Resolved spectroscopic binaries (RSB) are unique objects among other types of binaries. They provide the only possibility (apart from trigonometric parallaxes) to determine with high precision the distances to objects - the most important characteristic in astronomy. Binary systems of this type are few in number, but an exhaustive catalogue still does not exist. The lecture gives basic concepts about observational and astrophysical characteristics of binary systems of different types, describes RSB in detail, and presents a pilot version of a new catalogue of resolved spectroscopic binary systems. A preliminary analysis of the distributions of stellar parameters of the catalogue objects has been carried out, and the trigonometric parallaxes from Gaia DR3 have been compared with the orbital parallaxes.

We will acquire Gaia DR3 data in the Pleiades star cluster region to select cluster members, based on position, proper motion, and parallax data. We will construct a color-magnitude diagram. The TOPCAT package will be use.

An expert forecast on the development of astronomy was prepared in 2009. A list of 35 questions was compiled by Russian astronomy popularizers. Each question begins with "When", e.g. "When a human will land on the Mars?" or "When white holes will be discovered?". The list was independently checked and corrected by scientific journalists. Russian astronomers were asked to answer the questions. The questionnaire was also available to amateurs and enthusiasts of astronomy through the Internet. Results of the opinion poll and comparison with reality are presented here.

The Hertzsprung-Russell diagram (HRD) is a scatter plot of stars showing relationship between absolute magnitudes or luminosities of stars with respect to their stellar classifications or effective temperatures. We will construct an HRD based on VizieR and Gaia DR3 data obtained using the CDS X-Match service and the TOPCAT package.

The International Satellite Program in Research and Education (INSPIRE) is a worldwide consortium of space-focused Universities initiated by the University of Colorado at Boulder (CU Boulder-LASP) along with its global academic collaborators. Its primary aim is to promote advancements in space science and engineering. INSPIRE's small satellite projects are designed to progress from concept to launch within a three-year period, offering undergraduate and graduate students hands-on experience in designing, building, testing, and managing small satellite missions. This initiative integrates science, engineering, and management principles across University campuses worldwide, aspiring to deploy a constellation dedicated to observing Earth and space weather. Currently, the program encompasses eight satellite missions. This presentation will provide an overview of the eight satellite missions within the INSPIRE program. We will then focus in detail on three specific missions: Inspire-5, Inspire-7, and Inspire-X. These missions are particularly aimed at measuring Earth's radiative budget and monitoring greenhouse gases emissions (CO2 and CH4).

An introduction to one of the greatest scientists of the 20th century Viktor Ambartsumian (1908-1996) and the Byurakan Astrophysical Observatory (BAO) founded by him in 1946 and led for many decades. Ambartsumian was one of the founders of the Theoretical Astrophysics, the President of the Armenian Academy of Sciences (1947-1993), National Hero of Armenia (1994), USSR State Prize winner (twice), the President of the IAU (1961-1964) and its Vice-President (1948-1955), founder of Chairs of Astrophysics in Leningrad (presently St. Petersburg) and Yerevan State Universities, founder of the journal Astrofizika (Astrophysics). Beside Ambartsumian’s theoretical achievements, BAO is well known by its surveys (Markarian Survey, Arakelian galaxies, Shahbazian groups and others) and discovery of dozens of thousands of new cosmic objects: T Tau and flare stars, HH objects, cometary nebulae, carbon stars, white dwarfs, cataclysmic variables, Novae and Supernovae, UV-excess galaxies, AGN, Starbursts, compact groups of compact galaxies (Shahbazian groups), etc. At present, BAO has official status by the Armenian Government as National Value, IAU South West and Central Asian Regional Centre of Astronomy for Development, IAU Outstanding Astronomical Heritage (OAH), as well as Markarian Survey has entered the UNESCO "Memory of the World" documentary heritage list.

Astronomical Surveys are the main source for discovery of new astronomical objects and for astronomical/astrophysical research. In the era of Multiwavelength (MW) and Multimessenger (MM) Astronomy, MW surveys become the most crucial for full understanding of the Universe, the Milky Way and individual objects. Astronomical data are truly Big Data and, in their turn, develop Data Science. Big Data play important role in every field and area, and they are especially important in Science, particularly in Astronomy, as they provide vast amount of information coming from the Universe, useful for many science disciplines (in fact, for all natural sciences and not only). I will review most important historical and modern astronomical surveys, derived from them catalogs, archives and MW databases that are serving as a source for new discoveries based on the combination of various observations. Some of the future large surveys will also be described. An overall picture of Big Data in MW astronomy will be presented and analyzed and possibilities for MW research will be discussed based on the available data at different wavelengths, including building and analyzing of Spectral Energy Distributions (SEDs). A new discipline has appeared, Astroinformatics, which includes Astrostatistics, Simulations, Modeling, Machine Learning, Deep Learning, Active Learning, Virtual Observatories (VOs), etc. A special emphasis will be given to the VOs and their developments.

Stars, the fundamental building blocks of the Universe, undergo multiple stages of evolution throughout their lifecycle. The developmental pathway of stars is both fascinating and complex, continuously attracting research interest. Despite numerous studies, our understanding of star formation is still marked by significant gaps, with more unanswered questions than confirmed theories. This lecture focuses on young stellar objects (YSOs), stars in the initial stages of evolution. This critical phase lasts about 10 million years—a brief period in a star's life, yet crucial for its formation. Most stars originate within dark molecular clouds located in the galactic disk. However, these clouds are often remote, posing challenges in distinguishing YSOs from the multitude of other stellar objects along the line of sight. YSOs feature complex structures, including circumstellar disks and envelopes composed of gas and dust, which contribute to an infrared excess. Therefore, the infrared excess is a crucial observational characteristic of YSOs, serving as a key metric for classifying their evolutionary stages—from the early protostars to the more developed pre-main sequence (PMS) objects. The lecture will explore the primary methods for identifying YSOs and determining their key properties such as mass, evolutionary stage, and age, using solely photometric data.