# State vectors of “interesting” multiple stars

I'd like to show a demonstration of Runge Kutta integration of real systems using examples of interesting multiple stars, where "interesting" means you can see through a small telescope that they are at least double. I've selected three:

1. Gamma Andromedae (Almach)
2. Alpha Geminorum (Castor)
3. Zeta Ursae Majoris (Mizar and Alcor)

How can I find a state vector (set of relative positions and velocities) - or something similar - for these multiple star systems? An open access link (for everyone) would be great, but a journal reference is fine as well if that's what it takes.

Of course the periods are long and there will be uncertainty - I'd just like to use whatever is known and available, for this demonstration.

1. $\gamma$ And is WDS 02039+4220
2. $\alpha$ Gem is WDS 07346+3153
3. $\zeta$ UMa is WDS 13239+5456