During the 2014-2015 mutual events season, the Institut de Mecanique Celeste et de Calcul des Ephemerides (IMCCE), Paris, France, and the Sternberg Astronomical Institute (SAI), Moscow, Russia, led an international observation campaign to record ground-based photometric observations of Galilean moon mutual occultations and eclipses. We focused on processing the complete photometric observations data base to compute new accurate astrometric positions. We used our method to derive astrometric positions from the light curves of the events. We developed an accurate photometric model of mutual occultations and eclipses, while correcting for the satellite albedos, Hapke's light scattering law, the phase effect, and the limb darkening. We processed 609 light curves, and we compared the observed positions of the satellites with the theoretical positions from IMCCE NOE-5-2010-GAL satellite ephemerides and INPOP13c planetary ephemeris. The standard deviation after fitting the light curve in equatorial positions is +/- 24 mas, or 75 km at Jupiter. The rms (O-C) in equatorial positions is +/- 50 mas, or 150 km at Jupiter.

In 2009, in five Russian observatories photometric observations of Jupiter’s Galilean satellites during their mutual occultations and eclipses were carried out. Based on these observations, an original method was used to ascertain astrometric results such as the difference between the coordinates of pairs of satellites. Fifty-three phenomena were successfully observed. A total of 94 light curves of satellites were measured. The error in the coordinates of satellites due to random errors in photometry, calculated on all data obtained, was 0.041″ in right ascension and 0.046″ in declination. The discrepancies between the theory and observations in these coordinates was found to be 0.060″ and 0.057″, respectively. The results were uploaded to the common database for all observations of natural satellites of planets at the Natural Satellites Data Center (NSDC), which is available online at http://www.sai.msu.ru/neb/nss/index.htm . For the first time in the practice of photometric observations of satellites in epochs of mutual occultations and eclipses a new method of observation was tested, which eliminates from astrometric results the major systematic errors caused by an inaccurate account of the background level. The tests were conducted in the Terskol Observatory and the observatory of the Crimean laboratory of the Sternberg State Astronomical Institute of the Moscow State University. The application of the new method showed that the elimination of the background level at these observatories was carried out correctly.

We report the final results of the 1997 campaign of photometric observations of the mutual phenomena of the Galilean satellites carried out at observatories in Kazakhstan, Russia, and Ukraine. Our results contribute substantially to the world data bank of such observations and will allow the model of the motion of Galilean satellites to be further refined. To facilitate the use of photometric data, we reduced them by computing the planetocentric rectangular coordinate differences of satellite pairs for a number of instants of time so we deduce the differences for one instant from one observed light curve. It is these reduced data tl:lat constitute the principal result of this work. We based our data reduction on the method which we det-eloped in earlier papers (Emel'yanov 1999; Emel'yanov 2000). The accuracy of observations was estimated in the process of reduction. The paper also describes the equipment used.