Geodesic structure of Janis-Newman-Winicour space-time
  In the present paper we study the geodesic structure of the Janis-Newman-Winicour(JNW) space-time which contains a strong curvature naked singularity. This metric is an extension of the Schwarzschild geometry when a massless scalar field is included. We find that the strength parameter $\mu$ of the scalar field effects on the geodesic structure of the JNW space-time. By solving the geodesic equation and analyzing the behavior of effective potential, we investigate all geodesic types of the test particle and the photon in the JNW space-time. At the same time we simulate all the geodesic orbits corresponding to the energy levels of the effective potential in the JNW space-time. 
Sheng Zhou, Ruanjing Zhang, Juhua Chen and Yongjiu Wang
gr-qc