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The 2009 WZ104 asteroid was discovered with 68-cm Schmidt Catalina Sky Survey telescope of Mount Lemmon Observatory in Arizona (USA) in 25 of November 2009. The observations of the new object were confirmed with 60-cm reflector of Schiaparelli observatory (Italy) and 35-cm Schmidt - Cassegrain telescope of Alter Saltzberg observatory (Vienna, Austria). The asteroid was attributed as potentially hazardous near Earth asteroid. The minimal orbit intersection distance is 0.0304 a.e. The observations of the 2009 WZ104 asteroid were continued with MTM-500M 50-cm meniscus telescope and ZA-320M 32-cm mirror astrograph of Pulkovo observatory (Russia) since late 2009. The observations were made in the framework of NEOs investigation program. The following tasks were established for the investigation: to get astrometric and photometric (in BVRI bands) series of observations, to improve the asteroid orbit on the base of the observational data, to determine its taxonomic class and absolute magnitude, to investigate the dynamics of its rotation, to estimate its physical parameters. The asteroid was attributed to Aten group among NEAs., Comment: 8 pages, 4 figures, 8 tables

During close angular approaches of solar system planets to astrometric radio sources, the apparent positions of these sources shift due to relativistic effects and, thus, these events may be used for testing the theory of general relativity; this fact was successfully demonstrated in the experiments on the measurements of radio source position shifts during the approaches of Jupiter carried out in 1988 and 2002. An analysis, performed within the frames of the present work, showed that when a source is observed near a planet's disk edge, i.e., practically in the case of occultation, the current experimental accuracy makes it possible to measure the relativistic effects for all planets. However, radio occultations are fairly rare events. At the same time, only Jupiter and Saturn provide noticeable relativistic effects approaching the radio sources at angular distances of about a few planet radii. Our analysis resulted in the creation of a catalog of forthcoming occultations and approaches of planets to astrometric radio sources for the time period of 2008-2050, which can be used for planning experiments on testing gravity theories and other purposes. For all events included in the catalog, the main relativistic effects are calculated both for ground-based and space (Earth-Moon) interferometer baselines., Comment: 8 pages, 5 tables