3d Star Maps

[BillDowns]

Just an amusing observation about 3d star maps. Of the real universe, not Traveller, necessarily.

I picked 4 maps from the internet and observed the relative positions of 5 stars: Sol, Alpha Centauri, Barnard's Star, Wolf 359 and Sirius. None of the 4 maps agree with each other. LOL

http://kisd.de/~krystian/starmap/
http://www.atlasoftheuniverse.com/12lys.html
http://www.bodurov.com/NearestStars/
http://www.solstation.com/map27ly.htm

Which one is right?

 

[whulorigan]

Just an amusing observation about 3d star maps. Of the real universe, not Traveller, necessarily.

I picked 4 maps from the internet and observed the relative positions of 5 stars: Sol, Alpha Centauri, Barnard's Star, Wolf 359 and Sirius. None of the 4 maps agree with each other. LOL

http://kisd.de/~krystian/starmap/
http://www.atlasoftheuniverse.com/12lys.html
http://www.bodurov.com/NearestStars/
http://www.solstation.com/map27ly.htm

Which one is right?

Go here:

SIMBAD Astronomical Database
http://simbad.u-strasbg.fr/simbad/sim-fid

- Type the Star name in the Identifier Text Box and click "submit id"

- On the page generated, the row labelled "Gal coord" has the Galactic Coordinates for the star:

- The first number is the bearing (azimuth) within the galactic plane: 000.0 is coreward, 090.0 is spinward, 180.0 is rimward, and 270.0 is trailing;
- The second number is the altitude angle +/- 90.0 above/below the galactic plane
​

- The row labelled "Parallaxes mas" is the obsereved parallax in milli-arc-seconds. That means if you divide 1000 by the number shown, you have the observed distance in parsecs.


So for Alpha Centuari:

Gal coord.: 315.7330 -00.6809
Parallaxes (mas): 742

Meaning that it lies at bearing ~315^o (due coretrailing), at an angle ~00.68^o degrees below the galactic plane

Its distance from Earth is 1000/742 = ~ 1.35 parsecs.