The Armenian highland is one of the ancient cradles of civilization. Many investigators of the history of astronomy, having no facts to hand, mainly by logical approach came to the conclusion that the ancient inhabitants of Armenia not only knew, but also took part in the formation of ancient astronomy (Maunder, 1906; Olcott, 1914).

Review is devoted to estimators introduced in astronomy by Ambartsumian and his followers that are used to estimating the unknown number of flare stars and other randomly flashing objects (stars with X-ray flares, solar type stars with superflares). Some important astronomical applications of them are presented. The development of these methods in astronomy have proceeded regardless of development of analogous methods of mathematical statistics. Brief history of this development and parallels with similar statistical methods is presented.

The problem of the origin of Life is discussed from the astrophysical point of view. Most biologists and geologists up to the present time believe that Life was originated on the Earth in some initial natural chemical pre-reactors, where a mixture of water, ammonia, methane containing species and some other substances, under the influence of an energy source like, e.g. lightning, turned into quite complex compounds such as amino acids and complex hydrocarbons. In fact, under conditions of the primordial Earth, it is not possible to obtain such pre-biological molecules by not-bio-chemical methods, as discussed in this paper. Instead, an astrophysical view of the problem of the origin of Life on the Earth is proposed and it is recalled that the biological evolution on the Earth was preceded by the chemical evolution of complex chemical compounds, mostly under extraterrestrial conditions, where it is only possible to form optically active amino acids, sugars and heavy hydrocarbons necessary for constructing the first pre-biomolecules. Then, according to a widespread point of view, they were brought to Earth by comets and dust between 4.5 and 3.8 billion years ago. Some part of the matter of comets landed unchanged during grazing collisions. Prebiotic complexes on the surface of the planet participate in the formation of a specific cover with a reflective spectrum (or color index), whose characteristic details can be tried to reveal by observation. The most promising bio-indicators at present are optically active amino acids and their derivatives, however, the existing observational capabilities are insufficient to identify them. More promising as (pre)biomarkers are the heavy hydrocarbons discussed in this article, in particular bitumen and isoprene hydrocarbons.

One of the main observational properties of young stellar objects in the optical range is the presence of emission lines, in particular H (6563 Å). Therefore, detection of H emission is the most common spectroscopic means for identification of young stars. The paper presents the results of searching and studying of young stellar objects in several star forming regions carried out on the 2.6 m telescope in Byurakan observatory. The quantitative relationships between objects with different stage of activity are considered. In addition, a statistical analysis of H activity and other manifestations of PMS activity (X-ray, IR excess), as well as an evolutionary age of the H emitters in several star-forming regions is provided.

High-luminosity IR galaxies (LIRGs, ULIRGs, and HLIRGs) are important for studies related to star-formation processes in the early Universe, as their luminosity allows to detect them at large distances. High IR indicates active star-formation and often starburst processes, which is typical to HII (starburst, SB) and AGN. An interesting question is whether the starburst triggers AGN or vice versa or there is no direct impact. Considering that very often such objects manifest double and multiple structure, it is also interesting to investigate the interrelationship between the SB, nuclear activity and interactions or merging. We have analyzed the IRAS PSC/FSC Combined Catalogue for search for new bright ULIRGs. By means of the SDSS DR14 data, namely redshifts for those objects having spectroscopy, we have calculated the IR luminosities and have found 114 very high-luminosity IR galaxies; 107 ULIRGs and 7 HLIRGs. Among them, 48 new ULIRGs and 7 new HLIRGs have been discovered. These objects have been studied by SDSS color-color, luminosity-redshift and other diagrams. Further studies will include the content of the sample for activity types and other available data.