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In accordance with the principles of open science, the results of the research should remain available for further investigations and practical interaction with them in the research community. Such results include collected initial and obtained data, specifications and implementations of methods applicable to them including data integration rules, and other possible resources. At the same time, the results of research on data should be curated to maintain their relevance, compliance with domain development, and standards in order to make them as useful as possible in the long term. A research support system in the research domain of physics of stellar systems is being developed to provide relevant data and methods, classify them, make them findable, avoid multiple integration of heterogeneous data, and integrate them into ongoing research in the astrophysical community. New catalogues are being added on regular basis, and this process is accompanied by correct cross-identification of the entities. New observational types of binary stars with their features are added to binary star database (https://bdb.inasan.ru).

We determine the interstellar extinction in the selected high-latitude areas of the sky based on Gaia EDR3 astrometry and photometry and spectroscopic data from RAVE survey. We approximate the results with the cosecant law in each area thus deriving the parameters of the barometric formula for different lines of sight. The distribution of the parameters over the entire sky is described using spherical harmonics. As a result, we get a mathematical description of the interstellar visual extinction for different lines of sight and distances from the Sun which can be used for estimating interstellar extinction.

We introduce the application of the clustering algorithm to the preliminary compiled list of probable wide pairs of co-moving stars. The main aim of such development is a possibility of unsupervised blind search of coeval loose stellar structures over significant regions in space. Using Gaia EDR3 data, we investigated the application of the method to nearby region hosting recently discovered loose structures – tidal tails of Coma Ber star cluster and a nearby stellar group named Group X. We compare the results of straightforward clustering of stellar data with results of using our method with varying parameters. We then compare the results of our method to the recent results of the two groups of authors who independently discovered the discussed structures. We find parameters allowing the method to find the full scope of distributed stellar groups without preliminary knowledge of their characteristics. It decreases the risk of false positive clustering and improves the ability to discover loose stellar groups, in comparison with the application of clustering algorithm to the individual stars. Further we obtain a refined dataset of probable members of both stellar groups and independently obtain their ages (700 ± 70 Myr and 450 ± 100 Myr) and space velocities ((U,V,W) = (8.63 ± 0.13, 6.63 ± 0.20, 6.65 ± 0.95) km/s for Coma Ber star cluster, and (U,V,W) = (7.70 ± 0.12, 3.27 ± 0.45, 5.69 ± 0.80) km/s for Group X). Our results are in very good agreement with those of previous investigators.

Information on interstellar extinction and dust properties may be obtained from modern large photometric surveys data. Virtual Observatory facilities allow users to make a fast and correct cross-identification of objects from various surveys. It yields a multicolor photometry data on detected objects and makes it possible to estimate stellar parameters and calculate interstellar extinction. A 3D extinction map then can be constructed. The method was applied to 2MASS, SDSS, GALEX and UKIDSS surveys. Results for several high-latitude areas are obtained, compared with independent sources and discussed here.

The goal of this researchwas to compare the open cluster photometric distance scale of the global survey of star clusters in the MilkyWay (MWSC) with the distances derived fromtrigonometric parallaxes fromthe Gaia DR1/TGAS catalogue and to investigate towhich degree and extent both scales agree.We compared the parallax-based and photometrybased distances of 5743 cluster stars selected as members of 1118 clusters based on their kinematic and photometric MWSC membership probabilities. We found good overall agreement between trigonometric and photometric distances of open cluster stars. The residuals between them were small and unbiased up to log(d, [pc]) ≈ 2.8. If we considered only the most populated clusters and used cluster distances obtained from the mean trigonometric parallax of their MWSC members, the good agreement of the distance scales continued up to log(d, [pc]) ≈ 3.3.