Detailed monitoring of the water vapor maser in the binary protostellar system of solar masses IRAS 16293-2422 A. E. Volvach 1, L. N. Volvach 1, M. G. Larionov 2 1 Radio Astronomy of Crimean Astrophysical Observatory RAS, Katsively, Crimea 2 Astro Space Center, Lebedev Physical Institute RAS, Moscow Unique results of detailed (one-two days interval between data) one-year monitoring of the young binary system IRAS 16293-2422, performed on the RT-22 radio telescope (Simeiz), are obtained. For the first time, a short, powerful flare of a water vapor maser was recorded (feature +8 km/s), which is a combination of three components. New data on the parameters of the medium in which maser radiation is formed was obtained.