Stellar velocity distribution 



63 



Compared moment of the velocities of the stars surrounding: 



the galactic plane , the galactic pole , Corresponding 



(Mean tz = 0.0135 (Mean n = 0.0181) value of q' 



N 002 compared with N 0M + 0.611 



N m » F 20o + 0.409 



^200 » ^002 +0.542 



2V 020 » N W2 +0.630 



Comparison over the whole sky (difference of parallaxes considered) 



corresponding 

 value of q' 



between iV 2oü and N 002 + 0.467 



N 020 » N 00i +0.467 



Comparison over the whole sky (parallaxes adopted = 0.0163 .) 



between JV 2(J0 and N im + 0.493 



There seems to be no doubt that a mean value of q equal to + 0.60 derived 

 from the first four equations will statisfy the equation (52). However, the numerical 

 values of q obtained in the different ways are probably too small, but on the 

 other hand a variation of the mean parallax, or a variation of the sun's relative 

 velocity will largely influence the results. 



Indeed it was shown, first by Charlier and then by Wicksell, that a value 

 of q so small as -f O.fiO will not suit the moments of the third and fourth orders, as 

 derived from proper motion observations, which moments for the value q = 0.60 

 are very much diverging from zero. The relative velocity of the sun is then 

 assumed to be 20 km per second. 



For the rest I refer to the authors cited. 



