The Local Group - The solar motion relative to its centroid

Abstract

The 21-cm redshifts for a number of galaxies are used to derive a solution for the motion of the local standard of rest relative to the centroid of the Local Group of galaxies. The solution for the motion of the local standard of rest is found to a best-fit solar motion relative to the Local Group centroid. Kinematic grounds (i.e. consideration of velocity residuals from the ridge-line solution of each galaxy) are cited in studying the membership of the Local Group. The error matrix for the calculations is also discussed.