Byurakan Astrophysical Observatory: 75 years of outstanding achievements

The Byurakan Astrophysical Observatory (BAO) is one of the most famous observatories of the Soviet Union and may be of the world. It was founded in 1946 by the outstanding scientist Viktor Ambartsumian (1908-1996) and became the leader of studies on instability phenomena in the Universe. Many discoveries have been carried out at BAO related to stars, star clusters and other systems, nebulae, galaxies and systems of galaxies. BAO has two major instruments; 1m Schmidt and 2.6m classical telescopes. Together with V. Ambartsumian, outstanding scientists Beniamin Markarian, Grigor Gurzadyan, Marat Arakelian and others have worked at BAO. Many important international meetings and schools for young astronomers have been held. Many important people, including State authorities, Nobel Prize Winners and others have visited BAO. BAO has statuses of RA National Value, Regional Astronomical Centre, it has UNESCO Documentary Heritage item, its garden is recognized as Dendrarium, and there is RA National Hero Viktor Ambartsumian's house-museum.

BAO Plate Archive Project: Recent Results

We present the recent results of the Byurakan Astrophysical Observatory (BAO) Plate Archive Project that is aimed at digitization, extraction and analysis of archival data and building an electronic database and interactive sky map. BAO Plate Archive consists of some 37,000 photographic plates and films, obtained with 2.6m telescope, 1m and 0.5m Schmidt telescopes and other smaller ones during 1947-1991 and then by digital methods since 1996. Its most important part, the famous Markarian Survey (or the First Byurakan Survey, FBS) 1874 plates were digitized in 2002-2007 and the Digitized FBS (DFBS, www.aras.am/Dfbs/dfbs.html) was created. New science projects have been conducted based on this low-dispersion spectroscopic material. Several other smaller digitization projects have been carried out as well, such as part of the Second Byurakan Survey (SBS) plates, photographic chain plates in Coma, where the blazar ON 231 is located and 2.6m film spectra of FBS Blue Stellar Objects. However, most of the plates and films were not digitized. In 2015, we have started a project on the whole BAO Plate Archive digitization, creation of electronic database and its scientific usage. Armenian Virtual Observatory (ArVO, www.aras.am/Arvo/arvo.htm) database will accommodate all new data. The project lasted 4 years in 2015-2018. Later on, the project was renovated for 2020-2021. The final result will be an Electronic Database and online Interactive Sky map to be used for further research projects.

Outline of Calendar Studies Conducted at the Byurakan Astrophysical Observatory in 1983-2021

The calendar studies conducted at the Byurakan Astrophysical Observatory in 1983-2021 are the result of Grigor Broutian’s initiation and scientific activity. The approaches used by him have raised a number of new issues and provided extremely important results that are a serious incentive for the future development of this multilayered and multifaceted field in terms of astronomy and historical culture. Almost all the problems of the Armenian and adjacent calendars of the Christian period have been discussed and finally resolved. The Armenian calendar attributed to Hayk Nahapet has been thoroughly researched and brought to an astronomically grounded comprehensive solution. The preliminary, so-called Protohaykian calendar has been revealed with its main and key aspects, and received astronomical as well as archaeological real evidence. All in all, in general the 11,000- year-old Armenian calendar-astronomical traditional historical culture has been deciphered in its continuity. Some new data have been obtained in favor of the existence of an earlier, the so-called “Initial Calendar” as well. Moreover, common close relations have been revealed in the field of natural-philosophical-religious and their historical-cultural-astronomical traditional perception of the creation of the ancient Armenian “Vishap” (“dragon”) stone monuments, the “Zorats Qarer” megalithic ensemble, the “Sasnay Tsrer” (Daredevils of Sassoun) epic poem, the Armenian folk tales and archaeological materials.

Surveys for active galaxies: discovery and studies

We present surveys and related studies of active galaxies carried out at the Byurakan Astrophysical Observatory (BAO). This was one of the main research subjects at BAO during many years, since mid-1950s, when Viktor Ambartsumian suggested the hypothesis of the activity of the galactic nuclei. A number of surveys and searches for Active Galactic Nuclei (AGN) and other active galaxies were accomplished during 1960s-1980s. Since mid-1990s, our research group carried out new surveys and studies of active galaxies based on the First Byurakan Survey (FBS or Markarian Survey) and then a number of others. Here we also present the recent results of studies on active galaxies (both AGN and Starbursts) by the Extragalactic group of the Byurakan Astrophysical Observatory (BAO) Research Department “Astronomical Surveys”. These studies are characterized by multiwavelength approach to statistical analysis of large amount of data obtained in different wavelengths; from X-ray to radio. A fine classification scheme for active galaxies has also been suggested.

Under the Armenian sky-for development and interchange of experiences

The cooperation between two partners: Polish Association Under the common sky and Byurakan Astrophysical Observatory (BAO) was run in 2018/2019. The project based on its leading idea, experience, methodology and knowledge. The Association's fundamental aim is popularization of the cutting-edge knowledge about the Universe as well as teaching skills using modern technology like Stellarium program and telescopes. The future of the project in Armenia depends on schools, teachers and students. They have all the necessary knowledge, skills, equipment and help from the Association as well as BAO to continue their work.

Spectral obervations of flare stars TZ ARI and ROSS 867

The results of spectral observations of flare stars TZ Ari and Ross 867B are presented. Observations have been carried out by the 2.6m telescope of Byurakan Astrophysical Observatory in 1999, 2001 and 2018. The spectral cameras "ByuFOSC" and "SCORPIO" were used during the observations. A strong change of emission lines detected on TZ Ari in 2018, while at the same time the brightness changes of the star in all measured spectral ranges are within the framework of measurement errors. Slight variations of brightness and EWHα are detected in quiescent state of star during the observations in 1999. A strong flare of Ross 867B were observed, with a duration of more than 20min. In this case if EWHα shows strong change, when its maximum value corresponds to the photometric maximum of are, at the same time EWHα shows decrease, similar to that, observed earlier during the flares of stars EV Lac, HU Del, CM Dra and WX UMa.

Space Activities in Armenia: past, present and future

A review about Space related activities in Armenia is given, particularly in the Byurakan Astrophysical Observatory (BAO, Armenia), including the first Space Astronomy projects by Grigor Gurzadian in 1960s-1970s (Orion and Orion-2 UV observatories), research projects with USA (NASA) and European (ESA) Space observatories (IRAS, ROSAT, Hubble, Spitzer, WISE, etc.) by BAO scientists, Armenian participation in International Virtual Observatory Alliance (IVOA), International Planetary Data Alliance (IPDA), and UN Committee on the Peaceful Users of the Outer Space (COPUOS), “Roscosmos” station in Byurakan established in 2014 for monitoring of Space debris, Armenian participation in NASA Space Apps Hackathons, Armenian participation in the European H2020 project, including the Space field, organization of Space related meetings and schools in Byurakan, etc. Armenia with its astronomical and other related background has great potential in establishing collaborations and promoting Space Sciences and Space Technologies.

Studies of Active Galaxies in Byurakan: Recent Results

We present the recent results of studies on active galaxies (both AGN and Starbursts) by the Extragalactic group of Byurakan Astrophysical Observatory (BAO) Research Department “Astronomical Surveys”. The research has been carried out in 2017-2019 and the results are published in 2018-2019. These studies are characterized by multiwavelength approach to statistical analysis of large amount of data obtained in different wavelengths; from X-ray to radio. Results on HRC/BHRC sample objects (optical identifications of ROSAT X-ray sources), studies of Markarian galaxies in UV and multiwavelength SEDs, abundance and star formation determinations in Mrk galaxies from SDSS spectra, revised optical classification of “LINERs”, study and classification of SDSS spectra for Byurakan-IRAS Galaxies, summary of observations and study of Byurakan-IRAS Galaxies (BIG objects), discovery of new bright ULIRGs from the IRAS PSC/FSC Combined Catalogue and their spectral classification, radio variable sources at 1400 MHz and their optical variability, classification of BZCAT objects having uncertain types (BZU objects), and optical variability of blazars are presented.

Search for Galaxies Clusters around Radio Galaxies with Different Linear Sizes

In order to understand how galaxies have formed and evolved in dense environments, and how these environments themselves evolve, we use the method of optical photometric survey of the field around radio galaxies. For this purpose, a statistical significant sample of radio galaxies consisting of 3 size radio source subclasses - GPS, CSS and FRI/II is selected for observations at the 1m Schmidt telescope of the Byurakan Astrophysical Observatory. This method will allow us not only to detect distant clusters of galaxies, but also watch the sequence of development of these clusters - how changes their compactness, richness, and so on.