Galactic rotation and solar motion from stellar kinematics

Abstract

I present three methods to determine the distance to the Galactic centre R 0 , the solar azimuthal velocity in the Galactic rest frame V g, and hence the local circular speed V c at R 0 . These simple, model-independent strategies reduce the set of assumptions to near axisymmetry of the disc and are designed for kinematically hot stars, which are less affected by spiral arms and other effects.