A second part of the pre-perihellon photoelectric measurements of P/Halley obtained at the Skalnaté Pleso Observatory is presented. The observations cover 9 nlghts from November 8, 1985 to January 5, 1986. A set of focal diaphragms of the followlng diameters was used: 29.53", 48.98", 81.08", 137.34" and 220.53". Results of thls paper are magnltudes in focal diaphragms in the fllters Cont. 365.0 nm, Cont. 484.5 nm, CO^, C2, C3 and CN. Coma diameters, photometric parameters and continuum colors are also determined.
The dynamical evolution of meteor stream particles in resonance appear to be affected by the same resonance mechanisms as rcsonant asteroids. Crossing of separatrix.like zones appears to be crucial for the formation of arcs and for the dissolution of streams.
Investigating the orbital evolution of known resonant meteor streams and of model streams, we have found examples for such a transitory are formation. The orbital inclination of a meteor stream appears to be a critical parameter for arc formation.
Preliminary results of an extended program of examination of the Ondřejov and Sonneberg plate collectons for possible optical counterparts to gamma-ray bursters are presented. One optical image was found on 3 different plates at the same position suggesting it may be related to gamma-ray burster 1979 March
25 B. Results of both archival and time-correlated searches are discussed for GRBS as well as for the Perseus Flasher.
The outbursts of cometary brightness háve been attracting the astronomers attention for more than a hundred of years. They play a significant role in the study of physical nature and evolution of comets. An outstanding Soviet astronomer S.K. Vsekhsvyatsky (i)
pointed out the corpuscular fluxes as a plausible factor being responsible for the variation of cometary brightness. He was the
first to suggest that the effect of fragmentation of solar corpuscular fluxes on cometary ices is one of the causes generating the
brightness outbursts.
In this paper, two different analytical techniques for solving visual double star orbis with inclination equal to 90° are given. The first is based on Docobo´s method, and the second is derived by using the Fourier Transform for angular distances. Both techniques are applied to the pairs 1919252442 and 1933882339.