Creating an interstellar empire (2 of 2)

[jude_rook]

Last time we used the HabHyg database to create an empire made up of Gliese 838, plus all the other known stars located with a 6 x 6 x 6 parsec cube with Gliese 838 at its centre.  What stars have we got? (By the way, since I prefer light years to parsecs, from here on I’m just going to use the former in describing distances.)

Gliese 838.6: an M3 star 2.1 light years from Gliese 838 and 49.2 from Sol. XYZ coordinates are: 30.97, -4.89 and -37.82.

Gliese 841 A and B: an M0 star with a white dwarf companion, 4.25 light years from Gliese 838 and 52.8 from Sol.  XYZ coordinates are: 33.25, -9.13 and -40.10.

HD 205390/Gliese 833: a K2V star 4.5 light years from Gliese 838 and 47.9 from Sol. XYZ coordinates are: 32.27, -7.82 and -34.88.

NN 4198: an M3 star 6.5 light years from Gliese 838 and 52.5 from Sol. XYZ coordinates are: 35.86, 0.65 and -38.47.

Woolley 9724: an M1 star 7.5 light years from Gliese 838 and 46.6 from Sol. XYZ coordinates are: 33.90, -1.63 and -31.95.

NN 4224, an M6 star 8.5 light years from Gliese 838 and 43.7 from Sol. XYZ coordinates are: 28.04, -0.33 and -33.58.

HD 211415/Gliese 853 A and B, a G2V star with an M companion, 9.4 light years from Gliese 838 and 44.3 from Sol. XYZ coordinates are: 25.75, -9.78 and -34.56.

NN 4178, an M star 9.8 light years from Gliese 838 and 57 from Sol. XYZ coordinates are: 42.05, -8.80 and -37.82.

HD 211970/GJ 1267: a K7V star, 10.3 light years from Gliese 838 and 43.7 from Sol.  XYZ coordinates are: 25.10, -10.43 and -34.23.

GJ 2151/Woolley 9716: an M4 star 10.9 light years from Gliese 838 and 46.3 from Sol. XYZ coordinates are: 33.25, -12.06 and -29.99.

Of these stars, HD 205390/Gliese 833, HD 211415/Gliese 853 A and HD 211970/GJ 1257 look to me like not-bad bets to have habitable planets.  In fact, HD 211415 is one of Margaret Turnbull’s top choices for a system with a habitable world.  And of course the smaller, cooler stars are not absolutely ruled out. 

To figure out how far any two stars in the empire are from each other, put star 1’s XYZ coordinates into cells A1, B1 and C1 of an Excel spreadsheet, and star 2’s into D1, E1 and F1.  Then, in another cell, enter this formula: =SQRT(((A1-D1)^2)+((B1-E1)^2)+((C1-F1)^2)).

If you want to write a story about two empires, you can create a cube that is larger than the empire you want to make from it, and pick a star in one of the “corners” to be the centre of the second empire.  Stars that are located about equally far from both capitals can function as disputed territory.

There are a couple of ways you can make a star map of your new empire.  I’ve already described one way here, but there’s another method that might be more appropriate for an area of space, like this one, that’s a ways off from Sol.  I’ll get to it in the next entry.