You can convert the distance, RA and Dec of a star into X,Y and Z cartesian coordinates by using the formula:
X = D cos(RA) cos(Dec) Y = D cos(RA) sin(Dec) Z = D sin(RA)
where you convert RA into degrees by multiplying its decimal value by 360/24. D is the distance to the star in light years which you can get from a table of, say, the nearest stars. The RA and Dec coordinates are also given there. Example, for a star 10 light years away at RA = 6h 00m 00s and Dec = +45degrees, RA = 6 x 360/24 = 90 degrees, and so X = 0, Y = 0 and Z = D=10 light years.
Copyright 1997 Dr. Sten Odenwald
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