  We investigate the binary star T Tauri South, presenting the orbital
parameters of the two components and their individual masses. We combined
astrometric positions from the literature with previously unpublished VLT
observations. Model fits yield the orbital elements of T Tau Sa and Sb. We use
T Tau N as an astrometric reference to derive an estimate for the mass ratio of
Sa and Sb. Although most of the orbital parameters are not well constrained, it
is unlikely that T Tau Sb is on a highly elliptical orbit or escaping from the
system. The total mass of T Tau S is rather well constrained to 3.0 +0.15/-0.24
M_sun. The mass ratio Sb:Sa is about 0.4, corresponding to individual masses of
M_Sa = 2.1+/-0.2 M_sun and M_Sb = 0.8+/-0.1 M_sun. This confirms that the
infrared companion in the T Tauri system is a pair of young stars obscured by
circumstellar material.
