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For the most representative sample of 277 most nearby galaxies, their masses, separations and tidal indexes were determined based on the BTA observations. It was shown that about 55% of galaxies in the Local Volume (D < 7Mpc) are dynamically centered systems. In the Local Universe at the scales of 0.3-3Mpc there is no evidence of segregation of galaxies by mass, however there exists a morphological type segregation: dwarf objects of later types dominate far from massive galaxies and also beyond the plane of the Local Supercluster. It was demonstrated that the relative number of interacting and merging galaxies in the Local Volume does not exceed 1-3%.
The most detailed light curve of optical star-like source (corresponding to the gamma-burst of May 8, 1997) was obtained from the BTA observations simultaneously in 4 photometric bands. At the maximum brightness of the source and straight after it, a slope of the continuum spectrum is measured. The variations of colors have been traced up to the 200th day after the burst. The brightness decrease rate and color indices were variable. An effect of an abrupt rate slowdown is noticeable in the infrared (~8000A) 36 days after the gamma-ray burst. These new facts drastically affect the currently emerging concept of the physical nature of gamma-ray bursts. We are probably observing the formation of a nebula, related to an ejection of matter during the gamma-ray burst, caused by the activity of a compact object like a neutron star.
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