Аңдатпа
Abstract Observations of radial velocities in the F-corona in the elongation range from 3 to 6 solar radii were carried out on July 11, 1991 (Mexico, La Paz) by means of a Fabry-Perot spectrograph. The Fraunhofer lines in the spectral region of H and K Call were used. The average velocities to the West and to the East of the Sun within 30° of the ecliptic plane are +30 km/s and -27 km/s respectively. This confirms the main results of the F-corona radial velocity observations by Shcheglov et al. (1987), Shestakova (1987) on July 31, 1981 about predominance of prograde Keplerian motion of the dust near the ecliptic plane and the effective radius of dust grains (≈0.4μm)