Astronomical Information Research Articles

An Astronomical Interpretation of a Small Example from Armenian Folklore

This article examines an individual fragment of Armenian folklore about the Aratsani (Euphrates) River from an astronomical perspective, focusing on the central characters - the dragonfish and the bear. Through this analysis, a wealth of “astronomical knowledge” rooted in ancient mythological perceptions is revealed. Specifically, the mentioned figures in the sky correspond respectively to the modern constellations of the Southern Fish (Piscis Austrinus) and the Great Bear (Ursa Major).The described scenes are correlated with the heliacal rising and setting of the main star of Southern Fish constellations. Furthermore, all defining characteristics of the figures are given precise astronomical and mythological interpretations. The legend also highlights expressions related to the unfolding time, which are thoroughly explained based on celestial phenomena and ancient Armenian calendrical concepts. It is demonstrated that the described celestial events are associated with a 65–70-day period, referred to in the Protohaykian calendar structure as the “extra-annual period.” Additionally, the legend reveals close calendrical and ritualistic connections with the astronomical context of Fish-shaped Dragon Stones (Vishapakars). The comprehensive astronomical analysis enables the dating of the legend described to 18800 BC. This serves as a small but striking example of how folklore can act as a unique source of rich astronomical information․

Towards an astronomical use of new-generation geodetic observations. I. From the correlator to full-polarization images

The current algorithms used for the calibration and analysis of very long baseline interferometry (VLBI) networks that only use linear polarizers (as is the case of the VLBI Global Observing System, VGOS) do not properly account for instrumental and source-intrinsic polarimetry, which can cause errors in geodetic and astronomical products. We aim to develop a calibration pipeline for VLBI interferometers that observe in a basis of linear polarization, as is the case of VGOS. The products from this pipeline can be used to obtain valuable full-polarization astronomical information from the observed sources, and they can be used to potentially improve the geodetic results. We used the algorithm PolConvert to write the correlation products in a basis of circular polarization that is compatible with the standard VLBI calibration procedures. In addition to this, we implemented a wide-band global fringe-fitting algorithm that accounts for dispersive effects (ionospheric delay) and allows us to perform full-polarization imaging of all the observed sources, covering the whole frequency band of VGOS. We present the outcome of our pipeline applied to a global IVS VGOS epoch of observations and show example imaging results in total intensity and polarization. We also discuss issues encountered during the analysis and suggest points of improvement in the VGOS system for an optimum geodetic and astronomical exploitation of this interferometer.

BayeSED-GALAXIES. I. Performance Test for Simultaneous Photometric Redshift and Stellar Population Parameter Estimation of Galaxies in the CSST Wide-field Multiband Imaging Survey

The forthcoming Chinese Space Station Telescope (CSST) wide-field multiband imaging survey will produce seven-band photometric spectral energy distributions (SEDs) for billions of galaxies. The effective extraction of astronomical information from these massive data sets of SEDs relies on the techniques of SED synthesis (or modeling) and SED analysis (or fitting). We evaluate the performance of the latest version of the BayeSED code combined with SED models with increasing complexity for simultaneously determining the photometric redshifts and stellar population parameters of galaxies in this survey. By using an empirical statistics–based mock galaxy sample without SED modeling errors, we show that the random observational errors in photometries are more important sources of errors than the parameter degeneracies and Bayesian analysis method and tool. By using a Horizon-AGN hydrodynamical simulation–based mock galaxy sample with SED modeling errors about the star formation histories (SFHs) and dust attenuation laws (DALs), the simple typical assumptions lead to significantly worse parameter estimation with CSST photometries only. SED models with more flexible (or complicated) forms of SFH/DAL do not necessarily lead to better estimation of redshift and stellar population parameters. We discuss the selection of the best SED model by means of Bayesian model comparison in different surveys. Our results reveal that Bayesian model comparison with Bayesian evidence may favor SED models with different complexities when using photometries from different surveys. Meanwhile, the SED model with the largest Bayesian evidence tends to give the best performance of parameter estimation, which is clearer for photometries with higher discriminative power.

The use of astronomical databases to perform practical work in the process of teaching astronomy

The process of learning astronomy should include such a component as the search for astronomical information, as well as provide conditions under which each student will be able to turn such information into his/her knowledge. That is why an important component of a modern lesson should be the students’ purposeful mastery of the skills of working with information, its search and assessment in terms of compliance with the educational goal, etc. Currently, multimedia educational products, pre-prepared by the teacher with the help of a computer and information from the Internet, are an essential means for creating and satisfying students’ interest in learning in general. An important condition for deepening the interest in learning, and therefore deeper assimilation of knowledge, is not the eyeing of interesting pictures (for example, multimedia presentations), but the individual work of the student to transform information while doing educational tasks. However, the essential thing, in this case, is that, on the one hand, the information arrays have huge volumes, and therefore certain experience is needed to search for specific information, and on the other hand, although they are concentrated in numerous repositories, access to them is often open.

Karakter Serial Animasi Astronomi Berbasis Edutainment Untuk Siswa Sekolah Dasar

Astronomy is one of the derivative subjects of science. The progress of astronomy and other sciences is closely related to the progress of a nation's science and technology. However, there are limitations such as the lack of learning facilities that support astronomy learning in schools. In addition, because the subject has many theories and terms, science is a subject that is difficult for students to like or master. Therefore, the animation medium was chosen to introduce astronomy material. To support animation design, it is necessary to design characters as a way of conveying astronomical information. Character design has an important role in conveying storylines and messages to the target audience. This design uses two research methods, namely qualitative and quantitative methods. For qualitative methods, competitor and comparator analysis, in-depth interviews, photo studies, and literature studies are used. As for the quantitative method, a research strategy was used in the form of distributing questionnaires to the target audience of elementary school students. The media output that will be designed is astronomy educational animation with an edutainment approach. The concept of the characters designed is social diversity in accordance with the motto of the Indonesian nation, Bhinneka Tunggal Ika.
 Keyword - Animation, Education, Astronomy, Character Design, Elementary School

Data science methodology for time-delay estimation and data preprocessing of the time-delay challenge

ABSTRACT The vast amount of astronomical information that has become available over this decade has far exceeded that of the last century. The heterogeneity of the data and its overwhelming magnitude have made it impossible to perform manual analysis. As a consequence, new techniques have been developed and different strategies have been amalgamated, such as data science and data mining, in order to carry out more in-depth and exhaustive analyses in search of the extraction of the knowledge contained in data. This paper introduces a data science methodology that consists of successive stages, with the core of this proposal being the step of data preprocessing, with the aim of reducing the complexity of the analysis and enabling hidden knowledge in the data to be uncovered. The proposed methodology was tested on a set of data consisting of artificial light curves that try to mimic the behaviour of the strong gravitational lens phenomenon, as supplied by the Time Delay Challenge 1 (TDC1). Under the data science methodology, diverse statistical methods were implemented for data analysis, and cross-correlation and dispersion methods were applied for the time-delay estimation of strong lensing systems. With this methodology, we obtained time-delay estimations from the TDC1 data set and compared them with earlier results reported by the COSmological MOnitoring of GRAvItational Lenses project (COSMOGRAIL). The empirical evidence leads us to conclude that, with the proposed methodology, we achieve a greater accuracy in estimating time delays compared with estimations made with raw data.

The Physical Parameters, Stability, and Habitability of some Double-lined Spectroscopic Binaries

Large ground telescopes can now resolve most double-lined binaries optically at some point in their orbit due to the improvement of imaging techniques in recent decades. Using additional information about these systems, such as astrometric parallax, even a single precise visual observation can provide a 3D orbit and the primary physical parameters. Furthermore, both the visual and spectroscopic orbits can be determined. We combine the Edward method with the visual solution and the spectroscopic orbit parameters: period (P), periastron epoch (T), eccentricity (e), semimajor axis (a1,2) and inclination (i), we also know the mass ratio of the system. The developed method allows us to select doublelined spectroscopic systems with recently calculated orbits. We calculate the individual masses, orbital parallax, and other fundamental astrophysical parameters. The purpose of these parameters is to verify the reliability of the data received from space missions and to calculate the stability and habitability, which is the primary goal of this study. Astronomical information can be obtained from binary stars. By observing short period binaries using both spectroscopy and interferometry, we can determine the individual masses and orbital parallaxes of the objects based on their corresponding orbits. Spectroscopic binaries with double-lines are therefore fundamentally important to optically resolve. To determine the required telescope aperture for the resolution of a spectroscopic binary, we developed a specific algorithm. Wedetermined the most probable maximum and minimum separations between each spectroscopic binary based on photometric and spectroscopic information. Thus, we also determined the different physical parameters of each system by using the calibrations we obtained in our study. Based on optically resolved spectroscopic binaries with both spectroscopic and visual orbits, the methodology presented here was successfully tested.

Astroinformatics: The Importance of Mining Astronomical Data in Binary Stars Catalogues

The field of Astroinformatics offers exciting new perspectives on astronomical discovery through the implementation of advanced data mining procedures. Data deluges transform research practices and methodologies across various scientific disciplines, including day-to-day astronomical research. It is essential to use innovative algorithms and methods to process astronomical data and its variety. Descriptive Data Mining was used in this study to clarify the importance and effectiveness of obtaining common data between three binary star catalogs. These catalogues are The Ninth Catalogue of Spectroscopic Binary Orbits (SB9), The Sixth Catalog of Orbits of Visual Binary Stars (6COVBS), and The Fourth Catalog of Interferometry Measurements of Binary Stars (4CIMBS). We collect scattered data from the Ninth Catalog in its latest edition in 2021, which contains astronomical information for approximately 4021 binary systems. Then we search for the orbits of these binary systems in the 6COVBS to calculate the physical and the orbital properties with high accuracy. After that, we use the 4CIMBS to look for new observations of these stars in 66,225 resolved stars in its latest edition 2020 to calculate new orbits. As a result of this research, we have found about 600 standard systems among these catalogues, which are valuable data to calculate many physical properties of such binary stars, starting from individual masses, by the combination of the spectroscopic orbital solution with the visual orbital solutions. Furthermore, calculate the orbital parallax for each system with high accuracy compared with those from space missions such as Gaia and Hipparcos give us a new and essential method to verify the validity of the data from those satellites.

Youth project Space-π using small spacecraft for research of near-Earth space and remote sensing of the earth

One of the promising areas of research applicable in astrophysics is the study of the properties of quantum dots (QDs) and quantum wells (QWs) in the IR region of the spectrum. The IR region of the spectrum contains a huge amount of astronomical information. Devices based on GaAs/AlGaAs QWs and Ge/Si QDs can serve as detectors and sources of IR radiation. In the current work, the photoluminescence, absorption, and transmission spectra of these nanoheterostructures were obtained in the near, mid, and far IR ranges using Fourier spectroscopy. Thus, the studied optical properties of QWs and QDs make it possible to use these structures in astrophysics as sources and detectors of IR radiation.

Detectors for space electronics based on the quantum dots and wells

One of the promising areas of research applicable in astrophysics is the study of the properties of quantum dots (QDs) and quantum wells (QWs) in the IR region of the spectrum. The IR region of the spectrum contains a huge amount of astronomical information. Devices based on GaAs/AlGaAs QWs and Ge/Si QDs can serve as detectors and sources of IR radiation. In the current work, the photoluminescence, absorption, and transmission spectra of these nanoheterostructures were obtained in the near, mid, and far IR ranges using Fourier spectroscopy. Thus, the studied optical properties of QWs and QDs make it possible to use these structures in astrophysics as sources and detectors of IR radiation.

“I Counted Sun’s Faces” in the Short Recension of 2 Enoch

Abstract 2 Enoch without any doubt is one of the most interesting and enigmatic texts of Slavonic Pseudepigrapha. Since the publication of the first fragments of it in the middle of the 19th century, there has been a protracted debate on all the questions concerning the history of the pseudepigraphon. And the “astronomical information” in it is possibly one of the most mysterious parts of 2 Enoch. The contents of the two main recensions are quite different in the chapter dealing with astronomical material. The paper studies the fragment, in which, in the short recension, it is literally said: “I [Enoch] counted Sun’s faces”.

"Temple complexes" in the religious life of the trypillia community

In the period 4800-3600 BC. in the eastern part of the Trypillia area arose "giant settlements" or "megasites" / "mega-settlements" (working term of modern archaeologists) with thousands of buildings. In the central parts of these living conglomerates, scientists found special buildings that were recognized as sanctuaries, sacred complexes or temples. In the late period of the Trypillia culture they disappeared. These religious buildings were built with a focus visible processes of celestial bodies and the laws of cyclic rotation of the Earth in space, and included in their internal filling usually cruciform altars, ritual utensils, troughs with graters for the preparation of ritual bread and numerous other ceremonial and religious artifacts. There were also unique finds, such as gold jewelry (an element of prestige) and a perforated clay disk with tockins to it from the space of the Nebelivka Temple. The interior and exterior walls of the Trypillia sacral centers were painted with natural colors with a predominance of red. The wood carving for decoration of elements of a skeleton of a construction was investigated also. The first Temples on the European continent show that even at that time there was a cult of architecture. In general, it is clear that such Trypillia objects of religious worship carried encoded astronomical information in symbolic form. The building itself was oriented with regard to worldsides and designed relative to visible celestial bodies. This indicates that the people of Trypillia had a fairly clear worldview, which allowed them to reach the level of understanding the structure and mechanisms of many natural cyclical processes on Earth. Trypillia cosmology united the celestial and terrestrial spheres, and the Temple was the point of contact of the earth with the visible Universe.
 In his work, the author traces the existing analogies in the structure of construction of Trypillia and sacred complexes of the ancient Middle East and biblical ideas about the Tabernacle and the House of the Lord in the ancient Jews, given the fact, that the Trypillia temple building is known from 4,000 years BC. and several thousand years older than the Middle Eastern counterparts. There are also significant parallels in the construction of temples in the context of Indo-European religious heritage.
 It is noted that the Temple was not only a metaphysical reflection of the annual cycle with a focus on the points of the equinoxes and solstices, but also had a higher religious function, which consisted in the combination of the terrestrial sphere with the celestial, the connection of man with the mystery of the cosmos.

Radio frequency interference mitigation using pseudoinverse learning autoencoders

Radio frequency interference (RFI) is an important challenge in radio astronomy. RFI comes from various sources and increasingly impacts astronomical observation as telescopes become more sensitive. In this study, we propose a fast and effective method for removing RFI in pulsar data. We use pseudo-inverse learning to train a single hidden layer auto-encoder (AE). We demonstrate that the AE can quickly learn the RFI signatures and then remove them from fast-sampled spectra, leaving real pulsar signals. This method has the advantage over traditional threshold-based filter method in that it does not completely remove contaminated channels, which could also contain useful astronomical information.

A method for unmasking incomplete astronomical signals: Application to the CO Multi-line Imaging of Nearby Galaxies project

ABSTRACT Photometric surveys have provided incredible amounts of astronomical information in the form of images. However, astronomical images often contain artifacts that can critically hinder scientific analysis by misrepresenting intensities or contaminating catalogs as artificial objects. These affected pixels need to be masked and dealt with in any data reduction pipeline. We present a flexible, iterative algorithm to recover (unmask) astronomical images where some pixels are lacking. We demonstrate the application of the method on some intensity calibration source images in the CO Multi-line Imaging of Nearby Galaxies (COMING) project conducted using the 45 m telescope at Nobeyama Radio Observatory. The proposed algorithm restored artifacts due to a detector error in the intensity calibration source images. The restored images were used to calibrate 11 out of 147 observed galaxy maps in the survey. The tests show that the algorithm can restore measured intensities at sub 1% error even for noisy images (S/N = 2.4), despite lacking a significant part of the image. We present the formulation of the reconstruction algorithm, discuss its possibilities and limitations for extensions to other astronomical signals, and examine the results of the COMING application.

The Most Probable 3D Orbit for Spectroscopic Binaries

Abstract Binary stars are a very important source of astronomical information. Those short-period binaries observed by means of both spectroscopy and interferometry can provide, through their corresponding orbits, precise values regarding individual masses as well as orbital parallaxes. For this reason, it is fundamental to attempt to optically resolve double-lined spectroscopic binaries. In the present article, we used the elaboration of a specific algorithm in order to determine the necessary telescope aperture to resolve a concrete spectroscopic binary. To that end, using available photometric and spectroscopic information, we established a 3D model for each spectroscopic binary with an orbit from which we deduced the most probable maximum and minimum separations between the components. In this manner, using the obtained calibrations in our study, we also deduced different physical parameters of the components of each system. The methodology presented here was tested satisfactorily with a list of spectroscopic binaries that had been optically resolved and that have both the spectroscopic and visual orbits.

Archaeoastronomy in the Big Data Age: Origin and Peculiarities of Obtaining Data on Objects and Artifacts

AbstractThe impressive transition from an era of scientific data scarcity to an era of overproduction has become particularly noticeable in archaeoastronomy. The collection of astronomical information about prehistoric societies allows the accumulation of global data on: – the oldest traces of astronomical activity on Earth, emotional and rational display of celestial phenomena in astronomical folklore, “folk astronomy” and timekeeping, in fine arts and architecture, in everyday life; – the most ancient applied “astronomy” – counting the time by lunar phases, accumulation and storage of ancient databases in drawings and pictographic compositions in caves and artificially constructed objects; – “horizon” astronomy as an initial form of observational cult astronomy, preserved only in characteristic material monuments (the oldest cult observatories) with indisputable astronomical orientations. The report shows the importance of collecting the maximum number of artifacts and monuments from prehistory associated with the early emergence of interest in celestial phenomena. Spiritual, emotional and rational (including practical) needs that have aroused interest in Heaven are discussed. The huge variety of activities in realizing the regularity (cyclicity) of celestial phenomena as a stimulus for their use for orientation in space and time is shown.

The IAU Strategic Plan 2020–2030, a blueprint for forging a new social revolution in astronomy and for using astronomy as a tool for building a progressive society

AbstractI discuss the second IAU Strategic Plan for the decade 2020–30 in the context of the overall evolution of the IAU in recent past decades. This article shows how the IAU has evolved dramatically since WW2. It is hardly recognizable in terms of its original organization and goals of a century ago. What was once an inward-looking body engaged purely with the procedures of astronomical research is now a dynamic and outward-looking organization, interacting with people, especially students and the public.A large part of this success must be attributed to the IAU’s unique body of individual members, whose number has grown strongly in recent decades. It is the individual members, especially through the Commissions and Working Groups, who have promoted these enormous changes in the outlook of the Union. This is a model for other scientific unions to follow, and especially for the work to promote the careers of women in science, for promoting the careers of young astronomers, for bringing students into astronomy or into science in general, for helping people with disabilities to have careers in astronomy, for engaging with the public, and for helping to develop astronomy and science in developing countries.Looking to the future, the IAU’s new Strategic Plan for the years 2020 to 2030 has five major goals for the coming decade: 1. The IAU leads the worldwide coordination of astronomy and the fostering of communication and dissemination of astronomical knowledge among professional astronomers. 2. The IAU promotes the inclusive advancement of the field of astronomy in every country. 3. The IAU promotes the use of astronomy as a tool for development in every country. 4. The IAU engages the public in astronomy through access to astronomical information and communication of the science of astronomy. 5. The IAU stimulates the use of astronomy for teaching and education at school level.Future developments will also be engaging with the large number of amateur astronomers and helping to promote astro-tourism, which is perhaps the new frontier now growing rapidly around the world. The Strategic Plan is a blueprint for forging a social revolution in astronomy and for using astronomy as a tool for building a progressive society.

A HISTORY OF WESTERN ASTRONOMICAL ALMANACS

Astronomical data were the basis for calendars, time, phenomena predictions, and theories about the universe from the earliest days. Knowledge developed independently in different countries and then was exchanged when international trading developed. There was an apparent lack of development of knowledge during the middle ages. Then at the reformation period a new increase in theories, observations, and knowledge developed. The advent of the printing press brought the availability of almanacs in large numbers for everyday use. The requirements of calendars, navigation, and astronomical information led to national almanacs and improved accuracies. The need for standards for reference systems, including ephemerides, time scales, astronomical constants, and star catalogs led to international cooperation. New technologies, computers, and the space age led to improved accuracies and new reference systems. Calculators and computers led to new methods of access to almanac data, including data online.

Celestial mechanics and polarization optics of the Kordylewski dust cloud in the Earth–Moon Lagrange point L5 – Part II. Imaging polarimetric observation: new evidence for the existence of Kordylewski dust cloud

Telescopes mounted with polarizers can study the neutral points of the Earths atmosphere, the solar corona, the surface of planets/moons of the Solar System, distant stars, galaxies and nebulae. These examples demonstrate well that polarimetry is a useful technique to gather astronomical information from spatially extended phenomena. There are two enigmatic celestial objects that can also effectively be studied with imaging polarimetry, namely the Kordylewski dust clouds (KDCs) positioned around the L4 and L5 triangular Lagrangian libration points of the Earth-Moon system. Although in 1961 the Polish astronomer, Kazimierz Kordylewski had observed two bright patches near the L5 point with photography, many astronomers assume that these dust clouds do not exist, because the gravitational perturbation of the Sun, solar wind and other planets may disrupt the stabilizing effect of the L4 and L5 Lagrange points of the Earth and Moon. Using ground-born imaging polarimetry, we present here new observational evidence for the existence of the KDC around the L5 point of the Earth-Moon system. Excluding artefacts induced by the telescope, cirrus clouds or condensation trails of airplanes, the only explanation remains the polarized scattering of sunlight on the particles collected around the L5 point. By our polarimetric detection of the KDC we think it is appropriate to reconsider the pioneering photometric observation of Kordylewski. Our polarimetric evidence is supported by the results of simulation of dust cloud formation in the L5 point of the Earth-Moon system presented in the first part of this paper.

Star Recognition Based on Path Optimization in Star Sensor with Multiple Fields of View

Star sensors make use of astronomical information in stars to determine attitude for spacecrafts by star image recognition. For low-cost star sensors with small field of view, fusion of observed images from multiple fields of view is performed and a novel recognition algorithm based on path optimization by randomly distributed ant colony is proposed. According to pheromone intensity, the ant colony can autonomously figure out a close optimal path without starting or ending point, rather than certifying a starting point first. Feature patterns extracted from the optimal path in guiding template and observed image after fusion are compared to perform star recognition. By the proposed algorithm, starting point for path optimization has no influence on the extracted feature pattern. Thus the star recognition rate is improved due to the higher stability of the extracted pattern. Simulations indicate that the algorithm improves recognition accuracy and robustness against noise for sensors with multiple fields of view.