Aspects Of Astronomy Research Articles

Astronomical Aspects of the Origin and Development of Life

Astronomical Aspects of the Origin and Development of Life

The Twisting of Radio Waves in a Randomly Inhomogeneous Plasma

Polarization of electromagnetic waves carries a large amount of information about their astrophysical emitters and the media they passed through, and hence is crucial in various aspects of astronomy. Here we demonstrate an important but long-overlooked depolarization mechanism in astrophysics: when the polarization vector of light travels along a nonplanar curve, it experiences an additional rotation, in particular for radio waves. The process leads to depolarization, which we call “geometric” depolarization (GDP). We give a concise theoretical analysis of the GDP effect on the transport of radio waves in a randomly inhomogeneous plasma under the geometrical optics approximation. In the case of isotropic scattering in the coronal plasma, we show that the GDP of the angle of arrival of the linearly polarized radio waves propagating through the turbulent plasma cannot be ignored. The GDP effect of linearly polarized radio waves can be generalized to astrophysical phenomena, such as fast radio bursts and stellar radio bursts, etc. Our findings may have a profound impact on the analysis of astrophysical depolarization phenomena.

Studi Komparasi Konsep Kalender Hijriyah Global Tunggal (KHGT) Muhammadiyah dan Kriteria Neo Mabims di Indonesia

Differences in the determination of the beginning of the Hijri month is still a phenomenon that often occurs in Indonesia. This situation is increasingly complex with Muhammadiyah's decision to switch from the Wujudul Hilal method to the Single Global Hijri Calendar (KHGT) system at the beginning of 1446 AH. This research examines the comparison between KHGT and the Neo MABIMS criteria used by the Indonesian Ministry of Religious Affairs, in terms of fiqh and astronomical perspectives. This research attempts to answer two main questions: (1) How is the comparison of KHGT and Neo MABIMS criteria in terms of fiqh and astronomy? (2) What are the implications of the application of these two methods for the determination of the beginning of the Hijri month in Indonesia? Through a qualitative approach with comparative analysis, this research integrates data from ephemeris calculations, KHGT Muhammadiyah, and fiqh studies based on the book Fiqhul Islami wa Adillatuhu. The results reveal fundamental differences in the parameters used: KHGT applies global matlak with a requirement of 8° elongation and 5° hilal height, while Neo MABIMS uses matlak wilayatul hukmi with a parameter of 3° height and 6.4° elongation. This difference has implications for KHGT's tendency to set the beginning of the month earlier, which has the potential to affect the determination of Islamic holidays. However, the fiqh analysis shows that both methods have a foundation that can be accounted for in the perspective of Islamic law. This study recommends the importance of continuous dialogue between various parties to reach a broader agreement in the determination of the Hijri calendar in Indonesia, by comprehensively considering fiqh and astronomical aspects.

Diurnal and Seasonal Variations of Meteor Speed and Arrival Angle Observed by Mengcheng Meteor Radar

AbstractMeteor speed is crucial in identifying key astronomical aspects of the meteoroid environment, including the influx of meteoric material and the distribution of meteoric radiants. This study investigates diurnal and seasonal variations of meteor speed from April 2014 to December 2023 observed by the Mengcheng meteor radar (MCMR; 33.4°N, 116.3°E). In addition to the expected diurnal variation of meteor speed, azimuth peak, zenith peak, and the azimuthal direction of maximum meteor speed due to the Earth's rotation, where the meteor speed peaks northward in the local morning and shifts clockwise, we find that the meteor speed distribution resembles a superposition of two Gaussian distributions, with the lower (higher) distribution mainly ranging from 20 to 40 (45–65) km/s. The two speed peaks are estimated using a double‐Gaussian fitting approach. In terms of seasonal variation, we find that (a) the low‐speed peak indicates a semi‐annual variation cycle, with maxima in June–July and December–January, and minima in February and August; (b) the high‐speed peak indicates an annual variation cycle, with maxima in September–December and minima in March. There is also a correlation between the seasonal variations in the meteor speed peaks and the occurrence of meteor showers. Statistical analysis provides a map of seasonal variations in the intensity, duration, and timing of meteor shower activities, which is supplemental to previous shorter‐duration studies using backscatter meteor radar observations. We also find notable shower events where the meteor counts exceed 45%–97% of the background count on corresponding event dates and speeds.

Astronomical Aspects of the Early Determination of Subuh

Astronomical Aspects of the Early Determination of Subuh

Analysis of Qicblat Direction at Jami Al Iman Mosque Sunan Geseng Loano Purworejo

This research is motivated by the questions from the community around the mosque about the Qibla direction's accuracy and the early history of purchasing the Qibla direction. This study examines the historical and astronomical aspects so that the community can accept the calculation of the Qibla direction. Does this research focus on how before shopping towards the Qibla of the Jami' Al-Iman Sunan Geseng Loano Mosque? How accurate? This empirical research uses historical and astronomical or astronomical approaches. The research subjects were mosque takmir and community leaders in Loano Purworejo. Data were collected through observation, interviews, and documentation and analyzed through astronomy and normative. The results of this study indicate that the Jami' Al-Iman Sunan Geseng Loano Mosque was founded by Sunan Geseng in 1443 AD, using the supernatural through the media of the priest's hole to determine the Qibla direction.

Transfer of Rocks Between Planetary Systems: Panspermia Revisited.

Motivated by the recent discovery of interstellar objects passing through the solar system, and by recent developments in dynamical simulations, this article reconsiders the likelihood for life-bearing rocks to be transferred from one planetary system to another. The astronomical aspects of this lithopanspermia process can now be estimated, including the cross sections for rock capture, the velocity distributions of rocky ejecta, the survival times for captured objects, and the dynamics of the solar system in both its birth cluster and in the field. The remaining uncertainties are primarily biological, that is, the probability of life developing on a planet, the time required for such an event, and the efficiency with which life becomes seeded in a new environment. Using current estimates for the input quantities, we find that the transfer rates are enhanced in the birth cluster, but the resulting odds for success are too low for panspermia to be a likely occurrence. In contrast, the expected inventory of alien rocks in the solar system is predicted to be substantial (where the vast majority of such bodies are not biologically active and do not interact with the Earth).

ASTRONOMY AND THE KOFUN BURIAL MOUNDS OF JAPAN

In Japan there are many burial mounds called Kofun, the graves of ancient kings, emperors, local rulers and their clans, which are scattered throughout Honshu (the main island of Japan) and the islands of Kyushu and Shikoku. This short communication was written in response to a paper by Baratta et al. (2022) that was published in a remote sensing journal, and is designed to outline the contents of their paper in relation to recent Japanese studies of the astronomical aspects of Kofun design.

Augmented reality mobile application to improve the astronomy teaching-learning process

It is during the primary education stage that children begin to awaken their interest in science and, in turn, have new mathematical, geographical, and scientific knowledge, which are the basis for understanding astronomical aspects. This research focuses on developing an Augmented Reality Mobile Application based on the Mobile-D methodology for the teaching-learning process of astronomy in 4th and 6th grade students. The random selection design of an experimental group applied to a sample of 60 students was used, subdivided into groups of 30 students each. Finally, it can be concluded that the use of an Augmented Reality mobile application for the teaching-learning process significantly influences elementary school students in the subject of astronomy.

Astronomical aspects of Group E-type complexes and implications for understanding ancient Maya architecture and urban planning.

In the 1920s, during the first archaeological excavations at Uaxactún, Petén, Guatemala, an architectural complex named Group E was interpreted as an ancient Maya astronomical observatory, intended specifically for sighting the equinoctial and solstitial sunrises. In the following decades, a large number of architectural compounds with the same configuration have been found, most of them in the central lowlands of the Yucatan peninsula. The multiple hypotheses that have been proposed about the astronomical function of these complexes, commonly designated as E Groups, range from those attributing them a paramount role in astronomical observations to those that consider them merely allegorical or commemorative allusions to celestial cycles, without any observational use. This study, based on quantitative analyses of a reasonably large sample of alignment data, as well as on contextual evidence, shows that many of the previous hypotheses cannot be sustained. I argue that E Groups, although built primarily for ritual purposes, were astronomically functional, but also that they had no specific or particularly prominent role in astronomical observations. Their orientations belong to widespread alignment groups, mostly materialized in buildings of other types and explicable in terms of some fundamental concerns of the agriculturally-based Maya societies. I present the evidence demonstrating that the astronomical orientations initially embedded in E Groups, which represent the earliest standardized form of Maya monumental architecture and whose occurrence in practically all early cities in the central Yucatan peninsula attests to their socio-political significance, were later transferred to buildings and compounds of other types. Therefore, it is precisely the importance of the astronomically and cosmologically significant directions, first incorporated in E Groups, that allows us to understand some prominent aspects of ancient Maya architecture and urbanism.

Indigenous Knowledge about Time-Keeping: Astronomical Aspects of The Batak Calendar

The Batak calendar year is often referred to in literature as a lunar year. However, the Batak calendar system reveals that it is set up to compensate for the difference between the lunar year and the solar year. This is of great practical importance insofar as a solar year is primarily useful for planning agricultural work. Nevertheless, they were able to maintain peace and stability within their territorial organizations, called bius, and they were able to organize the co-operation necessary to pursue irrigated rice cultivation. This study is a field research report on an investigation into the subject of the indigenous knowledge of time-keeping, as it was of practical importance to the communal organization of agricultural activities in traditional Toba Batak society. The Batak's time calculation expert calculates, to put it simply, twelve months of thirty days each and calls the remainder of the solar year lobi-lobi ni bulan (the remainder of the month) or lamadu, which makes the lunar and solar years congruent again. As far as is known, the years themselves were not counted in Batak culture, or, if so, only to a limited extent, but the days of the year were counted. Usually there was always at least one specialist in time calculation within a bius organization, because the reliable determination of time was essential to the ritual as well as to the agricultural course of the year.

How the astronomical aspects of climate science were settled? On the Milankovitch and Bacsák anniversaries, with lessons for today

It was 100 years ago (on August 7, 1920), that the comprehensive mathematical foundations of climate change research, written by a Serbian researcher, Milutin Milankovitch, were published. A later interpreter and developer of his results, Georg (in Hungarian: György) Bacsák (Pozsony/Pressburg/Bratislava, June 5, 1870 - Fonyód, March 4, 1970) was born 150 years ago and died at the age of one hundred, half a century ago. In this commemorative paper we look back to special circumstances in revealing the secrets of ice ages that had puzzled scientists for at least several centuries. Recently, after 100 years, the Milankovitch theory, including related short-term forcings (ranging from interannual, multidecadal to millennial timescales) has not only been confirmed, but its climate forcing mechanism has also been identified and proposed. Owing to the uniqueness of the problem, the science of the orbital forcing of climate change can be proclaimed to be essentially settled.

KAJIAN FAKTOR PSIKOLOGI YANG BERPOTENSI MEMPENGARUHI KEBERHASILAN RUKYAT

The success factor in hilal is not only related to astronomical aspects. However, it is also closely related to perukyat’s psychological itself. In psychology, experience is one aspect studied as a scientific study of behavior and mental processes. Psychology uses a systematic method to observe human behavior and draw conclusion from this observation. Some psychological aspects of the perukyat are vision, perception, attention, concentration, and experience. Thorndike's law effect theory states that if an action is followed by a satisfactory change in an environment, the possibility of that action to be repeated tends to increase. That experience is an ability to decide on something because of the knowledge that has been obtained previously. In everyday human life, human experience always forms a unity in certain patterns and configurations. The rukyat technique used by Inwanuddin is in line with psychological theories, namely rukyat before ghurub which aims to increase concentration, then many experiences also affect the subsequent results of rukyat. Some levels of experience obtained based on the data and results of the interval class calculation are: 1-5 times is less experienced, 6-10 times sufficient experience, 11-15 times experienced, 16-20 times very experienced.

IBSE-Type Astronomy Projects Using Real Data

AbstractI present three examples of IBSE (Inquiry-Based Science Education) type activities for students and teachers using data and resources from the Faulkes Telescope Project and the National Schools’ Observatory. Both projects have recently celebrated their 15th anniversary and both provide free access via the internet to 2-metre robotic telescopes to educational users throughout the World. Each activity contains supporting material and sample datasets in several aspects of astronomy as well as instructions on how to analyse data. These activities are designed to be ‘teacher-free’, extended projects for students.They include the study of open clusters via astronomical images and population studies of exoplanets. I also present a Citizen Science project using data from Type Ia supernovae as discovered by the Gaia Alerts consortium. These data allow citizen scientists to develop their own Hubble Plot and begin to understand the link between Type Ia supernovae and the age of the Universe.

COPÉRNICO E A TEORIA HELIOCÊNTRICA: CONTEXTUALIZANDO OS FATOS, APRESENTANDO AS CONTROVÉRSIAS E IMPLICAÇÕES PARA O ENSINO DE CIÊNCIAS

This work is the result of a historiographical study based both on the works of historians of Science and on a translation of Nicholas Copernicus's Commentariolus. Within Science Teaching, the work is justified by the need of discussions that encompass something more than Copernicus's proposition about heliocentrism. Thus, the general objective is to present a broader view on the construction, defense and dissemination of the work of Nicholas Copernicus, contextualizing the time he lived and interpreting the astronomical, philosophical and social aspects that could have influenced his theory. As a result, it can be emphasized that Copernicus counted with the contribution of several astronomers for the elaboration and dissemination of the Copernican System, was influenced by the social, cultural and philosophical context, as for example some Neoplatonic principles, and initially idealized issues were not solved by means of the proposed system, namely: the initial idea of simplification of the Ptolemaic System, with the reduction of the number of epicycles. Finally, it becomes possible to glimpse some implications for Science Teaching, such as the possibility of articulation between the History of Science, the nature of Science and the scientific work and the text to contribute as a subsidy to a teaching by research methodology.

Practical Astronomy Education at the National University of Singapore (NUS)

Singapore is not known for astronomy research. However, the interest in astronomy has grown since the 1990s, when more educational institutions and observatories were built to equip students with the skills and knowledge in astronomy. The National University of Singapore (NUS) currently has a strong and rigorous astronomy and astrophysics programme that leads to an astrophysics specialization within the physics B.Sc. degree as well as four general education modules in astronomy and astrophysics. As experimental data is the final arbiter of any scientific theory, we emphasize the practical aspects of astronomy in this programme. We also have a state-of-the-art observatory equipped with a robotic telescope and a planetarium for tutorials. This paper outlines the philosophy, pedagogy and approach of how our NUS team has achieved a very successful undergraduate astronomy and astrophysics for aspiring Singaporean youth.

Risk-Informed Approach to Mitigation of Asteroid and Comet Impact Hazard. Astronomical Aspects

Risk-Informed Approach to Mitigation of Asteroid and Comet Impact Hazard. Astronomical Aspects

Localization of binary neutron star mergers with second and third generation gravitational-wave detectors

The observation of gravitational wave signals from binary black hole mergers has established the field of gravitational wave astronomy. It is expected that future networks of gravitational wave detectors will possess great potential in probing various aspects of astronomy. An important consideration for successive improvement of current detectors or establishment on new sites is knowledge of the minimum number of detectors required to perform precision astronomy. We attempt to answer this question by assessing ability of future detector networks in detecting and localizing binary neutron stars mergers in the sky. This is an important aspect as a good localization ability is crucial for many of the scientific goals of gravitational wave astronomy, such as electromagnetic follow-up, measuring the properties of compact binaries throughout cosmic history, and cosmology. We find that although two detectors at improved sensitivity are sufficient to get a substantial increase in the number of observed signals, at least three detectors of comparable sensitivity are required to localize majority of the signals, typically to within around 10 deg$^{2}$ --- adequate for follow-up with most wide field of view optical telescopes.

ONE FROM THE EAST, ONE FROM THE WEST: THE UNEASY ENCOUNTERS BETWEEN HONG TAE-YONG AND AUGUSTIN HALLERSTEIN IN MID-EIGHTEENTH CENTURY BEIJING

There were encounters between Chosŏn 朝鮮 scholar Hong Tae-yong 洪大容 (1731– 1783) and Jesuit missionary Ferdinand Augustin von Hallerstein (1703–1774), whose Chinese name was Liu Songling 劉松齡 at the South Church (Nantang 南堂) in Beijing on the 9th day of the 1st month of 1766. Hong Tae-yong, who wanted to learn advanced Western technology, met Hallerstein personally three times and asked him about various aspects of astronomy, Western technology, musical instruments, and Catholicism. He recorded these encounters in classical Chinese in one of the chapters of Tamhŏn yŏn’gi 湛軒燕記 (Hong Tae-yong’s record of an embassy to Beijing), entitled “Yu P’o mundap” 劉鮑問答 (Questions and answers with Hallerstein and Gogeisl). He also recorded these encounters in vernacular Korean in his Ŭlbyŏng yŏnhaengnok 乙丙燕行錄 (Record of an embassy to Beijing in 1765–1766). This study discusses how Hallerstein’s and Gogeisl’s names came to be recorded on the two red papers used to accept Hong’s request for the visit, and further analyzes the historical context related to the red papers. This study also introduces Hallerstein’s letter concerning Chosŏn and attempts to evaluate the encounter between Hong Tae-yong and Hallerstein. Ultimately, in explaining how the background and surroundings of that time made it difficult for their relationship to develop in a constructive way, this study tries to shed light on one case of important interactions between Chosŏn and the West.

“Einstein’s Playground”: An Interactive Planetarium Show on Special Relativity

The understanding of many aspects of astronomy is closely linked with relativity and the finite speed of light, yet relativity is generally not discussed in great detail during planetarium shows for the general public. One reason may be the difficulty to visualize these phenomena in a way that is appropriate for planetariums; another may be their distance from everyday experiences that makes it hard for audiences to connect with the presentation. In this paper, we describe an effort to visualize special relativity phenomena in an immersive “everyday” scenario. In order to bring special relativity to human scale, we simulate a universe in which the speed of light is slower, so that “everyday” speeds become relativistic. We describe the physics and the technical details of our first planetarium show, “Einstein’s Playground,” which premiered at the Museum of Science, Boston.