Observations of Jupiter's Galilean satellites in the Ordubad expedition of the Main Astronomical Observatory of the USSR Academy of Sciences in 1984-1986

Positional observations of Jupiter's Galilean satellites at Ordubad during 1984-1986 are reported. The correction for Jupiter's solar phase in the coordinate difference 'satellite minus Jupiter' is studied. The best correction is implemented on the basis of the geometric law with the coefficient K_x = K_y = 3. The internal error of a single observation of each of the four satellites is obtained from a comparison of the coordinate differences with the G-5 theory.