ИСТИНА

n the course of MESSENGER mission the manmade Mercury moon completed more than 4000 orbits. Approximately one fourth part of the time which MESSENGER spent on the orbiting about Mercury it was located inside the magnetosphere and transferred magnetometr data to the Earth. Using the likelihood function and FORTRAN code FUMILIM (from the CERN program library) we determined the time dependence of the Mercury magnetospheric current systems’ parameters for 60 orbits on March 2011 at the beginning of the MESSENGER orbiter mission. These data give a possibility to extract the regions of the orbits (near the magnetopause and bow shock crossings) where magnetic field has a strong variation due to different plasma instabilities. Also we can estimate the relative errors in the planetary dipole offset and strength. Due to the small size of the Mercury magnetosphere, the magnetic field contributions to the total magnetospheric field of the inner planet current and the magnetospheric current systems are almost equal. The resulting rms deviation of the model field and the measured magnetospheric field vector components are about ten nT. This is more than twice smaller than the rms errors of the average magnetospheric model similar to KT17 which ignored the variations of magnetospheric field from one orbit to another and gives the rms about 18.5 – 34.4 nT.