ИСТИНА

The Moon's gravitational field had been studied long before the launch of the first artificial satellites of the Moon. M.U. Sagitov and N.P. Grushinsky, employees of Sternberg Astronomical Institute of Moscow State University, have calculated gravity on the lunar triaxial ellipsoid using astrometric observations. They have proposed a model in which the gravitational field of the Moon can be represented by a field of a triaxial ellipsoid, the polar axis of which is perpendicular to the ecliptic, and the large lunar ellipsoid equatorial axis is directed towards the Earth. The studies have shown that the force of gravity on the Moon increases from the poles to the equator by approximately 0.0004 of its full size. Later on the gravitational field was determined by observation of artificial satellites of the Moon. The observations confirmed that the ellipsoid of the Moon is prolate towards the Earth. The Ferrari’s model of the triaxial ellipsoid of the Moon shows that the height of the surface level over the ball towards the Earth is 400 meters and 300 meters - from the back side of the Moon. In 1968, based on the study of the radial acceleration of the Moon’s artificial satellite, Lunar Orbiter 5, American scientists P. Muller and U. Seagren found large positive anomalies over the Mare Imbrium, the Mare Serenitatis, and the Mare Crisium. At the altitude of the satellite (100 km), gravity anomalies reached 200 mGal and more. In particular, over the Mare Imbrium gravity anomaly was equal to 250 mGal, over the Mare Serenitatis - 220 mGal, over the Mare Crisium - 130 mGal. Origin of positive anomalies is related to the concentration of heavy masses in the ground, these structures are called mascons. Gravity map of the Moon made by the Lunar Prospector probe in 1998-1999. Mascons are marked with red and orange: 5 most significant of them are associated with five lunar seas. New data on the gravitational field of the Moon were obtained from two Grail spacecrafts. The spacecrafts were launched on September 10, 2011 and received the names of Ebb and Flow. The probes flew on the same orbit, one after the other at a height of 55 km above the lunar surface. The distance between the spacecrafts was recorded with micron accuracy and varied depending on the magnitude of the gravitational field when spacecrafts were passing over the visible morphological objects, which included mountains, craters, and also massive objects hidden under the surface of the Moon. According to the GRAIL mission data, there has been made a unique map of the Moon's gravitational field. The probes revealed the existence of long, hundreds of kilometers, gravity anomalies, here and there coming out to the surface. Most probably, they indicate that under the surface there are long and elongated, narrow "shafts" of dense magma solidified a long time ago. Many volcanic structures have been found by the Grail spacecraft. These are tectonic structures, basins of impact craters, ancient linear gravity anomalies. The article presents the data of the chemical composition of the surface soil layer of the lunar Maria. All measurements have been performed according to the theoretical models of light scattering on the basis of survey of the lunar surface by in-orbit spacecrafts and analysis of the lunar soil samples.