map misread the lower-case “p” and thought it was a greek lower-case “rho” (ρ), and this error was propagated in later editions.
- The Delta Pavonis to Beta Hydri and the p Eridani to 82 Eridani links are broken, which means that they (and Zeta Tucanae) are isolated from the rest of the Arm. There are no known stars able to connect them to the Arm – fictional red/brown dwarfs or stutterwarp tugs would be required.
- Although there are no known stars between p Eridani and 82 Eridani, 82 Eridani can be reached from Tau Ceti (and Epsilon Eridani) by going to Gliese 1061, then to DEN 0255-470 and then to 82 Eridani.
- Ross 780 (DM -15 6290) and Gliese 908 (DM +1 4774) are separated by 7.71 lightyears, which is [i]just[/i] over the stutterwarp range limit (by a mere 600 AU or so). This could be handwaved away as being within the operational tolerances of the stutterwarp drive, or an alternate route between the two systems via either Gliese 1002 or Gliese 1005 can be used instead.
- The DM +20 5046 (Doris) system is a fictional system that does not exist – in fact, the EQ Pegasi/Ross671 finger is a dead end. A K5 V primary seems a little bright to be unknown at this distance from Sol, which makes it hard to justify this star’s existence in this location. The closest system not on the Arm is Ross 775 (a close M V binary pair, unlikely to have a habitable world around them), which is 7.98 lightyears from Ross 671. The best solution is probably to relocate Doris’ worlds to Gliese 1002, which is a solo M V star (incidentally, Kanata – Doris’ mainworld – should be tidally locked to its star in either case).
- Qinyuan is not shown on major route on the Chinese Arm, but it is located in the UV/BL Ceti system.

 
The French Arm

The French Arm (3D View)

The French Arm (2D Map)

The French Arm extends “upwards” from Sol towards Galactic North, ending at Arcturus (Alpha Bootis). It is the most problematic of the Arms, containing several broken links and four systems that do not exist.

- The link between Sol and Wolf 359 (Nyotekundu) is broken, so we’re off to a flying start! There are no other known objects between Sol and Wolf 359, and since it is so close it is very unlikely that there would be an undiscovered brown dwarf that can be used to connect the two. At a distance of 7.78 ly from Sol, this system would probably be too far to risk “pushing” stutterwarp drives to reach it on a regular basis, and the 0.08 ly extra distance (equivalent to 5040 AU) beyond the limit is somewhat too far to traverse using STL drives. The only solution is to take a very long route around that traverses most of the current Chinese Arm – this route would go from Sol to Barnard’s Star to Ross 154 to AX Microscopii to Lacaille 9352 to YZ Ceti to Tau Ceti to Gliese 1061 to Kapetyn’s Star to Sirius to Procyon to DX Cancri to Lalande 21185 (Bessieres)!
- the link from Lalande 21185 (Bessieres) to Gliese 380 (Neubayern) is also broken. The stars that connect the two result in a somewhat circuitous route, going from Lalande 21185 to DX Cancri to Gliese 388 to 2MASS 0937+293 to Gliese 380. A brown dwarf directly between the two stars would also be a viable alternative, however.
- Queen Alice’s Star and Kimanjano are both fictional systems that are required to connect Gliese 412 (Augereau) to Beta Canum Venaticorum and Beta Comae Berenices (Nous Voila). There is an alternate route to Beta Canum that involves travelling from Gliese 412 to Gliese 388 to Ross 104 to Xi Ursae Majoris (the somewhat misleadingly named “Kie-Yuma”) to HIP 57802 (DM +36 2219) to Beta Canum – the worlds of Queen Alice’s Star and/or Kimanjano could be relocated to one of the stars on this route. However, there is no alternate route between Gliese 412 and Beta Comae Berenices, so it may be better to use Queen Alice’s Star and Kimajano for that purpose since fictional systems would be required to connect them.
- Berthier is a fictional system connecting 61 Ursae Majoris (Joi) and Beta Canum – it could have been intended to be Gliese 438.1, but this is actually an orange giant located over a thousand lightyears from Sol. This system is likely to be HIP 57050 – an M4 V star that is accessible from HIP 57939 (see below) and connects to 61 Ursae Majoris (HIP 57050 also is known to have a planetary companion).
- the 2300AD maps are somewhat ambiguous, and it could be that Henry’s Star (Crater) actually connects 61 Ursae Majoris to Beta Canum instead of Berthier. Henry’s Star is HIP 57939 (a.k.a. Gliese 451 or Groombridge 1830) – this is a metal-poor G8 VI subdwarf star that is known to “superflare”, so it wouldn’t be a good place for a habitable planet at all. That said, Crater isn’t all that habitable anyway, and as luck would have it the 2300AD Colonial Atlas mentions that Crater is regularly bombarded by flares from a companion star that is now known not to exist, so this works out pretty well!
- the link between Beta Comae Berenices and HIP 66459 (DM +36 2393) is broken, but HIP 66906 can be used to connect them.
- the link between HIP 66459 (DM +36 2393) and HIP 67422 (Hochbaden) is broken, and there are no known connecting stars. These are far enough from Sol that a fictional brown or red dwarf could be added to connect them though.
- the link between HIP 67422 (Hochbaden) and Eta Bootis (Aurore) is broken, but WD 1345+238 (a white dwarf from the DENSE catalogue) can be used to connect them. This also connects to Alpha Bootis (Arcturus).
- Gamma Serpentis (the Käfer homeworld) does still connect to Arcturus via HIP 75187 and HIP 72848.
- Vogelheim is a fictional system. It could be replaced by HIP 54646, which is the next star out from HIP 57087, towards Pentapod Space.
- the Bayern Corridor is described (in 2320AD) as being along the route to the Pentapod Homeworld (which is past HIP 57087). However, this would have been an extremely circuitous route for the Bayern to take to the Pleiades – a much more direct route would be to leave the Solar Neighbourhood from the vicinity of Omicron 2 Eridani on the Chinese Arm.

 
Conclusion

It is possible to squeeze the existing Arms into the realistic star map, but the significant problems with the French Arm reveal the proverbial elephant in the room, which is that the Arms do not follow the “natural flow” of the actual 7.7 ly routes between the stars – instead they leap across gaps that separate them. This is illustrated nicely at Sol itself – the only way to reach the surrounding stars from Sol (while remaining within the 7.7 ly limit) is to travel from Sol to Barnard’s Star to Ross 154 (Serurier) to AX Microscopii, from which one can join a web-like network of systems that extends in several directions. However, 2300AD has the French Arm leaping a gap to Wolf 359, and neither the American nor Chinese Arm go to AX Microscopii at all and leap to Wolf 1061 instead!

The animation below shows the real network of 7.7 ly links around Sol, along with the 2300AD Arms. The “real” network is shown as the grey links between stars (expand the video to full size to see the detail). This significantly changes the astrography of the setting, and will be discussed in subsequent posts.

Animation of realistic 2300AD links

I’ve now added Gliese 667 to the RECONS CSV files, so if you’ve already downloaded the RECONS data, you’ll need to download the new version so you can include Gliese 667! (I only found it because I was checking the stars on the American Arm for 2300AD!). There shouldn’t be any other missing stars there – I checked the border between RECONS and HIP and couldn’t find any other HIP stars within 22.8 ly that weren’t already on the RECONS list.

In this article I’m going to show you how to make your own stellar database, with the same tools I used to construct the ones I presented on my mapping page. For this exercise we’ll be relying on something called VizieR, which is a huge online database of thousands of star catalogues. You’ll need to have a basic understanding astronomy to make the most out of this, but it’s not that tricky.

Let’s say you want to make a database of stars in a corridor between Sol and the famous Pleiades star cluster (if you’re familiar with the 2300AD RPG, this is essentially the path the Bayern took to the Pleiades). We’ll be using the Hipparcos star catalogue, since it has the most accurate parallax measurements (from which we can derive distances).

Searching for a single star

0) First, we need to find the location of the Pleiades in RA/Dec. We know they’re in the constellation of Taurus, but we’ll need to be more precise than that! There are a number of named stars in the Pleiades (e.g. Maia, Alcyone, Pleione) so we’ll pick one of those – Alcyone is roughly in the middle of the cluster. It’s also in the Hipparcos catalogue – its wiki page (and other sources) tell us that its HIP number (Hipparcos catalogue number) is HIP 17702. Now we can look it up on VizieR!!

1) Go to http://vizier.u-strasbg.fr/viz-bin/VizieR?-source=I/311/hip2. This is the search form for the New Reduction of the Hipparcos database (the latest version of the Hipparcos data), and it looks like this:

2) Type “17702″ into the box that says “HIP”, and press Enter. This will generate a one-row table containing that star’s data.

3) Click the little black arrow in the sidebar on the left where it says “Compute”. This brings down a new menu with some checkboxes. You can use this to specify extra terms that the interface will calculate for you. In this case, tick the “J2000″ box. Also, select the “decimal °” button to get the J2000 RA/Dec in decimal degrees rather than in h/m/s format. This tells us that Alcyone is at RA 056.87115°, and Dec +24.10514° (these are alpha and delta respectively in the spreadsheets on my Stellar Mapping page), and has a parallax of 8.09 milliarcseconds (0.00809 arcseconds).

Now we know where Alcyone is, we can use this to generate a range of distances and coordinates in order to find the locations of all the stars in a corridor between Sol and Alcyone. The Pleiades spans about 2 degrees of sky in total, but we’ll actually need to make our “corridor” much wider than that if we want a decent number of stars between there and Sol – going about 10 degrees on either side of Alcyone would give us a good corridor.

Creating the corridor

4) Hit the back button on your browser to return to the search page, and remove “17702″ fom the HIP box.

5) Untick all the boxes in the “Show” column on the main page (left of the text boxes) except for the one next to “HIP”, and “Plx”. Make sure the sidebar settings are the same as they were before (see step 3) and change the “max” dropdown box there to “unlimited” and the box below that to “ascii table”. Now the results will be presented as an ASCII table, with just the computed J2000 decimal RA/Dec, the HIP number of the star, and its parallax.

6) In the “RArad” box, type “51.87 .. 61.87″. This tells VizieR to search between an RA of 51.87° and 61.87° (5 degrees either side of Alcyone in the sky).

7) In the “DErad” box, type “19.1 .. 29.1″. This tells VizieR to search between a Dec of 19.1° and 29.1° (5 degrees below and above Alcyone in the sky).

8‌) In the “Plx” box, type “6.5 .. 143.8″. This tells VizieR to show all the stars that have parallaxes between 6.5 and 143.8 milliarcseconds, which corresponds to a distance range of 22.7 to 501 lightyears from Sol (distance in lightyears = 3.2616/Parallax in arcseconds). We want the corridor to extend beyond Alcyone (whose parallax corresponds to a distance of 403 ly from Sol) so we can maximise our chances of getting the whole cluster.

The form should now look like this (click to expand image):

9) Press Submit to generate the list – you should get a list of 146 stars in ascii table format that looks like this:

Now we need to get this list of stars into the bulk_converter spreadsheet, so we can determine the Galactic XYZ co-ordinates for each star and (optionally) import it into Astrosynthesis.

Importing the list into Excel

10) Use your mouse to select and highlight the entire table in your browser and copy it into a text file. Save the text file as “input.txt” or something.

11) Import this file into Excel as a delimited, space-separated text file. You should end up with an Excel spreadsheet with 5 columns. The first is the index number of the star (which we don’t need), the second and third columns are the J2000 RA and Dec decimal degree coordinates (alpha and delta) of the star, the fourth column is the star’s HIP number, and the fifth column is the star’s parallax in arcseconds. All we need from this is the RA/Dec, parallax, and HIP number – you can delete the other columns.

12) We need to convert the parallax into milliarcseconds before we can import the parallax values. In an empty column, multiply the Parallax values by 0.001 for all the values in the parallax column (if your plx values are in column D, then in column E you would enter “=D1*0.0001″ (without the quotes) to calculate this). The table should then look like this:

13) Open up the bulk_converter.xlsx file from the Stellar Mapping page. It should have a sample star in it already:

14) Copy the data in the alpha and delta columns from the table you imported into Excel and paste them into Columns H and I in the bulk_converter file. Copy the HIP numbers from the imported file into column A of the bulk_converter file, and copy the recalculated parallax (in milliarcsecons) from the imported file into Column L of the builk_converter file (you’ll have to make sure you Paste Values for the parallax!). The first row of the pasted data should replace the sample entry already in the bulk_converter file, so you should end up with something that looks like this:

15) In the bulk_converter.xlsx file, copy the formulae in Columns J and K and Columns M to U down to the bottom of the sheet. You should see the empty rows fill up with the calculated galactic coordinates, distances, and X/Y/Z coordinates. The end result should look like this:

(Note: Columns B to G are empty since we’re importing the data as alpha and delta and not as sexagesimal RA/Dec, so you can just delete those columns).

Now we have all the information we need! If all you need are the Galactic Lat/Lon and/or Galactic XYZ co-ordinates then you can just delete columns S, T and U, save the file, and use it for whatever nefarious purposes you desire! However, if you want to import that into Astrosynthesis, then there’s one more sequence of steps remaining…

Importing the data into Astrosynthesis

Next, we need to create a CSV file to import the data in to Astrosynthesis – this has to be in a specific format:

16) Create a new Excel file (keep the edited bulk_converter file open in another window).

17) Fill out the new file as follows:
In column A, type “Star” into the first row. Astrosynthesis needs this to know what it’s reading.
In column B, type a big number like 10000 in the first row. This is the index number for the first star that we’ll import into Astrosynthesis – it needs to be unique.
In column C, paste the HIP numbers (column A of the edited bulk_converter file).
In Column D, E and F, paste the AS X, AS Y and AS Z values (Columns S, T and U of the edited bulk_converter file). Be sure to Paste Values here!
In Column G, type “0.5″ into the first row. This is a generic placeholder for the mass of the star (which we don’t know, but Astrosynthesis requires).
Column H and I should be blank.
In Column J, type “M0 V” into the first row. This is a generic placeholder for the spectral type and size of the star (which we don’t know, but Astrosynthesis requires).
Colummn K should be blank.
In Column L, paste the Distance/ly (column M of the edited bulk_converter file). Be sure to Paste Values here!

The file should look like this:

18) Each row needs its own unique number in Column B. In the second row, type “=B1+1″ (without the quotes) to increment the number you typed in the first row by 1. Copy this formula down to the end of the data. You should now have a list of increasing numbers in Column B.

19) Copy/paste the contents of Column A, G and J to the bottom of the data. The file should now look like this:

20) Save the file as a CSV (Comma delimited) file wherever you store your astrosynthesis data files (call it “AS3_pleiades.csv” or something). Press “OK” on the first window that pops up when you save (“save the sheet only?”, and “Yes” on the second window (“do you want to keep the workbook in this format”). When you close Excel, it will ask again if you want to save the file – say “no” since you’ve just saved it and haven’t made any changes.

21) Import the CSV into Astrosynthesis (see instructions in Section 3 of my Stellar mapping page).

22) Congratulations! You’ve now created your own Pleiades corridor, containing the Pleiades themselves and all the stars from the New Reduction Hipparcos catalogue that are between 22.8 and 500 lightyears from Sol! You can import this along with the RECONS data to fill in the stars up to 22.8 ly from Sol. If you like, you can replace the HIP numbers of the named stars in the Pleiades with their proper names too!.

The Pleiades Corridor! (including RECONS)

Hopefully there’s enough info here for you to figure out how to make other databases from these instructions too (e.g. if you want all the stars within 500ly of Sol, you can just enter the appropriate parallax range into the VizieR search form without entering any RA/Dec)!

RECONS dataset, looking towards the galactic core.

The focus has moved away from Traveller and its hex map format (I realised that I was taking accurate data and then making it inaccurate by forcing it into hex map format, so I’ve dropped that completely) and moved towards raw data and Astrosynthesis, but this will still be very useful for anyone interested in using realistic data for the stars near Sol.

You can check it out at http://evildrganymede.net/rpgs/stellar-mapping/

I’ll be writing some articles in the coming weeks to expand this – this will include how to use the Vizier stellar databases, and what this means for the 2300AD RPG!

I’ve finally added the “Further Star List” to my Realistic Near-Sol Astrography webpage – it’s an excel file containing accurate locations of a selection of major stars (including Vega, Deneb, 51 Pegasi, Spica, Bellatrix and Algol) that are more than 10pc from Sol.

The format is a bit raw (and I’m not entirely sure why I selected those specific stars to list!). The dark red X/Y/Z columns show the distances in each direction (Sol is the origin, +X is Coreward, +Y is Spinward, +Z is “above” Sol). If you have trouble interpreting it, let me know!

You can doublecheck the stars too – you can use the Convert spreadsheet in Section 1 of the mapping page to convert the RA/Dec of any stars into X/Y/Z coordinates. If you have astronomy software like Celestia, open it up and activate the Galactic Grid and rotate it so that you’re facing 0° latitude and 0° longitude – you’re now looking directly along the +X axis. Turn to look at 0° Lat, 90° Lon and you’re looking directly along the +Y axis. Look at the Galactic north pole, and you’re looking directly along the +Z axis. You should be able to find your stars using this (e.g. Aldebaran is pretty much directly along the -X direction, and down a bit on the Z axis. Look towards 180° Lon direction and -20° Lat, and there it is!).

I’ve been sitting on this for six and a half years (!!) and finally decided that I’m never going to draw hexmaps showing these stars, so I may as well just release the data and let other people figure it out! Enjoy!

The link is at http://evildrganymede.net/rpgs/stellar-mapping/.

(more info at http://www.universetoday.com/91170/ron-garans-incredible-iss-timelapse-coming-back-home/ )