This book presents and discusses current research in the study of magnetohydrodynamics. Topics discussed include consideration of the problems of gravitational optics and dark matter based on the crystal model of the vacuum; origin of the Saturn rings; high speed flowfield analysis for satellite launch vehicle and re-entry capsule; MHD flow of a micropolar fluid with asymmetric wall temperatures; Na and Hansen's procedure for solving the MHD flow around a cylinder in cross electric and magnetic fields; and, a unified approach to analytical solution of an unsteady MHD generalised couette flow with transpiration.