Observational Astronomy

Gallium doped germanium detector arrays in a 16x25 pixel configuration will be used on two future instruments: In the spectrometer section of the Photodetector Array Camera and Spectrometer (PACS) aboard the Herschel satellite and the Field Imaging Far Infrared Line Spectrometer (FIFI LS) aboard the Stratospheric Observatory for Infrared Astronomy (SOFIA). Arrays of slightly stressed Ge:Ga detectors cover a wavelength range from 55 to 105 micron for PACS and from 40 to 120 micron for FIFI LS, whereas arrays of highly stressed Ge:Ga detectors cover a wavelength range from 105 to 210 micron for PACS and 120 to 210 micron for FIFI LS. The entire arrays consist of 25 independent modules of 16 pixels. The detector arrays will be operated with multiplexed integrating amplifiers with cryogenic readout electronics located close to the detector modules. The design of the detector arrays and results of first performance measurements will be reported.

This research is a new addition to the previous work carried out in Egypt to determine the altitude of the sun (sun vertical depression) corresponding to the beginning of the twilight. The observations of this issue began since more than 60 years in our institute and were attended by many astronomers and astrophysicists. Naked-eye (N.E) twilight observations of morning twilight were carried out in good viewing conditions by four instruments: two digital cameras, CCD cameras and SQM during the time interval (Aug. 2015-Dec. 2019) in many regions in Egypt by several research groups. The regions in Egypt were: Kottamia observatory, Kharga, Aswan, Hurghada, Marsa-Alam and Fayum. More than 30 scientific observers and amateurs participated in these observations. The purpose of these measurements was to determine the sun vertical depression of the sun below the horizon, D o (D o =-altitude of the sun) at which the normal eye can discriminate the true dawn (strong horizontal white thread). The results of these measurements indicated that the true dawn by the naked eye was observed at sun vertical depression D o = 14.56° (mean + 1SD)), while it was ranged from D o = 14° to 15° by measuring the light intensity using multi instruments depending on three different criteria for eye threshold of M, M1 and M2 (in the moonless sky conditions). The full hierarchical shape of the false dawn does not occur regularly in every morning. Generally, the interval time of the false dawn was found to be within 15° ≤ D o ≤ 18°. In the most morning twilight days, the percentage of color portion was Blue > Green > Red before D o ≈ 13.5° and it changes its behavior after this degree.

HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

The anomalous increase of the astronomical unit, the mysterious secular increase of the lunar eccentricity and the flyby anomaly are important issues of modern astronomy. This study aims to determine the effect of earthquakes on the origin of these anomalies. Based on conventional physics, we found the existence of earthquake-induced gravitational weakening within the earth-moon-sun system and beyond. New equations of gravitation, including time dilation, are introduced that can explain the anomalous increase of the astronomical unit and the lunar orbit. A modified equation that includes the effect of massive quakes also explains the anomalous increase of the lunar eccentricity. Furthermore, the results of the present study can explain the flyby and Pioneer anomalies experienced by spacecraft during gravity assisted maneuvers. A modification of the 3 rd Law of Kepler is also presented. Implications on the elliptic orbit of the earth, its reduced velocity and the occurrence of leap years are also discussed. Using the seismic-induced gravitational weakening model, probable trigger mechanisms of the faint young sun paradox and the Allais effect are also presented. An estimate of the age of the earth based on the observed values of the Hubble parameter and the USGS earthquake data for the past century is also presented. A new model of the seismic-driven expanding universe and a new equation to determine the expansion rate of galaxies and the universe is also proposed. The sudden earth's retreat due to gravitational weakening and its implication on anomalous astronomical refraction and flight risk at night especially near the equatorial region, and its effect on the abrupt satellite orbital decay, spin and drift are also discussed. This study may also shed light on the occurrence of sinkholes and massive landslides. Finally, this study proposes a new equation that can explain the observed changes in the fine structure constant.

After a brief review of the Decreasing Universe (D.U.) model, we will derive a formula and the graph for the apparent velocity of stars (of a Messier_33 galaxy) as a function of their radial distance from the galactic center. This formula reproduces the same velocity curve traditionally attributed to dark matter.

We have a packed issue this month as we near the end of the CSIRO 75th Anniversary year. As a tribute to this milestone we look at our past (see the historical articles by Wayne Orchiston and John Archer), our present (read about progress in the current ATCA MNRF upgrade), as well as to the future (great news on the success of the new MNRF proposal for Australian astronomy). We hope you will enjoy reading all the latest ATNF news here or on the web at . The next issue the ATNF News will be distributed in February 2002. As always, contributions are welcome. Enjoy the Christmas and New Year holidays and see you in 2002.

يلقي هذا البحث الضوء على المعبود ساح الذي يعد الكوكبة الرئيسية بالسماء الجنوبية وذلك من خلال طرق كتابة إسمه المختلفة بالنصوص المصرية القديمة الدينية مثل نصوص الأهرام، متون التوابيت، كتاب الموتى، الإمدوات بالإضافة للطرق كتابته بالمواقع الأثرية والأثار المختلفة مثل المقابر، المعابد والتوابيت.  تناول البحث كذلك بالدراسة الهيئات المختلفة التي ظهر من خلالها ساح سواء هيئة النجم أو الهيئة الآدمية والفروق الموجودة بالهيئات الآدمية التي ظهر خلالها سواء من خلال التيجان أو الصولجانات والرموز التي يحملها أو وضعية الجسد.  تم كذلك دراسة أبرز الأدوار التي لعبها ساح بالديانة المصرية القديمة وتبين من خلال الدراسة أنه كان يظهر بشكل موسمي وليس دائم بالسماء حيث أعتقد أنه يظهر من العالم السفلي وارتبط بالعديد من الأرباب والربات فكان إبناً لرع ونوت، كما وصف بأنه روح أوزير فارتبط به كما ارتبط بالربة سوبدت فجسدا معا السماء الجنوبية وكان أحد الآلهة العظيمة الذين يمثلون نجوم إيزيس، وارتبط بالمتوفى وأعتبر أن نوت تلدهما معاً كما أعتبر المتوفى رفيق لساح يعبر معه للسماء.

Christina Kirch (1697-1782) and Margaretha Kirch (b. 1703), daughters of astronomer Gottfried Kirch (1639-1710) and Maria Margaretha née Winckelmann (1670-1720), sisters of astronomer Christfried Kirch (1694-1740), continued a family tradition of practicing astronomy, conducting meteorological observations, and making calendars. The article presents the history of the Kirch sisters, from their initial steps in astronomical practice during their parents' lifetime to being fi nancially supported by the Royal Prussian Society of Sciences after their brother's death, and Christina's subsequent role in making calendars for Silesia. The analysis of the stages of the Kirch's daughters' introduction to celestial observations is supplemented by examples of the participation of their half-sister Theodora (b. 1683) in auxiliary astronomical works.

HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Ce dossier scientifique se resume dans un premier temps, a tenter l’aventure d’une histoire totale sur quelques 160 annees de developpement d’une navigation astronomique et chronometrique de haut niveau, de 1749 a 1905 environ, envisagee sous les angles les plus varies et complementaires, avec l’ambition de reecrire quelques grandes pages de l’histoire de l’astronomie et de l’histoire de la navigation, au cours des XVIIIe et XIXe siecles. Ainsi, il y est question du developpement et de la diffusion des methodes de navigation astronomiques et chronometriques par les astronomes et les marins eux-memes ; des developpements de la mecanique celeste lunaire (theories et tables des mouvements de la Lune) pour la diffusion de la methode si delicate des distances lunaires et les besoins de la navigation ; de la conception et de la diffusion des tables astronomiques et nautiques jusqu’au debut du XXe siecle (histoire des ephemerides de la Connaissance des temps) qui conduisent a s'interes...

This is a thesis for the probability of past, advanced cultures, and civilizations on every continent that were linked by communication and an uncanny system of similar/common beliefs.  What were people thinking?  I will look at the ancient Egyptian, Sumerian, Maya, Israeli, and Celtic cultures.  The focus will be on Giza, Newgrange, Angkor Wat, Thebes, and Stonehenge.

We report the discovery of the closest collisional ring galaxy to the Milky Way. Such rare systems occur due to 'bulls-eye' encounters between two reasonably matched galaxies. The recessional velocity of about 840 km s -1 is low enough that it was detected in the Anglo-Australian Observatory/UK Schmidt Telescope Survey for Galactic H α emission. The distance is only ∼10 Mpc and the main galaxy shows a full ring of star-forming knots, 6.1 kpc in diameter surrounding a quiescent disc. The smaller assumed 'bullet' galaxy also shows vigorous star formation. The spectacular nature of the object had been overlooked because of its location in the Galactic plane and proximity to a bright star and even though it is the 60th brightest galaxy in the HI Parkes All Sky Survey (HIPASS) H I survey. The overall system has a physical size of ∼15 kpc, a total mass of M * = 6.6 × 10 9 M (stars + H I), a metallicity of [O/H]∼ -0.4, and a star formation rate of 0.2-0.5 M yr -1 , making it a Magellanictype system. Collisional ring galaxies therefore extend to much lower galaxy masses than commonly assumed. We derive a space density for such systems of 7 × 10 -5 Mpc -3 , an order of magnitude higher than previously estimated. This space density suggests Kathryn's Wheel is the nearest such system. We present discovery images, CTIO 4-m telescope narrow-band follow-up images and spectroscopy for selected emission components. Given its proximity and modest extinction along the line of sight, this spectacular system provides an ideal target for future high spatial resolution studies of such systems and for direct detection of its stellar populations.

We have conducted a multi-wavelength study of the planetary nebula Abell 48 and give a revised classification of its nucleus as a hydrogen-deficient star of type [WN4]. The surrounding nebula has a morphology typical of PNe and importantly, is not enriched in nitrogen, and thus not the 'peeled atmosphere' of a massive star. Indeed, no WN4 star is known to be surrounded by such a compact nebula. The ionized mass of the nebula is also a powerful discriminant between the low-mass PN and high-mass WR ejecta interpretations. The ionized mass would be impossibly high if a distance corresponding to a Pop I star was adopted, but at a distance of 2 kpc, the mass is quite typical of moderately evolved PNe. At this distance, the ionizing star then has a luminosity of ∼5000 L ⊙ , again rather typical for a PN central star. We give a brief discussion of the implications of this discovery for the late-stage evolution of intermediate-mass stars.

This paper presents (Hα + [Nii]) imaging and spectroscopy of a previously unknown, highly evolved planetary nebula of low excitation which is in the first stages of an interaction with the interstellar medium (ISM). It was discovered serendipitously from AAO/UKST Hα Survey images as part of a project to exploit the survey data and has evaded detection by previous surveys due to its very low surface brightness. It is a remarkable hollow-sphere planetary nebula, some 19´ across, making it one of the largest examples of its type. We estimate a radius of 1.5 pc and a distance of 550 pc as derived from a new Hα surface brightness–radius relation. PFP 1 has near-perfect circular symmetry, broken only at the north-western edge which is coupled with significantly increased (Hα + [Nii]) intensity, both of which provide evidence for an interaction with the ISM. We find a near solar composition for this object with possibly enhanced He and N abundances. A blue central star candidate has been i...

The total number of true, likely and possible planetary nebulae (PN) now known in the Milky Way is nearly 3000, double the number known a decade ago. The new discoveries are a legacy of the recent availability of wide field, narrowband imaging surveys, primarily in the light of H-alpha. In this paper, we summarise the various PN discovery techniques, and give an overview of the many types of objects which mimic PN and which appear as contaminants in both Galactic and extragalactic samples. Much improved discrimination of classical PN from their mimics is now possible based on the wide variety of high-quality multiwavelength data sets that are now available. We offer improved taxonomic and observational definitions for the PN phenomenon based on evaluation of these better diagnostic capabilities. However, we note that evidence is increasing that the PN phenomenon is heterogeneous, and PN are likely to be formed from multiple evolutionary scenarios. In particular, the relationships be...

We present a detailed study of a bipolar, possible Type I planetary nebula (PN), PHR 1315-6555 (PN G305.3-03.1), which was discovered as part of the Macquarie/AAO/Strasbourg Hα planetary nebula project (MASH), and that we considered at the time was an excellent candidate for membership of the distant, compact, intermediate-age open cluster, ESO 96-SC04. The strong evidence for this association is presented here, making this the only known example of a PN physically associated with a Galactic open cluster. Cluster membership is extremely important as it allows for very precise estimates of the fundamental properties of the PN as the cluster is at a known distance. The PN was discovered by one of us (QAP) during systematic MASH searches for new Galactic PNe of the AAO United Kingdom Schmidt Telescope (UKST) Hα survey and had been missed in earlier broad-band surveys, including specific CCD studies of the host cluster. We present original discovery images and Cerro Tololo Inter-American Observatory (CTIO) 4-m MOSAIC-II camera follow-up narrowband images that reveal its bipolar morphology. We also present (i) low-resolution optical spectra that spectroscopically confirm the PN, (ii) accurate radial velocities of PN and cluster stars from high-resolution spectroscopy which show they are consistent and (iii) a reliable, independent distance estimate to the PN using a robust PN distance indicator which agrees with the published cluster distance to within the errors. We also provide preliminary estimates of basic PN properties and abundance estimates from deeper spectra that show it to be of possible Type I chemistry. This is also consistent with its estimated turn-off mass. Taken together, these findings present a powerful case for clear physical association between the PN and host cluster. Results for this association will be of considerable interest to specialists across differing astrophysical disciplines, including PNe, white dwarfs and open clusters.

We present AAO/UKST Hα+[N II] narrow-band imagery and low-and medium-resolution optical spectroscopy of RCW 24 and RCW 69. These nebulae were previously classified as H II regions, but we now show them to be two of the largest and nearest bipolar Type I PNe yet discovered. Distances were estimated using extinction-distance and kinematic methods, and via a new Hα surface brightness-radius relation. The adopted distances are 1.0 ± 0.3 kpc for RCW 24 and 1.3 ± 0.2 kpc for RCW 69. Both objects have enhanced nitrogen abundances, with log N/O +0.44 for RCW 24, and log N/O = +0.33 for RCW 69. Systemic velocities and |z| distances are V LSR = +5 km s -1 and |z| ∼ 23 pc for RCW 24, and V LSR = -33 km s -1 and only |z| ∼ 7 pc for RCW 69. Both PNe originated from massive progenitors (>2.0-2.5 M ), as deduced from their chemical abundances, large ionized masses, small |z| distances, low peculiar velocities and relatively hot central stars. These two objects form an important addition to the small sample of evolved bipolar PNe in the solar neighbourhood.

Монографія присвячена життю і творчості видатного американського астрофізика, уродженця України, Отто Людвіговича Струве. Розповідь автора охоплює всі сфери наукового генія останнього представника знаменитої астрономічної династії Струве - новатора зоряної спектроскопії, який стояв біля витоків радіоастрономії, заслуженого лауреата всіх престижних премій в галузі астрономії, віце-президента, а потім президента Міжнародного астрономічного союзу. Всі періоди його бурхливого життя в цій книзі доповнені документальним матеріалом: фрагментами з листування вченого, спогадами про нього, які не були опубліковані. Подано повну бібліографію праць вченого (понад 1000 робіт). / The monograph is dedicated to the life and work of an outstanding American astrophysicist, native of Ukraine, Otto Struve. The author’s narrative covers all areas of the scientific genius of the last representative of the famous astronomical dynasty Struve - an innovator in stellar spectroscopy, who stood at the origins of radio astronomy, honored winner of all prestigious awards in the field of astronomy, vice president, and then president of the International Astronomical Union. All periods of his turbulent life in this book are supplemented by documentary material: fragments from the scientist’s correspondence, memoirs about him that were not published. A complete bibliography of the scientist’s works is given (more than 1000 works).

A set of computational routines has been employed for calculating in real time the trajectories of N charged bodies which are acted upon by electromagnetic forces of the CoulombAbraham-Lorentz type. These routines yield the complete solution of the motion equation for the “classical atom”. The computer code that evaluates the interaction effect is interesting in itself because it contains the radiation damping term, which is proportional to the timederivative of the acceleration; this is often a cumbersome analytical and interpretational task. The results permit the graphical representation of the trajectories and, a reasonable estimate of the “collapse time”. Subject headings: radiation by moving charges — computational techniques and simulations — classical electrodynamics

ABSTRACT
Millisecond pulsars (MSPs) in binary systems are precise laboratories for tests of gravity and the physics of dense matter. Their orbits can show relativistic effects that provide a measurement of the neutron star mass and the pulsars are included in timing array experiments that search for gravitational waves. Neutron star mass measurements are key to eventually solving the neutron star equation of state and these can be obtained by a measure of the Shapiro delay if the orbit is viewed near edge-on. Here, we report on the timing and noise analysis of five MSPs observed with the MeerKAT radio telescope: PSRs J0900–3144, J0921–5202, J1216–6410, J1327–0755, and J1543–5149. We searched for the Shapiro delay in all of the pulsars and obtain weak detections for PSRs J0900–3144, J1216–6410, and J1327–0755. We report a higher significance detection of the Shapiro delay for PSR J1543–5149, giving a precise pulsar mass of
M
and companion white-dwarf mass
 M
⁠. This is an atypically low-mass measurement for a recycled MSP. In addition to these Shapiro delays, we also obtain timing model parameters including proper motions and parallax constraints for most of the pulsars.

Розглянуто діяльність представників Харківської астрономічної обсерваторії щодо створення упродовж 1930-х років нового сучасного астрономічного центру загальнореспубліканського значення. Метою роботи є узагальнення результатів комплексного історико-наукового дослідження створення центральної Української обсерваторії у Харкові на базі обсерваторії Харківського державного університету імені О. М. Горького у визначений період. Застосовано спеціальні методи, використання яких дозволило з’ясувати техніко-економічні та соціальні передумови винесення інструментальної бази Харківської астрономічної обсерваторії за межі міста; визначити географічні локації та основні етапи розвитку подій з обстеження потенційних районів для облаштування нової обсерваторії; дослідити особливості процесу організації і проведення астрономо-метеорологічних спостережень; конкретизувати персональний внесок представників університетської обсерваторії у процесі створення закладу, зокрема, М. М. Євдокимова, М. П. Барабашова, Б. П. Герасимовича, Б. Є. Сємейкіна, П. Г. Пархоменко та ін. Розглянуто мету та принципи створення центральної астрономічної обсерваторії у Харкові; з’ясовано проблематику перспективних наукових досліджень та рівень інструментальної бази нової обсерваторії, які передбачалося реалізувати у цьому проєкті, доведено актуальність запропонованих архітектурно-будівельних рішень для цього комплексу обсерваторських споруд; висвітлено факти, за яких проєкт залишився нереалізованим. Проведене дослідження продовжує проблематику робіт, присвячених історії розвитку вітчизняної астрономічної науки, та є одним з етапів на шляху до вивчення історії астрономії у Харкові періоду 1930-х років. / The activity of the Kharkiv Astronomical Observatory members on the establishment of a new modern astronomical center of national significance during the 1930s is сonsidered. The aim of this work is to summarize the results of a comprehensive historical and scientific study of the founding of the Central Ukrainian observatory in Kharkiv on the basis of the University Observatory of Gorky Kharkiv State University  in a certain period. Special methods were used, that allowed to clarify the technical, economic and social preconditions for bringing outside the city the instrumental base of the Kharkiv Astronomical Observatory; to identify geographical locations and the main steps of examination of potential areas for the construction of a new observatory; to study the circumstances of the process of organizing and conducting astronomical and meteorological observations; to specify the personal contribution of the representatives of the university observatory in the process of creating the institution, in particular, Mykola Evdokimov, Mykola Barabashov, Boris Gerasimovich, Boris Semeykin, Praskovia Parkhomenko and others. The purpose and principles of establishment of the central astronomical observatory in Kharkiv are considered; the problems of perspective scientific researches and the level of instrumental base of the new observatory which were supposed to be realized in this project are clarified. The relevance of the proposed architectural and construction solutions for this complex of observatory buildings were proved; the reasons for the project remained unrealized were highlight. The study continues the work on the history of the development of domestic astronomical science and is one of the steps towards the study of the history of astronomy in Kharkiv in the 1930s.

У статті розглянуто науково-дослідну діяльність астрономічної обсерваторії Харківського університету під час Української революції 1917–1921 рр. Проаналізовано публікації харківських астрономів зазначеного періоду, присвячені фотометричним спостереженням зір, поглинанню світла та його відбиття від матових поверхонь, вивченню близькополюсних зір та зір типу бети Цефея, дослідженню Нової Орла 1918 та спостереженням планет. Автором застосовано спеціальні методи, використання яких дозволило виділити основні
етапи розвитку астрономії у досліджуваному періоді, розкрити змістовність наукового потенціалу харківських астрономів. З’ясовано біографічні відомості представників харківської астрономії та висвітлено їх участь у подіях громадянської війни. Висвітлено питання трансформації Харківської астрономічної обсерваторії на тлі перетворень Харківського університету у 1920–1921 рр. Передбачається, що матеріали історико-наукового дослідження будуть використані в науково-дослідній роботі з історії астрономії у Харкові першої половини ХХ ст. / The article deals with the research activities of the Astronomical Observatory of Kharkiv University during the Ukrainian Revolution of 1917-1921. The publications of Kharkiv astronomers of this period are analyzed, which are devoted to photometric observations of stars, light absorption and reflection from matte surfaces, the study of near-polar stars and stars of the beta Cepheus type, the study of the Nova Aquilae 1918, and planetary observations. The author has applied special methods, the use of which allowed to highlight the main stages of the development of astronomy in the studied period, to reveal the content of the scientific potential of Kharkiv astronomers. The biographical information of the representatives of Kharkiv astronomy is revealed and their participation in the events of the Civil War is highlighted. The transformation of the Kharkiv Astronomical Observatory against the background of the transformations of Kharkiv University in 1920-1921 is highlighted.

Существуют исследования, описывающие влияние высокоскоростного удара объекта о поверхность металла. Однако эти исследования основаны на экспериментах, проведенных с «чистыми» неметаллическими материалами, такими как оксиды, карбиды и т.д. В реальных условиях неметаллические объекты имеют сложный состав и неоднородную структуру, в частности, они могут быть представлены минералами. Целью настоящей работы является выявление особенностей разрушения металлической преграды и неметаллического пробойника при высокоскоростном взаимодействии для использования результатов в оптимизации конструктивных решений защиты изделий специального назначения. В качестве объекта исследования рассматриваются титановая металлическая преграда и пробойник из горной породы габброидного типа (силикатного типа) сферической формы. Скорость образца пробойника составляла 340 м/с, скорость съемки 25 000 кадр/с, время экспозиции 1/71 000 с. Разрешение полученных снимков изображений составило 512 × 400 пикселей. Удар пробойником осуществляли под углом 90° к поверхности в середину и с краев металлической преграды. Установлено, что в момент удара пробойником в месте соударения возникает интенсивное взаимодействие, сопровождающееся выделением температуры, о чем свидетельствует зафиксированный при съемке сноп искр, после удара по всей протяженности металлической преграды распространяются упругие колебания, неметаллический пробойник фрагментируется. Также неметаллический пробойник при столкновении с металлической преградой испытывает воздействие отраженной ударной волны в виде кинетической энергии преграды и диссипирует (рассеивает) ее. Полученные сведения об особенностях разрушения металлической преграды и неметаллического пробойника при высокоскоростном взаимодействии позволят найти оптимальные конструкционные решения защиты специальных изделий при их эксплуатации. Ключевые слова: каменное литье, синтетический минеральный сплав, фрагментация, хрупкое разрушение, деформация, удар, трещины, механика разрушения, диссипация, видеофиксация.

anthropozoologica Brice EPHREM & Enora LE QUÉRÉ À propos de la pratique présumée de la pêche aux cétacés dans l'Antiquité. Nouvelles interprétations du chant V des Halieutiques d'Oppien de Cilicie grâce au croisement des sources art. 60 (2)-Publié le 7 février 2025 www.anthropozoologica.com 2025 • 60 • 2 Inist Anthropozoologica est indexé dans / Anthropozoologica

In this special issue, we aim to study the places where observations, experiments, studies and instruments were practised, in France, between the fifteenth century and the end of the eighteenth century. We want here to react to previous existing studies on scientific observation, by focusing on the new and fundamental aspect of places and material conditions of observation and, complementary to the literature, by using especially images. While the prevailing literature has described places of observational practice (called observatories, laboratories, ateliers …) isolating them from their political, social and cultural context, these places were not created as a defined and complete category but they were imagined by the actors, cared for over time and adapted to all kinds of material needs.

The Journal of Computational Astronomy & Astronomical Computing is an effort by the FAAE-Grupo de Cálculo Astronómico (GCA) to encourage the use of software tools and the development of codes and algorithms for astronomical applications within the framework of amateur astronomy, as well as to connect the amateur community with the professional astronomy community and promote cross-collaboration and ProAm projects between both groups.

The rapid expansion of the use of maps across everyday life as well as the sciences and arts is changing our relationship to cartography. This article argues that we are experiencing a 'mapping revolution'. As the importance of mapping becomes clear, so to does the importance of considering both the diverse traditions of mapping and the potential of mapping in the field of astrogeography.

To our knowledge, representations of zodiac symbols are unattested in Egyptian rock art. The investigation of a petroglyph at the site of el-Hosh in Upper Egypt has found that it bears a strong resemblance to the zodiac sign of Capricornus, a composite figure combining the head and forequarters of a goat with the body of a fish. The sign first arose in Mesopotamia in the late third millennium BCE, from which it subsequently spread to the Mediterranean region. Following a review of the symbol's development in Egypt, in which its occurrence on ceilings, coffins, and coins was examined, we are confident that the petroglyph depicts Capricornus and that it was most likely produced during the Graeco-Roman Period. Furthermore, as the figure is related stylistically to a nearby petroglyph of a chameleon, an equally unique subject for Egyptian rock art, the latter can now be dated more firmly to the same era.

Context. The X-ray Integral Field Unit (X-IFU) that will be on board the Athena telescope will provide an unprecedented view of the intracluster medium (ICM) kinematics through the observation of gas velocity, ν, and velocity dispersion, w, via centroid-shift and broadening of emission lines, respectively. Aims. The improvement of data quality and quantity requires an assessment of the systematics associated with this new data analysis, namely biases, statistical and systematic errors, and possible correlations between the different measured quantities. Methods. We have developed an end-to-end X-IFU simulator that mimics a full X-ray spectral fitting analysis on a set of mock event lists, obtained using SIXTE. We have applied it to three hydrodynamical simulations of a Coma-like cluster that include the injection of turbulence. This allowed us to assess the ability of X-IFU to map five physical quantities in the cluster core: emission measure, temperature, metal abundance, velocity,...

Aims. We present the reconstruction of hydrostatic mass profiles in 13 X-ray luminous galaxy clusters that have been mapped in their X-ray and Sunyaev–Zeldovich (SZ) signals out to R200 for the XMM-Newton Cluster Outskirts Project (X-COP). Methods. Using profiles of the gas temperature, density, and pressure that have been spatially resolved out to median values of 0.9R500, 1.8R500, and 2.3R500, respectively, we are able to recover the hydrostatic gravitating mass profile with several methods and using different mass models. Results. The hydrostatic masses are recovered with a relative (statistical) median error of 3% at R500 and 6% at R200. By using several different methods to solve the equation of the hydrostatic equilibrium, we evaluate some of the systematic uncertainties to be of the order of 5% at both R500 and R200. A Navarro-Frenk-White profile provides the best-fit in 9 cases out of 13; the remaining 4 cases do not show a statistically significant tension with it. The dist...

Using the "Decreasing Universe" model [01] we will show evidence that this new model of the dynamics of the Universe is less disruptive and more adequate than the traditional Λ-CDM model that postulates the existence of Dark Energy. We will also develop, from this new theory, a simple and straightforward mathematical formula that provides the distance of the galaxy as a function of its redshift.

Deep observations of the Universe, usually as a part of sky surveys, are one of the symbols of the modern astronomy because they can allow big collaborations, exploiting multiple facilities and shared knowledge. The new generation of extremely large telescopes will play a key role because of their angular resolution and their capability in collecting the light of faint sources. Our simulations combine technical, tomographic and observational information, and benefit of the Global-Multi Conjugate Adaptive Optics (GMCAO) approach, a well demonstrated method that exploits only natural guide stars to correct the scientific field of view from the atmospheric turbulence. By simulating K-band observations of 6000 high redshift galaxies in the Chandra Deep Field South area, we have shown how an ELT can carry out photometric surveys successfully, recovering morphological and structural parameters. We present here a wide statistics of the expected performance of a GMCAO-equipped ELT in 22 well-known surveys in terms of SR.

Measuring Galaxy Properties in the Cluster Abell 160 CRAIG KOONTZ, JASON PINKNEY, Ohio Northern University -We develop a procedure for building a large catalog of cluster galaxies and their photometric properties, as measured with CCDs. Our first case, Abell 160, is relatively nearby and we have already obtained spectroscopic redshifts for its brightest galaxies. We have mosaiced this cluster in R and V filters using a CCD imager on the 1.3-meter McGraw-Hill telescope. We fit a world coordinate system to the images using the software "WCStools." We use "SExtractor" to extract sources from the images. We create software for merging catalogs in such a way as to avoid double counting, to reject cosmic rays, and to combine redundant measurements. The measured properties include magnitude, ellipticity, position angle, size, and color (V-R). We investigate the efficacy of our separation of galaxies and stars and find that it begins breaking down around R=19.0. We attempt to separate cluster members from foreground and background galaxies using the color-magnitude relation. In future work, we will investigate substructure (clumping) within clusters and its correlation with galaxy properties (especially color, size and morphology).

This thesis deals with the deposition, characterisation and optical study of thin films coatings designed for Extreme Ultraviolet (EUV) and soft x-ray optics. Single and multilayer thin films are important both for scientific and industrial purposes, developing knowledge of optical properties of materials in the EUV and soft x-rays plays a major role in determining performances of optical elements used in this spectral range. The optical constants of titanium dioxide (TiO2) have been experimentally determined at energies in the extreme ultraviolet and soft x-ray spectral regions, from 25.5 to 612 eV (2 to 48.6 nm), measuring angle-dependent reflectance of amorphous TiO2 thin films with synchrotron radiation at the BEAR beamline of Synchrotron ELETTRA. The experimental reflectivity profiles were fitted to the Fresnel equations using a genetic algorithm applied to a least-square curve fitting method, obtaining values for delta and beta. We compared our measurements with tabulated data...

The ‘Menhir of the Arabs’ or ‘La pierre percée = the Pierced Stone’ near the village of Draché has been known for a long time. However, to date there has been no detailed study of this outstanding megalithic monument. Despite the continuous need for a comprehensive geological/mineralogical evaluation, an up-to-date laser-scan-based documentation of work-traces, or even an excavation of its immediate surroundings, the almost ‘verticalised’ 4 m long-stone provides information that may render an understanding of its function less mysterious. In the following, reference is made to a few simple facts that suggest its use as a precursor of astronomical tubes and astronomical clocks (nocturlabia), as well as a resulting function as a seasonal sundial (meridienne). The recognition of the fundamental significance of the only supposed fixed point at the northern firmament for orientation/navigation and other more philosophical variants of orientation indeed represents a paradigm shift for prehistoric archaeology. The fact that the vast majority of prehistoric circumpolar representations known to date come from funeral contexts makes it clear that the horizons of thought in present-day prehistoric studies are at an early stage. "Tolerance is good, but not when it comes to intolerance" (Wilhelm Busch, 1832 - 1908).

Liminality and creative potentiality in the trickster, the taboo violator and a world-generating demiurge. Coincidence of unsettled tensions in the mythologies of Ariadne and the Minotaur, characters of rupture and transit. Cruel power transfer rituals. Primeval harmony loss and resulting depowering and demonization of feminine forces.
These are the themes that unfold from the macro polysemous center of the labyrinth.
Shifting from the mesmerizing power of the maze that towers in Saltburn, I have tried here to recompose them, albeit concealed beneath aesthetic redundancy and frivolous ostentation.