Lunar Eclipse Research Articles

Astronomy in Hebrew in Istanbul: Abraham ben Yom Ṭov Yerushalmi (fl. 1510)

The only astronomical work by Abraham ben Yom Ṭov Yerushalmi is a set of instructions (or canons) in Hebrew for astronomical tables for which the tables are not extant. Abraham was active in Istanbul in the early sixteenth century and cited many previous authors of astronomical tables in Hebrew. The instructions include ways to use the tables for computing mean and true planetary positions as well as solar and lunar eclipses. According to a prayer book published in 1523, Abraham was familiar with the tables of Ulugh Beg (composed ca. 1440), originally in Persian, and translated into Arabic and Turkish. An anonymous Hebrew version of Ulugh Beg's tables is uniquely preserved in Paris, Bibliothèque nationale de France, MS Heb. 1091. It is noteworthy that Abraham's canons share some unusual technical terms with the Hebrew version.

Critical study of concept of Grahana (Eclipse) in Ayurveda and jyotish science and its influence on human lives WSR to COVID-19

Objective: (1) To intimate about the concepts of Grahana as described in Jyotish Shastra and Ayurveda. (2) Brief knowledge about the facts related to the science of Jyotish for the current scenario. (3) To describe about the impacts of celestial events on human life and on present pandemic, i.e., COVID-19. Data Sources: Secondary. Review Methods: Literary method is adopted here from the available sources of Ayurveda and different Ancient Jyotish (Astrological) texts. Results: From the literature, it is observed that there are definite relations in between the eclipses of Sun and Moon on wars and pandemics. Conclusions: Effects of eclipses on pandemics were seen since a long period of time. It was observed and concluded that eclipse affects the human lives in various ways and may act as potential indicator of war and epidemics. To generate the data, there is a need to study the effects of eclipses on epidemics and wars which in turn has been told as the cause of epidemic in Ayurveda.

Differential Emission Measure Plasma Diagnostics of a Long-Lived Coronal Hole

We use Solar Dynamics Observatory (SDO)/Atmospheric Imaging Assembly (AIA) data to reconstruct the plasma properties from differential emission measure (DEM) analysis for a previously studied long-lived, low-latitude coronal hole (CH) over its lifetime of ten solar rotations. We initially obtain a non-isothermal DEM distribution with a dominant component centered around 0.9 MK and a secondary smaller component at 1.5 – 2.0 MK. We find that deconvolving the data with the instrument point spread function (PSF) to account for long-range scattered light reduces the secondary hot component. Using the 2012 Venus transit and a 2013 lunar eclipse to test the efficiency of this deconvolution, significant amounts of residual stray light are found for the occulted areas. Accounting for this stray light in the error budget of the different AIA filters further reduces the secondary hot emission, yielding CH DEM distributions that are close to isothermal with the main contribution centered around 0.9 MK. Based on these DEMs, we analyze the evolution of the emission measure (EM), density, and averaged temperature during the CH’s lifetime. We find that once the CH is clearly observed in EUV images, the bulk of the CH plasma reveals a quite constant state, i.e. temperature and density reveal no major changes, whereas the total CH area and the photospheric magnetic fine structure inside the CH show a distinct evolutionary pattern. These findings suggest that CH plasma properties are mostly “set” at the CH formation or/and that all CHs have similar plasma properties.

Location, orbit, and energy of a meteoroid impacting the Moon during the lunar eclipse of 2019 January 21

ABSTRACT During lunar eclipse of 2019 January 21, a meteoroid impacted the Moon producing a visible light flash. The impact was witnessed by casual observers offering an opportunity to study the phenomenon from multiple geographical locations. We use images and videos collected by observers in seven countries to estimate the location, impact parameters (speed and incoming direction), and energy of the meteoroid. Using parallax, we achieve determining the impact location at lat.$-29.43^{+0.30}_{-0.21}$, lon.$-67.89^{+0.07}_{-0.09}$, and geocentric distance as 356 553 km. After devising and applying a photometric procedure for measuring flash standard magnitudes in multiple RGB images having different exposure times, we found that the flash, had an average G-magnitude 〈G〉 = 6.7 ± 0.3. We use gravitational ray tracing (GRT) to estimate the orbital properties and likely radiant of the impactor. We find that the meteoroid impacted the moon with a speed of $14^{+7}_{-6}$ km s−1 (70 per cent C.L.) and at a shallow angle, θ < 38.2 deg. Assuming a normal error for our estimated flash brightness, educated priors for the luminous efficiency and object density, and using the GRT-computed probability distributions of impact speed and incoming directions, we calculate posterior probability distributions for the kinetic energy (median Kmed = 0.8 kton), body mass (Mmed = 27 kg) and diameter (dmed = 29 cm), and crater size (Dmed = 9 m). If our assumptions are correct, the crater left by the impact could be detectable by prospecting lunar probes. These results arose from a timely collaboration between professional and amateur astronomers that highlight the potential importance of citizen science in astronomy.

Uncooled microbolometer arrays for ground-based astronomy

ABSTRACT We describe the design and commissioning of a simple prototype, low-cost 10 μm imaging instrument. The system is built using commercially available components including an uncooled microbolometer array as a detector. The incorporation of adjustable germanium reimaging optics rescale the image to the appropriate plate scale for the 2 m diameter Liverpool Telescope. From observations of bright Solar system and stellar sources, we demonstrate a plate scale of 0.75 arcsec per pixel and confirm the optical design allows diffraction limited imaging. We record a ∼10 $\, {\rm per\, cent}$ photometric stability due to sky variability. We measure a 3σ sensitivity of 7 × 103 Jy for a single, ∼0.11 s exposure. This corresponds to a sensitivity limit of 3 × 102 Jy for a 60 s total integration. We present an example science case from observations of the 2019 January total lunar eclipse and show that the system can detect and measure the anomalous cooling rate associated with the features Bellot and Langrenus during eclipse.

PREDIKSI PERGERAKAN BAYANGAN BUMI SAAT TERJADI GERHANA BULAN MENGGUNAKAN EPHEMERIS HISAB RUKYAT

AbstractIn this era, the prediction of lunar eclipse can be determined accurately with the astronomical data based algorithm. Usually, the prediction just compute the position and time of lunar eclipse without considered the movement of Earth shadow in the begginning to the end of eclipse. In this article the author explain how is the concept, algorithm, and analysis about the movement of Earth shadow on going lunar eclipse in certain local coordinate point, using the data from Ephemeris Hisab Rukyat.Keywords : Lunar Eclipse, Earth Shadow, Ephemeris Hisab Rukyat

On the Pre-demonstrative (hoti) Conception of Lunar Eclipse in Posterior Analytics B 8

My aim is to show that, in Posterior Analytics B 8, the conception of lunar eclipse brought about by pre-demonstrative knowledge (hoti) is deeply vague and radically different from the one obtained by demonstrative knowledge (dioti).

Estimating the size of Earth's umbral shadow using sky brightness light curves during a lunar eclipse

We present a simple method to estimate the size of Earth's umbral shadow in a classroom setting. The method uses the published sky brightness curves obtained during a total lunar eclipse and requires only a conceptual understanding of lunar eclipses and simple geometric considerations. It is suitable for use in introductory and upper level astronomy courses.

New Astronomy in Service of Old Astrology: Close Planetary Conjunctions in Pre-Modern China

This article introduces various definitions and criteria for the astronomical phenomena of “encroachments” (close lunar and planetary conjunctions) in pre-modern China. With improvements in observations and mathematical astronomy, the standard of encroachments began to undergo many changes leading to more precise explanations of the phenomena. Before the adoption of Huihui Lifa (Islamic-Chinese calendrical astronomy), traditional Chinese methods could not predict the phenomena of encroachments, and records of encroachments were mainly based on actual observations. These records abound in Chinese dynastic histories, and they play an essential role in the interpretation of astrological omens. In the first half of the seventeenth century, the prediction of encroachments became an effective approach for examining the accuracy of different elements of calendrical astronomy besides solar and lunar eclipses. In the meantime, with the introduction of western astronomical knowledge into China, people had a better understanding of the principle of encroachments, and they began to question its rationality in astrology. Moreover, new knowledge of encroachments also brought new insights and inspired some philosophical discussions on the structure of the cosmos. However, these new astronomical methods still served the old astrology, due to the continued requirements that astronomers interpret astrological omens.

Augmented Reality Applied in Astronomy Subject

Mobile augmented reality is one of the most potential technology for education. Science astronomy is one of the subject that need to develop by mobile augmented reality technology. Purpose in this research is to create mobile augmented reality based on astronomy subject in Indonesian curriculum in junior high school. Animation that has been show in this application follows Kepler’s law about planetary motion. This research is R&D research and it follow instructional design type ADDIE. This researcher collected the data qualitatively from 2 experts, 2 teachers and 2 students. Each of participant will give suggestion to improve the quality of the application. Finally the application has been made with 16 marker. 11 explain about member of solar system, 3 marker about rotation and revolution of earth and moon, and 2 marker is about solar eclipse and moon eclipse. The application size is 47 Mb with Apk format. It can be use at least in android version 4.1 jelly bean and camera 13 MP. This application is ready to use for more large participant.

A Possible Date for Ptolemy’s Development of a Model for the Second Lunar Anomaly

Ptolemy explicitly claims in the Almagest to have made 36 observations. For most of them, the date of the observation is determined by the kind of phenomenon observed, for example, the observation of a lunar eclipse or of an equinox. There are six observations, however, in which a particular date is not required by the nature of the phenomenon under investigation. In five of them, Ptolemy measures the longitude of each planet, without any particular requirement. In the sixth, he measures the longitude of a star. The aim of this paper is to show that these six observations belong to the set of observations that Ptolemy could have used for discovering the second lunar anomaly. Because all of them took place in the first half of year 139, one can presume that it was then when Ptolemy developed his model for the second lunar anomaly.

Pembuatan Aalat Peraga Kiara Payung dalam Pembelajaran Sistem Tata Surya

The props "Kiara Payung" are a tool in learning the Solar System. This props is a unit of several components of props that can visualize various phenomena such as rotations and revolutions of the earth and moon, solar and lunar eclipses, tides of seawater, position of celestial bodies in their orbits, and artificial satellite motion. Named "Kiara Payung" because the components of the model of the solar system phenomenon are integrated to form a shade tree "Kiara Payung" which is planted in the school environment. While the word "Payung" to remind that the framework of used umbrellas as one of the materials for making props. The purpose of the use of teaching aids is to concretize the material of the solar system as well as to improve student learning outcomes. The effort to concretize the material is done by modeling the teaching aids in the classroom, while to find out the improvement in student learning outcomes is used the test method. The test is conducted twice at the end of each subject. Test data retrieval is focused on the VI C, which has always been lower than other class VI. Learning outcomes show that by using the props "Kiara Payung" students' understanding of the material of the solar system is better. In addition, there is an increase in student learning outcomes. As many as 34 students in grade VI C, in the first test learning completeness only reached 73,6% and in the next test it increased to 91,2%

Clarifying the Eclipse

Abstract This essay examines a literary exchange between the Visigothic poet-king Sisebut (612-621 AD) and his scholar-bishop Isidore of Seville following an anomalous sequence of eclipses. After Sisebut commissioned a scientific treatise from Isidore on such natural phenomena, he responded to the bishop’s prose with a short poem on lunar eclipses (De eclipsi lunae). This study interprets the exchange of texts not as a literary game, but as high-stakes political correspondence. It situates the king’s verses in an ongoing process of cultural construction in Visigothic Spain, led prominently by Isidore himself, but also tied to a rising ascetic movement. It argues that Sisebut was attuned to Isidore’s designs to manage the discourses through which Christian power was proclaimed, and shows how the king attempted to versify in accord with scientific truth so as to fit within Isidore’s ascetic intellectual program.

P6153High risk plaque by coronary CTA predict cardiac events but not all-cause mortality: long term follow up

Abstract Background Ultra long-term (10 years) outcome data of coronary computed tomography angiography (CTA) for coronary heart disease (CHD) screening are lacking. Novel CTA imaging biomarkers (“high-risk-plaque”) may improve risk stratification. Aims To define CT-imaging predictors for long–term outcomes. Methods 1430 low-to-intermediate-risk patients (mean age 57.9 years; 44.4% females) were included into our prospective cohort study. Coronary Calcium Score (CCS) and CTA were performed. CTA was evaluated for: Stenosis severity (minimal<25%; mild<50%; moderate 50–70%; severe >70%) (CADRADS 1–4), total mixed plaque burden (G-score), high–risk-plaque criteria: 1) low attenuation plaque 2) Napkin-ring (“lunar-eclipse” sign) 3) spotty calcification 4) remodeling index Primary endpoint was all-cause mortality, secondary endpoints cardiovascular mortality and composite (non-fatal and fatal) MACE. Results Over a follow-up of mean 10.55 years ±1.98 (range, 6.1–12.8), all-cause mortality rate was 106 (7.4%), cardiovascular mortality 25 (1.75%) and composite MACE 57 (4%). In patients with negative CTA, cardiovascular mortality was 0% and composite MACE rate 0.2%. Stenosis severity (CADRADS) was the strongest predictor for all 3 endpoints (p<0.001) on multivariate analysis (unadjusted and adjusted for risk factors, p<0.001) but calcium score >100 AU only predicted mortality on the unadjusted multivariate analysis (p=0.045) but not on the adjusted. On multivariate analysis, G-score (p<0.0001), LAP<60HU and the Napkin-Ring predicted composite MACE (p<0.001) but not all-cause mortality, before and after adjusting for risk factors (p=0.007 and 0.001 for LAP<60HU and Napkin-Ring, respectively) while spotty calcification and remodeling index did not. 465 had calcium score zero and in 156 (33.5%) of those, noncalcified fibroatheroma were found (total rate, 11%), 4.9% had >50% stenosis. However only 1 patient with calcium score zero died while there were 6 MACE. High risk plaque with “lunar eclipse” Conclusions Long-term prognosis is excellent if CTA is negative. Stenosis severity by CTA predicts all-cause and cardiovascular mortality, while calcium score predicts only mortality. Plaque burden and the high-risk plaque criteria LAP<60 and Napkin-Ring (syn. “lunar eclipse”) are strong predictors of MACE, but not all–cause mortality. Coronary CTA outperforms calcium scoring for risk stratification.

Using a Simple Method to Estimate (Approximate) the Angle Between the Lunar Orbit and the Ecliptic

This paper describes a method to demonstrate that the plane of the lunar orbit around Earth and the plane of the ecliptic (the plane of Earth’s orbit around the Sun) are inclined with respect to each other, and to present a method for measuring the angle of the inclination. The angle between the diameter of the Moon’s orbit when the Moon passes through the local meridian and the diameter of Earth’s orbit when the Sun passes through the local meridian is the angle between the two planes. The paths of the Sun and the Moon as they appear when the Sun is at the local meridian were defined and the angle between them was measured as 42.5° by an observer. Then, these measurements were used to determine the inclination and to calculate an approximate value for the angle between the plane of the lunar orbit and plane of the ecliptic, which was found to be approximately 4.5°. This angle could be closely approximated with a simple method that everyone could use realistically and provide an answer for the question, “Since there is a full Moon every month as well as a new Moon, why is there no lunar eclipse and solar eclipse every month?”

Ibn al-Fahhād and the Great Conjunction of 1166 AD

Farīd al-Dīn Abu al-Ḥasan ‘Alī b. al-Fahhād’s astronomical tradition as represented in the prolegomenon to his Alā’ī zīj (1172 AD) shows his experimental examination of the theories of his predecessors and testing the circumstances of the synodic phenomena as derived from the theories developed in the classical period of medieval Middle Eastern astronomy against his own observations. This work was highly influential in late Islamic astronomy and was translated into Greek in the 1290s. He evaluated al-Battānī’s Ṣābi’ zīj (d. 929 AD) and al-Khāzinī’s Sanjarī zīj (fl. 1115 AD) with regard to the conjunction between Jupiter and Saturn in 1166 AD and found the errors of, respectively, about 35 and 10 days in the times predicted, which are verified by a recalculation on the basis of these works and modern theories. His inspection of the four solar theories established by his Islamic predecessors with respect to the quantitative differences between their predicted times for the occurrence of the vernal equinoxes is also correct. His calculation of the parameters of the solar and lunar eclipses in April 1176 has the errors of up to 1 h in the time and one digit in the magnitude. A general result of this study is that solely the evaluation of the synodic phenomena could mislead the judgment about the reliability and worthiness of the contemporary theories.

On Dating the Lunar Eclipse of Alexander and the Battle of Gaugamela: Discussion of Evidence and Use of Archaeoastronomy for Chronology

Here we propose an archaeoastronomical discussion of evidence concerning the dating of the Battle of Gaugamela. This battle was preceded by a total lunar eclipse, which is also known as the eclipse of Alexander, used to date the decisive battle of the invasion of the Persian Achaemenid Empire. This eclipse is one of the many used for chronology.

Taklif of Lunar and Solar Eclipse Prayers According to Fiqh and Scientific Perspective

The motion of earth, moon and sun result in natural phenomena which people can directly see and tangibly experience. They occur globally yet are experienced locally, such as the phenomenon of solar and lunar eclipses. In Islamic studies discussion, this leads to specific consequence relating to taklif (compulsion) of worship to perform eclipse prayers. Therefore, this study aims to elaborate whether the local eclipse phenomenon could apply the taklif globally. Another question is on when the obligation is urged to Moslem.Using the approach of fiqh and science through descriptive-analytic method, this study finds that in scientific perspective, both solar and lunar eclipses are sunnatullah or natural phenomenon relating to rotation of earth, moon and sun. From the earth, this phenomenon comes in two types of condition. First, it could be both computed and witnessed, while second, it could only computed but not everyone could eye-nakedly witness it. In fact, solar eclipse, for instance, although globally accessible through digital instruments, could be only manually seen in any local and limited area. Therefore, in the fiqh based perspective, the taklif of eclipse prayers only applies based on matlak wilayatul hukm. It is based on the strong belief that hisab indicates the occurrence of eclipse on any certain area in Indonesia and is empirically proved. The taklif, therefore, only applies for those who see the phenomenon, (Pergerakan bumi, bulan dan matahari mengakibatkan terjadi fenomena alam yang dapat dilihat dan dirasakan secara nyata. Fenomena ini bersifat glabal, akan tetapi dirasakannya secara local seperti fenomena gerhana matahari dan bulan. Dalam kajian keislaman, fenomena ini memunculkan akibat khusus yang berkaitan dengan taklif ibadah, yakni salat gerhana matahari dan bulan. Apakah fenomena gerhana yang bersifat lokal tersebut dapat berlaku secara global, dan kapan taklif tersebut terbebankan pada setiap umat muslim? Dengan pendekatan fiqh dan sains secara deskripstif analitis, artikel ini menemukan bahwa dalan perspektif sains, fenomena gerhana matahari dan bulan adalah sunnatullah yang berkaitan dengan rotasi bumi, bulan dan matahari. Bagi penduduk bumi, fenomena ini dapat dialami dalam dua kondisi, yaitu pertama, dikomputasi sekaligus disaksikan, dan kedua dikomputasi, akan tetapi tidak semua semua orang bisa menyaksikan. Karena itu, fenomena gerhana matahari walaupun dapat dikomputasi secara global, akan tetapi hanya dapat disanksikan secara lokal. Dengan demikian, dalam prsepektrif fiqh, taklif ibadah salat gerhana diberlakukan berdasarkan matlak wilayatul hukm, yaitu apabila diyakinkan bahwa secara hisab menunjukkan terjadi gerhana dalam kawasan tertentu di Indonesia dan dapat dibuktikan dengan fenomena empiriknya, maka taklif salat gerhana tersebut hanya berlaku bagi mereka yang menyaksikan fenomena gerhana tersebut.)

Taklif of Lunar and Solar Eclipse Prayers According to Fiqh and Scientific Perspective

The motion of earth, moon and sun result in natural phenomena which people can directly see and tangibly experience. They occur globally yet are experienced locally, such as the phenomenon of solar and lunar eclipses. In Islamic studies discussion, this leads to specific consequence relating to taklif (compulsion) of worship to perform eclipse prayers. Therefore, this study aims to elaborate whether the local eclipse phenomenon could apply the taklif globally. Another question is on when the obligation is urged to Moslem.Using the approach of fiqh and science through descriptive-analytic method, this study finds that in scientific perspective, both solar and lunar eclipses are sunnatullah or natural phenomenon relating to rotation of earth, moon and sun. From the earth, this phenomenon comes in two types of condition. First, it could be both computed and witnessed, while second, it could only computed but not everyone could eye-nakedly witness it. In fact, solar eclipse, for instance, although globally accessible through digital instruments, could be only manually seen in any local and limited area. Therefore, in the fiqh based perspective, the taklif of eclipse prayers only applies based on matlak wilayatul hukm. It is based on the strong belief that hisab indicates the occurrence of eclipse on any certain area in Indonesia and is empirically proved. The taklif, therefore, only applies for those who see the phenomenon, (Pergerakan bumi, bulan dan matahari mengakibatkan terjadi fenomena alam yang dapat dilihat dan dirasakan secara nyata. Fenomena ini bersifat glabal, akan tetapi dirasakannya secara local seperti fenomena gerhana matahari dan bulan. Dalam kajian keislaman, fenomena ini memunculkan akibat khusus yang berkaitan dengan taklif ibadah, yakni salat gerhana matahari dan bulan. Apakah fenomena gerhana yang bersifat lokal tersebut dapat berlaku secara global, dan kapan taklif tersebut terbebankan pada setiap umat muslim? Dengan pendekatan fiqh dan sains secara deskripstif analitis, artikel ini menemukan bahwa dalan perspektif sains, fenomena gerhana matahari dan bulan adalah sunnatullah yang berkaitan dengan rotasi bumi, bulan dan matahari. Bagi penduduk bumi, fenomena ini dapat dialami dalam dua kondisi, yaitu pertama, dikomputasi sekaligus disaksikan, dan kedua dikomputasi, akan tetapi tidak semua semua orang bisa menyaksikan. Karena itu, fenomena gerhana matahari walaupun dapat dikomputasi secara global, akan tetapi hanya dapat disanksikan secara lokal. Dengan demikian, dalam prsepektrif fiqh, taklif ibadah salat gerhana diberlakukan berdasarkan matlak wilayatul hukm, yaitu apabila diyakinkan bahwa secara hisab menunjukkan terjadi gerhana dalam kawasan tertentu di Indonesia dan dapat dibuktikan dengan fenomena empiriknya, maka taklif salat gerhana tersebut hanya berlaku bagi mereka yang menyaksikan fenomena gerhana tersebut.)

On Dating the Lunar Eclipse of Alexander and the Battle of Gaugamela: Discussion of Evidence and Use of Archaeoastronomy for Chronology

On Dating the Lunar Eclipse of Alexander and the Battle of Gaugamela: Discussion of Evidence and Use of Archaeoastronomy for Chronology