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We present the results of study the 2D distribution of galaxies in 254 rich open galaxy clusters. The clusters have no concentration to the center, so all kinds of substructures are clearly seen. Regular linear substructures in galaxy clusters were described in Rood & Sastry scheme of morphological types according to positions of 10 brightest galaxies. Another types of regular substructures were missed. Our study fills the lacuna. We have found about 25% of clusters in our data set having four kinds of regular substructures, beyond founded before linear ones. New kinds of regular substructures are: crossing and divaricating filaments or X and Y-type peculiarities, as well as curved strips and short dense chains. We suppose the distribution of dark matter in founded galaxy clusters with substructures have corresponded regular peculiarities. Hot gas distribution in these clusters must be observed distorted X-ray halo. We suppose also the clusters will evolve in the different ways.

Careful analyses of photometric and star count data available for the nine putative young clusters identified by Camargo et al. (2015, 2016) at high Galactic latitudes reveal that none of the groups contain early-type stars, and most are not significant density enhancements above field level. 2MASS colours for stars in the groups match those of unreddened late-type dwarfs and giants, as expected for contamination by (mostly) thin disk objects. A simulation of one such field using only typical high latitude foreground stars yields a colour-magnitude diagram that is very similar to those constructed by Camargo et al. (2015, 2016) as evidence for their young groups as well as the means of deriving their reddenings and distances. Although some of the fields are coincident with clusters of galaxies, one must conclude that there is no evidence that the putative clusters are extremely young stellar groups., Accepted for publication (MNRAS)

We have made the first attempt to derive the chemical properties of the Galactic disc at its very central part using high-resolution infrared spectroscopic observations of four classical Cepheids. These stars are located at Galactocentric distances smaller than 1 kpc. All investigated stars show near-to-solar elemental abundances. By combining these new data with our previous studies, our results suggest that the radial distribution of iron abundance on a logarithmic scale gradually increases from the outskirts of the Galactic disc to Galactocentric distances of about 2–4 kpc. There, it reaches a maximal value of about +0.4 dex, and then declines sharply to about the solar value at the Galactic Centre.

We present the results of analysis of 2D distribution of galaxies in galaxy cluster fields. The Catalogue of Galaxy Clusters and Groups PF (Panko & Flin) was used as input observational data set. We selected open rich PF galaxy clusters, containing 100 and more galaxies for our study. According to Panko classification scheme open galaxy clusters (O-type) have no concentration to the cluster center. The data set contains both pure O-type clusters and O-type clusters with overdence belts, namely OL and OF types. According to Rood & Sastry and Struble & Rood ideas, the open galaxy clusters are the beginning stage of cluster evolution. We found in the O-type clusters some types of statistically significant regular peculiarities, such as two crossed belts or curved strip. We suppose founded features connected with galaxy clusters evolution and the distribution of DM inside the clusters.