Michel velocity, given by Eq. (9), as a function of stellar rotation rate. The solid blue and red lines are for stellar masses of 0.5 M_⊙ and 1.0 M_⊙ respectively, and the dashed black and red lines show the speeds of the slow and fast components of the solar wind respectively. The dotted lines show our estimates for the highest wind speeds possible for purely thermal pressure driven winds, calculated assuming Model A for the wind temperature.