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2. INDIAN INITIATIVES TO ESTABLISH 'WESTERN' ASTRONOMICAL OBSERVATORIES PRIOR TO INDEPENDENCE. 2: COLLEGES AND UNIVERSITIES.
- Author
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Orchiston, Wayne and Kapoor, R. C.
- Subjects
ASTRONOMICAL observatories ,UNIVERSITIES & colleges ,METEOROLOGICAL services ,INDIANS (Asians) ,LOCAL government - Abstract
This paper outlines the efforts to establish Western-style astronomical observatories in India made by colleges and universities over the last century prior to Indian independence in 1947. The focus is therefore on the nineteenth-century emergence of the Presidency College Observatory in Calcutta, St. Xavier's College Observatory in Calcutta, Takhtasinghji Observatory in Poona, and Langat Singh College Observatory in Muzaffarpur. Three of these observatories were established either to aid educated Indians in gaining a realistic knowledge of Western astronomy, or so that India itself could contribute to that body of research knowledge. The fourth observatory, at the Presidency College in Calcutta, was a local government initiative founded primarily to provide a local time service and meteorological data. Unlike the observatories discussed in the first paper in this series, none of the observatories reviewed in this paper was set up primarily to further Britain's colonial ambitions. All were local Indian initiatives, but the critical involvement of Western astronomers or academics at three of the four observatories reveals that a colonial link was still there, albeit as an underlying element. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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3. THE BULLETIN OF THE VILNIUS ASTRONOMICAL OBSERVATORY: A COMPREHENSIVE OVERVIEW (1960-1992).
- Author
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Poškienė, Agnė, Vázquez, Carlos Viscasillas, and Mikolaitis, Šarūnas
- Subjects
ASTRONOMICAL observatories ,WORLD War II ,REINCARNATION ,ASTRONOMERS ,SCIENTIFIC community ,HISTORY of astronomy ,HISTORY of libraries - Abstract
During the eighteenth century professional astronomy started in Lithuania, and over time the first extensive astronomical publications appeared. The tradition of publishing a periodical astronomical Bulletin started in 1921, when Vilnius Astronomical Observatory was led by Polish astronomer Professor Władysław Dziewulski. The outbreak of the Second World War stopped the publication of Bulletins, and 1960 was a crucial year in the rebirth of astronomy in Lithuania. The revitalization of the Bulletin was very important for the Observatory's research and the expansion of the library. During the Soviet occupation, Lithuanian astronomers had limited links abroad. Thus, the Bulletin served as a way to disseminate astronomical research and establish links with international research institutions. This paper examines the history, personalities, contributions and importance to the scientific community of the Bulletin of the Vilnius Astronomical Observatory. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
4. An Improved Range-Searching Initial Orbit-Determination Method and Correlation of Optical Observations for Space Debris.
- Author
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Lei, Xiangxu, Xia, Shengfu, Liu, Hongkang, Wang, Xiaozhen, Li, Zhenwei, Han, Baomin, Sang, Jizhang, Zhao, You, and Luo, Hao
- Subjects
ORBIT determination ,SPACE debris ,ASTRONOMICAL observatories ,ORBITS (Astronomy) ,OPTICAL telescopes ,TELESCOPES - Abstract
The Changchun Observatory of the National Astronomical Observatories, Chinese Academy of Sciences, and the Shanghai Astronomical Observatory are used to generate very short arc (VSA) angle observations of objects in low Earth orbit (LEO) and geostationary orbit (GEO) with their ground-based electrical–optical telescope arrays (EA), the Changchun EA and SAO FocusGEO, respectively. These observations are used in this paper. The range-searching (RS) algorithm for initial orbit determination (IOD) is improved through the multiple combinations of observations and the dynamic range-searching step length. Two different computation modes (the normal mode and the refining mode) of the IOD computation process are proposed. The geometrical method for the association is used. The IOD and association methods are extended to the real optical observations for both LEO and GEO objects. The results show that the IOD success rate of arcs from the LEO objects is about 91%, the error of the semimajor axis (SMA) of the initial orbital elements is less than 50 km, and the correlation accuracy rate is about 89%. The IOD success rate of arcs from the GEO objects is higher than 88%, and the correlation accuracy rate is greater than 87%. The recent COSMOS 1408 antisatellite test (ASAT) generated a large amount of debris. The algorithm of this paper and the observations of Changchun EA are used to initially identify new debris, possibly from the ASAT through initial orbit determination and track association. Finally, 64 suspected new pieces of debris can be found. The results show the effectiveness of the IOD and the correlation algorithm, as well as the potential application of the optical–electrical array in studying space events. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
5. Revealing observatory networks through object stories: Introduction.
- Author
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Higgitt, Rebekah
- Subjects
OBSERVATORIES ,MATERIAL culture ,NETWORK analysis (Planning) ,SCIENTIFIC apparatus & instruments ,ASTRONOMICAL observatories - Abstract
This paper introduces a group of three articles that bring together object stories relating to observatory history and networks. The three articles ('Instrumental networks', 'Object itineraries' and 'Observatory audiences') each bring together three object stories by different authors that contribute to the article theme. Here the genesis of the collection at the workshops of the Observatory Sites and Networks project is discussed, along with the approaches taken and the kind of insights that studies of material culture can shed on histories of observatories and the observatory sciences. The arrangement of the stories into three themes is outlined while common threads and recurring motifs that create connections and synergies across the thematic sections are highlighted. Together the collected papers make an argument for the use of objects in research, demonstrating the fruitfulness of investigating their histories and showing how they can expand our understanding of the networks of people, organisations and objects that were interested in or essential to the successful functioning of observatories. They also demonstrate the breadth and variety of interests and resources that were drawn into these networks, offering new ways of understanding and interpreting both observatory sites and museum objects. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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6. Experience deploying an analysis facility for the Rubin Observatory's Legacy Survey of Space and Time (LSST) data.
- Author
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Mainetti, Gabriele, Hernandez, Fabio, Jammes, Fabrice, and Le Boulc'h, Quentin
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ASTRONOMICAL surveys ,ASTRONOMICAL observatories ,HIGH resolution imaging ,ASTRONOMICAL catalogs ,SURVEYS - Abstract
The Vera C. Rubin Observatory is preparing for the execution of the most ambitious astronomical survey ever attempted, the Legacy Survey of Space and Time (LSST). Currently in its final phase of construction in the Andes mountains in Chile and due to start operations in 2025 for 10 years, its 8.4-meter telescope will nightly scan the southern sky and collect images of the entire visible sky every 4 nights using a 3.2 Gigapixel camera, the largest imaging device ever built for astronomy. Automated detection and classification of celestial objects will be performed by sophisticated algorithms on high-resolution images to progressively produce an astronomical catalog eventually composed of 20 billion galaxies and 17 billion stars and their associated physical properties. In this paper, we briefly present the infrastructure deployed at the French Rubin data facility (operated by IN2P3 computing center, CC-IN2P3) to deploy the Rubin Science Platform, a set of web-based services to provide effective and convenient access to LSST data for scientific analysis. We describe the main services of the platform, the components that provide those services and our deployment model. We also present the Kubernetes-based infrastructure we are experimenting with for hosting the LSST astronomical catalog, a petabyte-scale relational database developed for the specific needs of the project. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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7. ÉMILE LÉPISSIER, A FRENCH ASTRONOMER OF MISFORTUNE WHO TAUGHT IN CHINA AND JAPAN.
- Author
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Tsuko Nakamura and Débarbat, Suzanne
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ASTRONOMERS ,ASTRONOMICAL observatories ,TEACHER educators ,SUDDEN death ,SCANDALS - Abstract
This paper presents the lifetime and achievements of a little-known French astronomer, Émile Lépissier, who contributed to the modernization of astronomy in China and Japan. He was recruited in 1854 by Paris Observatory as a Computer and later raised to an Astronome-adjoint. However, due to an unfair decision by the dictatorial Director, Le Verrier, Lépissier was forced to resign from the Observatory. Eventually he was dispatched to Beijing and taught French at the Tongwen Guan School from 1867 to early 1870. After leaving Beijing, Lépissier moved to Shanghai and in 1871 initiated one of the earliest French newspapers in China. But because of strong competition from another French newspaper, Lépissier had to abandon his publishing business in 1872. In that same year he landed in Yokohama, near Tokyo. Lépissier was then employed by the Japanese Government and began teaching mathematics and astronomy at a school that later evolved into the University of Tokyo. He also published an Almanach pour l'Année 1873 for foreigners, helped organize curricula and subjects at the school and advised the Government to establish a modern astronomical observatory. In 1874 Lépissier formally began teaching astronomy as a professor, but just three months later a sudden serious illness prevented him from continuing to teach. As a result, he retired from the school and sailed for France. After returning to Paris he soon passed away in poverty. Although Lépissier may have been an unsuccessful astronomer who suffered multiple misfortunes, we must appreciate his role as one of the founders of the early modern educational systems of China and Japan. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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8. The high energy X-ray probe (HEX-P): constraining supermassive black hole growth with population spin measurements.
- Author
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Piotrowska, J. M., Garcia, J. A., Walton, D. J., Beckmann, R. S., Stern, D., Ballantyne, D. R., Wilkins, D. R., Bianchi, S., Boorman, P. G., Buchner, J., Chen, C.-T., Coppi, P., Dauser, T., Fabian, A. C., Kammoun, E., Madsen, K., Mallick, L., Matt, G., Matzeu, G., and Nardini, E.
- Subjects
BLACK holes ,X-rays ,X-ray spectra ,ASTRONOMICAL observatories ,SUPERMASSIVE black holes - Abstract
Constraining the primary growth channel of supermassive black holes (SMBHs) remains one the most actively debated questions in the context of cosmological structure formation. Owing to the expected connection between SMBH spin parameter evolution and the accretion and merger history of individual black holes, population spin measurements offer a rare observational window into the cosmic growth of SMBHs. As of today, the most common method for estimating SMBH spin relies on modeling the relativistically broaden atomic profiles in the reflection spectrum observed in X-rays. In this paper, we study the observational requirements needed to confidently distinguish between the primary SMBH growth channels based on their distinct spin-mass distributions predicted by the Horizon-AGN cosmological simulation. Indoing so, we characterize outstanding limitations associated with the existing measurements and discuss the landscape of future observational campaigns which could be planned and executed with future X-ray observatories. We focus our attention on the High-Energy X-ray Probe (HEX-P), a proposed probe-class mission designed to serve the high- energy community in the 2030s. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
9. Revealing observatory networks through object stories: Instrumental networks.
- Author
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Akkermans, Emily, Wilder, Kelley, and Thompson, Samantha
- Subjects
IMAGE processing ,OBSERVATORIES ,SCIENTIFIC apparatus & instruments ,SCIENTIFIC expeditions ,ELECTRIC circuits ,ASTRONOMICAL observatories - Abstract
This paper presents three pieces that use objects, or object types, to reveal the material, personal, institutional and commercial networks that surrounded the introduction and successful use of instruments, systems and techniques. The objects explored are: the Hourly Signal Relay, used within the time signal system of the Royal Observatory, Greenwich, from the mid-nineteenth century; photographic glass plates from the British 1874 transit of Venus expeditions; and an electronic imaging tube, Lallemand's camera, developed in Paris and used at the Lick Observatory in California in the 1960s. Each story uses examples of failure as a means of highlighting a lack of robustness in or effort required to maintain these networks. Once created, however, such networks could, as the second two stories note, go on to develop and support alternative approaches, helping to create success from apparent failure. Nevertheless, complexity, failure and fragility have also led to the underrepresentation or obscurity of these objects in museum collections, until given focused attention in these studies. The paper forms part of a collection of articles: Revealing observatory networks through object stories. The other papers in the collection are 'Object itineraries', and 'Observatory audiences' and the genesis of the collection is discussed in the 'Introduction'. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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10. Surveying the Giant H ii Regions of the Milky Way with SOFIA. IV. Sgr D, W42, and a Reassessment of the Giant H ii Region Census.
- Author
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De Buizer, James M., Lim, Wanggi, Karnath, Nicole, Radomski, James T., and Bonne, Lars
- Subjects
CENSUS ,INFRARED astronomy ,ASTRONOMICAL observatories ,STAR clusters - Abstract
This is the fourth paper exploring the infrared properties of giant H ii regions with the FORCAST instrument on the Stratospheric Observatory For Infrared Astronomy (SOFIA). Our survey utilizes the census of 56 Milky Way giant H ii regions identified by Conti & Crowther, and in this paper we present the 20 and 37 ÎĽ m imaging data we obtained from SOFIA for sources Sgr D and W42. Based upon the SOFIA data and other multiwavelength data, we derive and discuss the detailed physical properties of the individual compact sources and subregions as well as the large-scale properties of Sgr D and W42. However, improved measurements have revealed much closer distances to both regions than previously believed, and consequently, both sources are not powerful enough to be considered giant H ii regions any longer. Motivated by this, we revisit the census of giant H ii regions, performing a search of the last two decades of literature to update each source with the most recent and/or most accurate distance measurements. Based on these new distance estimates, we determine that 14 sources in total (25%) are at sufficiently reliable and closer distances that they are not powerful enough to be considered giant H ii regions. We briefly discuss the observational and physical characteristics specific to Sgr D and W42 and show that they have properties distinct from the giant H ii regions previously studied as a part of this survey. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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11. Cândido Baptista de Oliveira and the "Forgotten Memoir": The First Plan of a National Astronomical Observatory After Brazilian Independence (1822-1831).
- Author
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Farias, Millena Souza
- Subjects
ASTRONOMICAL observatories ,SCIENTIFIC knowledge ,HISTORY of astronomy ,MATHEMATICIANS - Abstract
On February 1, 1828, the newspaper Diario Fluminense published in full the Plan for the establishment of an astronomical observatory in the city of Rio de Janeiro. The document was written by the Brazilian mathematician Cândido Baptista de Oliveira and substantiated the approval of the law determining the creation of the future Imperial Astronomical Observatory of Rio de Janeiro (IORJ). This paper discusses the influences embedded within Oliveira's project, by analyzing the appropriation of different scientific traditions gained during his training as a mathematician at the Observatory of the University of Coimbra and during his studies at French scientific institutions, such as the Polytechnic School and Paris Observatory. I argue that this project had a nationalistic ideal, imbued with the notions of progress and modernity, both effects of the ongoing circulation of people and scientific knowledge during the beginning of the nineteenth century. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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12. INDIAN INITIATIVES TO ESTABLISH 'WESTERN' ASTRONOMICAL OBSERVATORIES PRIOR TO INDEPENDENCE. 1: THE ARISTOCRATS.
- Author
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Orchiston, Wayne and Kapoor, R. C.
- Subjects
- *
ASTRONOMICAL observatories , *PATRONAGE , *ARISTOCRACY (Social class) , *ASTRONOMICAL observations , *INDIANS (Asians) , *NINETEENTH century , *GEOMAGNETISM ,PARTITION of India, 1947 - Abstract
This paper outlines the efforts at establishing observatories in India for modern astronomical observations made by aristocrats over the last century or so prior to Indian independence in 1947. The focus of this paper is therefore on three institutions only, the Royal Observatory at Lucknow, Trevandrum Observatory, and Nizamiah Observatory in Hyderabad. This demonstrates that the concept of 'patronage' was alive and well in nineteenth century India, just as it was in Britain, Europe and North America. These observatories primarily were established either to encourage educated Indians to gain a realistic knowledge of Western astronomy, or so that India itself could contribute to that body of research knowledge. One of these institutions, Nizamiah Observatory was India's sole observatory involved in the ambitious international Astrographic Catalogue and Carte du Ciel and Project. It is telling that quite early in its history this Observatory ended up with a university, while this fate later befell Trevandrum Observatory. It is notable that none of the observatories discussed in this paper has survived in its original form through to the present day as a forefront astronomical research facility. Moreover, relatively early in its history Trevandrum Observatory abandoned astronomy and shifted its focus to geomagnetism. Unlike the observatories discussed in the first paper in this series, none of the observatories reviewed in this paper was set up primarily to further Britain's colonial ambitions. All were local Indian initiatives, yet each received support, in one way or another, from British astronomers or observatories--so the colonial link was still there, but only as an underlying element. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
13. CARLOS BETTENCOURT FARIA'S DREAM: THE MULEMBA ASTRONOMICAL OBSERVATORY AT LUANDA IN ANGOLA.
- Author
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Almeida, Maria and Bonifácio, Vitor
- Subjects
ASTRONOMICAL observatories ,AUTODIDACTICISM ,ARTIFICIAL satellite tracking ,RADIO telescopes ,PORTUGUESE colonies ,COMMERCIAL drivers' licenses - Abstract
Mulemba Astronomical Observatory, later known as the Mulemba Space Centre was founded in 1958 on Luanda's outskirts in Angola, then an African Portuguese colony, by the polymath Carlos Mar Bettencourt Faria. Being, from all accounts, a charming and knowledgeable individual who was mainly self taught, he managed to build several radio telescopes, a solar observing station, a state-of-the-art electronics laboratory and a satellite tracking facility. Financial support was obtained from a variety of individuals, commercial companies, public institutions and from 1971 onwards Angola's national government. Faria's ambitious plans were nevertheless always thwarted or delayed by lack of funds. In 1973 data started to be collected at the solar station but the whirlwind of 1970s politics had a decisive impact in Angola. Faria's beautiful dream effectively ended when he was assassinated at the Observatory in 1976. In this paper we recall Carlos Bettencourt Faria's life and his battle against all odds to establish a professional-level astronomical observatory in Angola. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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14. An all-sky camera image classification method using cloud cover features.
- Author
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Li, Xiaotong, Wang, Baozhu, Qiu, Bo, and Wu, Chao
- Subjects
CLOUDINESS ,ASTRONOMICAL observatories ,CAMERAS ,AUTOMATIC classification ,RANDOM forest algorithms - Abstract
The all-sky camera (ASC) images can reflect the local cloud cover information, and the cloud cover is one of the first factors considered for astronomical observatory site selection. Therefore, the realization of automatic classification of the ASC images plays an important role in astronomical observatory site selection. In this paper, three cloud cover features are proposed for the TMT (Thirty Meter Telescope) classification criteria, namely cloud weight, cloud area ratio and cloud dispersion. After the features are quantified, four classifiers are used to recognize the classes of the images. Four classes of ASC images are identified: "clear", "inner", "outer" and "covered". The proposed method is evaluated on a large dataset, which contains 5000 ASC images taken by an all-sky camera located in Xinjiang (38.19 ∘ N, 74.53 ∘ E). In the end, the method achieves an accuracy of 96.58 % and F1_score of 96.24 % by a random forest (RF) classifier, which greatly improves the efficiency of automatic processing of the ASC images. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
15. H i galaxy signatures in the SARAO MeerKAT galactic plane survey − III. Unveiling the obscured part of the Vela Supercluster.
- Author
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Rajohnson, Sambatriniaina H A, Kraan-Korteweg, Renée C, Chen, Hao, Frank, Bradley S, Steyn, Nadia, Kurapati, Sushma, Pisano, D J, Staveley-Smith, Lister, Serra, Paolo, Goedhart, Sharmila, and Camilo, Fernando
- Subjects
- *
MEERKAT , *GALAXIES , *RADIO frequency , *ASTRONOMICAL observatories , *LARGE scale structure (Astronomy) , *RADIO astronomy - Abstract
We conducted a search for |$\textrm {H}\, \scriptstyle \mathrm{I}$| emission of the gas-rich galaxies in the Vela region (260° ≤ ℓ ≤ 290°, −2° ≤ b ≤ 1°) to explore the Vela Supercluster (VSCL) at V hel ∼ 18 000 |$\rm km\, s^{-1}$| , largely obscured by Galactic dust. Within the mostly Radio Frequency Interference-free band (250 < V hel < 25 000 |$\rm km\, s^{-1}$|) of MeerKAT, the analysis focuses on 157 hexagonally distributed pointings extracted from the South African Radio Astronomy Observatory MeerKAT Galactic Plane Survey located in the Vela region (Vela−SMGPS). These were combined into 10 contiguous mosaics, covering an ∼90 square degrees area. Among the 843 |$\textrm {H}\, \scriptstyle \mathrm{I}$| detected sources, 39 were previously discovered in the H i Parkes Zone of Avoidance survey (V hel < 12 000 |$\rm km\, s^{-1}$| ; rms ∼ 6 |$\rm mJy\, beam^{-1}$|). With the improved rms level of the Vela−SMGPS, i.e. 0.29–0.56 |$\rm mJy\, beam^{-1}$| , our study unveils nearly 12 times more detections (471 candidates) in that same velocity range. We furthermore could identify 187 galaxy candidates with an |$\textrm {H}\, \scriptstyle \mathrm{I}$| mass limit reaching |$\log (M_{\rm HI}/\rm {\rm M}_{\odot }) = 9.44$| in the VSCL velocity range V hel ∼ 19 500 ± 3500 |$\rm km\, s^{-1}$|. We find indications of two wall-like overdensities that confirm the original suspicion that these walls intersect at low latitudes around longitudes of ℓ ∼ 272°–278°. We also find a strong signature most likely associated with the Hydra/Antlia extension and evidence of a previously unknown narrow filament at V hel ∼ 12 000 |$\rm km\, s^{-1}$|. This paper demonstrates the efficiency of systematic |$\textrm {H}\, \scriptstyle \mathrm{I}$| surveys with the Square Kilometre Array (SKA) precursor MeerKAT, even in the most obscured part of the Zone of Avoidance. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
16. A short review on the pulsar magnetic inclination angles.
- Author
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Li, Biao‐Peng and Gao, Zhi‐Fu
- Subjects
RADIO telescopes ,ASTRONOMICAL observatories ,ANGLES ,MAGNETIC fields ,PULSARS - Abstract
The inclination angle χ between the magnetic and rotation axes of pulsars is an important parameter in pulsar physics. The changes in the inclination angle of a pulsar would lead to observable effects, such as changes in the pulse beam width and braking index of the star. In this paper, we perform a short review on the evolution of a pulsar's magnetic inclination angle, as well as the latest research progress. Using an alignment rotator model in a vacuum, we investigate the magnetic inclination angle change rates for 12 high‐braking index pulsars without a glitch, whose timing observations are obtained using the Nanshan 25‐m Radio Telescope at Xinjiang Astronomical Observatory. For our purpose, three representative pulsars J0157+6212, J1743−3150, and J1857+0526 are chosen and their rotation and inclination angle evolutions are further investigated. In the future, radio and x‐ray polarimetric observations will provide more information about the inclination angles of pulsars, which could help us understand the origin of the variations in χ of pulsars and shed light on the range of possibilities of pulsar magnetic field configuration. A continuous study of the pulsar inclination angle will provide an important window into additional physical processes at work in the young and highly magnetized pulsars. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
17. The Astroparticle Detectors Array—An Educational Project in Cosmic Ray Physics.
- Author
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Arcani, Marco, Conte, Elio, Monte, Omar Del, Frassati, Alessandra, Grana, Andrea, Guaita, Cesare, Liguori, Domenico, Nemolato, Altea Renata Maria, Pigato, Daniele, and Rubino, Elia
- Subjects
ULTRA-high energy cosmic rays ,COSMIC rays ,PHYSICS ,SPACE environment ,DETECTORS ,ASTRONOMICAL observatories ,SOLAR activity - Abstract
ADA, short for Astroparticle Detectors Array, is an educational project aiming to detect cosmic radiation and possibly high-energy particles known as ultra-high-energy cosmic rays (UHECRs) or even to spot a supernova event. Its working process is the same as that used in professional cosmic ray observatories: it consists of simple detectors spread over the entire Italian territory and beyond. The detectors are hosted among high schools, associations, and private astronomical observatories. ADA has been operating since 2013 and was brought about with the intention of promoting astroparticle physics to any given level of outreach. Furthermore, ADA is becoming an interesting tool not only for teachers but also for independent and keen scientists. Over the years, we have discovered the importance of having a long series of data for studying the relation between and among cosmic rays, weather, and space weather and to investigate the main cause of oscillations in cosmic ray data. In this paper, we show what we find to be the most compelling results, such as the beautiful symmetry of the behavior between muons and the atmospheric temperature and, likewise, the evident anti-correlation between the intensity of the muons at ground level compared with solar activity. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
18. Polarimetric Reverberation Mapping in Medium-Band Filters.
- Author
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Shablovinskaya, Elena, Popović, Luka Č., Uklein, Roman, Malygin, Eugene, Ilić, Dragana, Ciroi, Stefano, Oparin, Dmitry, Crepaldi, Luca, Slavcheva-Mihova, Lyuba, Mihov, Boyko, and Nikolov, Yanko
- Subjects
ACTIVE galactic nuclei ,ASTRONOMICAL observatories - Abstract
Earlier, we suggested the "reload" concept of the polarimetric reverberation mapping of active galactic nuclei (AGN), proposed for the first time more than 10 years ago. We have successfully tested this approach of reverberation mapping of the broad emission line on the galaxy Mrk 6. It was shown that such an idea allows one to look at the AGN central parsec structure literally in a new light. However, the method originally assumed the use of spectropolarimetric observations, expensive in terms of telescope time, and implemented on rare large telescopes. Currently, we propose an adaptation of the polarimetric reverberation mapping of broad lines in medium-band filters following the idea of the photometric reverberation mapping, when filters are selected so that their bandwidth is oriented to the broad line and the surrounding continuum near. In this paper, we present the progress status of such monitoring conducted jointly at the Special astrophysical observatory and Asiago Cima Ekar observatory (OAPd/INAF) with support from Rozhen National Astronomical Observatory (NAO), some first results for the most frequently observed AGNs Mrk 335, Mrk 509, and Mrk 817, and the discussion of the future perspectives of the campaign. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
19. علم الفلك في التصور العثماني.
- Author
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شیماء جاسم البدر
- Subjects
MINIATURE painting ,CLIMATE change ,ASTRONOMICAL observatories ,RITES & ceremonies ,HUMAN beings ,ASTRONOMICAL photography - Abstract
Copyright of Athar alrafedain is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2023
20. Shared nomenclature and identifiers for telescopes and instruments.
- Author
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Perret, Emmanuelle, Louys, Mireille, Buga, Mihaela, and Lesteven, Soizick
- Subjects
GEOGRAPHIC information systems ,ASTRONOMICAL observatories ,TELESCOPES ,DATA analysis - Abstract
In the context of sharing public data, science results are expected to be reproducible and therefore we need full traceability of the origin of the data. On the documentalist side, there is a need to relate instrumental origins to the published data. We propose to define a shared nomenclature to index each publication with unique designations for facilities, telescopes and instruments which could benefit from the Virtual Observatory work on semantics. This would help the documentalists to check the consistency of the instrument description in publications or make it more explicit. Observation period, data quality and spectral coverage, for instance, may be checked by referencing a global instrumentation service which gathers the nominal observation parameters for the telescope/facility/instrument involved. Based on this indexation mechanism, then the bibliographic metrics for telescope/ instrument usage would be easy to compute, and tracking services like the ESO telescope bibliography database (TelBib) or others would be easier to feed. This paper traces the existing initiatives and gives the example of a facility description framework reusing Virtual Observatory metadata which could be fed by the community. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
21. Reconstruction of geomagnetic activity and near-Earth interplanetary conditions over the past 167 yr -- Part 4: Near-Earth solar wind speed, IMF, and open solar flux.
- Author
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Lockwood, M., Nevanlinna, H., Barnard, L., Owens, M. J., Harrison, R. G., Rouillard, A. P., and Scott, C. J.
- Subjects
SOLAR wind ,GEOMAGNETISM ,NEAR-earth interplanetary dust ,WIND speed measurement ,INTERPLANETARY magnetic fields ,MAGNETIC flux ,ASTRONOMICAL observatories - Abstract
In the concluding paper of this tetralogy, we here use the different geomagnetic activity indices to reconstruct the near-Earth interplanetary magnetic field (IMF) and solar wind flow speed, as well as the open solar flux (OSF) from 1845 to the present day. The differences in how the various indices vary with near-Earth interplanetary parameters, which are here exploited to separate the effects of the IMF and solar wind speed, are shown to be statistically significant at the 93% level or above. Reconstructions are made using four combinations of different indices, compiled using different data and different algorithms, and the results are almost identical for all parameters. The correction to the aa index required is discussed by comparison with the Ap index from a more extensive network of mid-latitude stations. Data from the Helsinki magnetometer station is used to extend the aa index back to 1845 and the results confirmed by comparison with the nearby St Petersburg observatory. The optimum variations, using all available long-term geomagnetic indices, of the near-Earth IMF and solar wind speed, and of the open solar flux, are presented; all with ±2σ uncertainties computed using the Monte Carlo technique outlined in the earlier papers. The open solar flux variation derived is shown to be very similar indeed to that obtained using the method of Lockwood et al. (1999). [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
22. A bibliometric study of research output of ISRO's space science and exploration missions.
- Author
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Ummer, Rehana and Rajgoli, Iqbalahmad U.
- Subjects
- *
SPACE sciences , *SPACE exploration , *BIBLIOMETRICS , *INFORMATION resources , *ASTRONOMICAL observatories - Abstract
Chandrayaan-1 and Chandrayaan-2, the Indian Mars Orbiter Mission (MOM), and a multi-wavelength astronomical observatory (AstroSat) are the missions launched by the Indian Space Research Organisation (ISRO) under the broader category of space science and exploration. The results generated from the periodically released data from these missions, are published in the form of journal articles, conference papers, The Astronomer's Telegrams, GRB Coordinates Network circulars, etc. The goal of this study is a bibliometric analysis of 592 journal articles on ISRO's four space science and exploration missions which were published between 2002 and 2021 (20 years). The Web of Science Core collection database and Google Scholar are used to retrieve the data needed for the study. Bibliometric indicators like mission-wise distribution of articles; year-wise distribution of articles, relative growth rate and doubling time of publications; prolific authors; leading institutions; international collaboration; highly ranked journals; highly cited articles and keyword occurrences were considered for analysis. The doubling time of publications of those missions which yielded the highest number of articles were separately calculated using an exponential equation and built in algorithms in Python. Advanced data visualization tool such as VosViewer was used for generating the network maps. The bibliometric analysis revealed the usage of mission output data not only by ISRO scientists but also by academia, research labs, etc. Overall, the study can be considered as a comprehensive reference source for information on research trends related to the four Indian space science and exploration missions. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
23. Photometric and Spectroscopic Analysis of the SX Phe Star BL Cam.
- Author
-
Abdel-Sabour, M., Nouh, M. I., Shokry, A., Hamed, G. M., Ismail, H. A., Takey, A., Ata, S. A., and Zead, I.
- Subjects
PULSATING stars ,ASTRONOMICAL observatories ,ATMOSPHERIC models ,FOURIER analysis ,STAR observations ,LIGHT curves ,ASTRONOMICAL photometry ,STELLAR atmospheres - Abstract
In the present paper, we report the photometric and spectroscopic observations of the pulsating star BL Cam obtained by the 1.88 m telescope at the Kottamia astronomical observatory (KAO). Fourier analysis of the light curves indicates one frequency, 25.14427 c/d, with harmonics 51.112 c/d, 33.388 c/d, and 17.72464 c/d. The frequency of 31-32 c/d reported in the literature is not detected in our data except for one close to 33.3882934 c/d. A total of 55 new times of maximum light have been presented. A new value of (1/P) dP/dt is estimated using the O-C diagram based on all newly obtained times of maximum light combined with those taken from the literature, assuming the periods are decreasing and changing smoothly. Using model atmosphere analysis, we computed the effective temperature and surface gravity as T
eff = 7625 ± 300 K and logg = 4.30 ± 0.37. The bolometric magnitude Mbol = 2.335, radius R = 1.69 R⨀ , luminosity L = 0.957 L⨀ , the mass M = 1.68M⨀ , and pulsation constant Q = 0.025 days. Locations of the star on the M-R and M-L diagrams indicate that it is close to the ZAMS track and is an unevolved star. [ABSTRACT FROM AUTHOR]- Published
- 2022
- Full Text
- View/download PDF
24. Carl Friedrich Gauss and the Gauss Society: a brief overview.
- Author
-
Wittmann, Axel D.
- Subjects
ASTRONOMICAL observatories ,GEODETIC astronomy ,GEODESY ,SCIENTISTS ,ASTRONOMY - Abstract
Carl Friedrich Gauss (1777–1855) was one of the most eminent scientists of all time. He was born in Brunswick, studied in Göttingen, passed his doctoral examination in Helmstedt, and from 1807 until his death, was the director of the Göttingen Astronomical Observatory. As a professor of astronomy, he worked in the fields of astronomy, mathematics, geodesy, and physics, where he made world-famous and lasting contributions. In his honour, and to preserve his memory, the Gauss Society was founded in Göttingen in 1962. The present paper aims to give nonspecialists a brief introduction into the life of Gauss and an introduction into the Gauss Society and its history. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
25. W. M. Keck observatory instrumentation status and future direction.
- Author
-
Kassis, Marc, Allen, Steven L., Alverez, Carlos, Baker, Ashley, Banyal, Ravinder K., Bertz, Robert, Beichman, Charles, Brown, Aaron, Brown, Matthew, Bundy, Kevin, Cabak, Gerald, Cetre, Sylvain, Chin, Jason, Chun, Mark R., Cooke, Jeff, Delorme, Jacques, Deich, William, Dekany, Richard G., Devenot, Mark, and Doppmann, Greg
- Subjects
- *
OBSERVATORIES , *COOPERATIVE research , *ASTRONOMICAL observatories , *ADAPTIVE optics , *STRATEGIC planning - Abstract
Since the start of science operations in 1993, the twin 10‐m W. M. Keck Observatory (WMKO) telescopes have continued to maximize their scientific impact and to produce transformative discoveries that keep the observing community on the frontiers of astronomical research. Upgraded capabilities and new instrumentation are provided through collaborative partnerships with Caltech, the University of California, and the University of Hawaii instrument development teams along with industry and other organizations. The observatory adapts and responds to the observers' evolving needs as defined in the observatory's strategic plan periodically refreshed in collaboration with the science community. This paper is an overview of the instrumentation projects that range from commissioning to early conceptual stages. An emphasis is placed on the detector, detector controllers, and capability needs that are driven by the desired future technology defined in the 2022 strategic plan. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
26. Methodology for the observation of radio sources using Ku‐band compact radio telescopes.
- Author
-
Galeano, David, Quintero, Edwin A., and Salazar, Miguel A.
- Subjects
RADIO telescopes ,RADIO waves ,RADIO astronomy ,BRIGHTNESS temperature ,ASTRONOMICAL observatories ,DIRECT broadcast satellite television ,RADIO sources (Astronomy) - Abstract
Given the rise of satellite television, radio telescopes in the Ku‐band (12–18 GHz) constitute a potential alternative to introduce low‐scale astronomical observatories and amateur astronomers to radio astronomy. In this paper, we show a methodology for the calibration of Ku‐band radio telescopes and the evaluation of the techniques used for the observation of celestial bodies in this frequency range. To reduce the pointing error, we present a method of observation through matrix windows around the Sun. By observing the solar transits, our methodology allows to determine the system temperature, the beamwidth, the gain, the effective area, and the efficiency of the radio telescope. In addition, we developed the Compact Radio Telescope (CRT) software, designed to perform the calibration, and carry out observations. We tested our methodology with the Ku‐band radio telescope of the Observatorio Astronómico of the Universidad Tecnológica de Pereira (OAUTP), Colombia. After observing the Sun and the Moon, we obtained a brightness temperature of 8,600 ± 800 K and 240 ± 50 K, and radiation fluxes of 2,970,000 ± 690,000 Jy and 55,000 ± 10,000 Jy, respectively. These observations demonstrated the usefulness of our methodology and CRT software in the calibration of compact Ku‐band radio telescopes for the observation of celestial bodies in radio waves. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
27. Developments of Space Debris Laser Ranging Technology Including the Applications of Picosecond Lasers.
- Author
-
Zhang, Haifeng, Long, Mingliang, Deng, Huarong, Cheng, Shaoyu, Wu, Zhibo, Zhang, Zhongping, Zhang, Ali, and Sun, Jiantao
- Subjects
LASER ranging ,SPACE debris ,LASERS ,LASER pulses ,ASTRONOMICAL observatories ,TELESCOPES ,RADAR cross sections - Abstract
Debris laser ranging (DLR) is receiving considerable attention as an accurate and effective method of determining and predicting the orbits of space debris. This paper reports some technologies of DLR, such as the high pulse repetition frequency (PRF) laser pulse, large-aperture telescope, telescope array, multi-static stations receiving signals. DLR with a picosecond laser at the Shanghai Astronomical Observatory is also presented. A few hundred laps of space debris laser-ranging measurements have been made. A double-pulse picosecond laser with an average power of 4.2 W, a PRF of 1 kHz, and a wavelength of 532 nm has been implemented successfully in DLR, it's the first time that DLR technology has reached a ranging precision at the sub-decimeter level. In addition, the characteristics of the picosecond-pulse-width laser transmission with the advantages of transmission in laser ranging were analyzed. With a mode of the pulse-burst picosecond laser having high average power, the DLR system has tracked small debris with a radar cross-section (RCS) of 0.91 m
2 at a ranging distance up to 1726.8 km, corresponding to an RCS of 0.1 m2 at a distance of 1000 km. These works are expected to provide new technologies to further improve the performance of DLR. [ABSTRACT FROM AUTHOR]- Published
- 2021
- Full Text
- View/download PDF
28. CMOS-based observation of Resident Space Objects using short-exposure stacking mode.
- Author
-
Zhu, Zheng-Hai, Zheng, Jing-Hui, Luo, Hao, Chen, Guo-Ping, Wang, Wei, Mao, Yin-Dun, Wu, Wen-Tang, and Wang, Kun-Peng
- Subjects
- *
SPACE surveillance , *ASTRONOMICAL observatories , *ORBITS (Astronomy) , *STANDARD deviations , *ARTIFICIAL satellites , *SPACE debris - Abstract
To meet the growing demand for the surveillance of resident space objects, the Shanghai Astronomical Observatory has developed a new observation method for monitoring resident space objects using a high frame rate astronomical CMOS camera, called the short-exposure stacking mode. This method can be used to observe objects of various orbit types with high observation accuracy. This paper describes the implementation of this new method of RSO observation, and the observation experiment of one MEO satellite and two GEO satellites using this method with a 40 cm telescope, the observation system has a 0.5 ° × 0.5 ° field of view. The observation results show that the accuracy of the sensor calibration is 0.3 - 0.4 arc-second. Compared with the external precision ephemeris, the standard deviation of the residual differences is better than 0.5 arc-second, which means that the precise orbit of space objects can be obtained with enough observation. And compared with the method that uses drift scan CCD, the observation time efficiency of the short-exposure stacking mode is better. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
29. Improved Orbit and Mass of the Binary Star 61 Cyg Based on Photographic Observations at Pulkovo.
- Author
-
Shakht, N., Gorshanov, D., and Vasilkova, O.
- Subjects
BINARY star orbits ,BINARY star mass ,ASTRONOMICAL photography ,ASTRONOMICAL observations ,ASTRONOMICAL observatories - Abstract
Observations of stars close to the sun which, in terms of their physical properties, are possible objects for space missions aimed at searching for planetary components, are made at the Pulkovo Observatory. In this paper we present new orbital elements for the binary star 61 Cyg derived from long-term series of observations at Pulkovo including current data on this star. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
30. Real-Time Condition Assessment of RAPTOR Telescope Systems.
- Author
-
Stull, Christopher J., Taylor, Stuart G., Wren, James, Mascareñas, David L., and Farrar, Charles R.
- Subjects
TELESCOPES ,ASTRONOMICAL instruments ,ASTRONOMICAL observatories ,ASTRONOMY ,ASTROPHYSICS - Abstract
The RAPid Telescopes for Optical Response (RAPTOR) observatory network consists of several ground-based, autonomous, robotic, astronomical observatories primarily designed to search for astrophysical transients called gamma-ray bursts. To make these observations, however, the RAPTOR telescopes must remain in peak operating condition at a high duty-cycle. Currently, the telescopes are maintained in an ad hoc manner, often in a run-to-failure mode. The required maintenance logistics are further complicated by the fact that many of the observatories are situated in remote locations. To ameliorate this situation, an effort has been initiated to develop a structural health monitoring (SHM) system capable of real-time, remote assessment of the RAPTOR telescopes. This paper summarizes the results from that effort. Common damage scenarios are identified to guide the instrumentation of the telescope system. A comprehensive analysis of the data acquired during experimental testing is then presented, highlighting the capability of the SHM system to discern between damaged and undamaged states. The paper concludes with a summary of future planned refinements for the RAPTOR SHM system. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
31. Development of Solar Observations in Bulgaria: New 30-cm Chromospheric Telescope.
- Author
-
Tsvetkov, Ts. and Petrov, N.
- Subjects
SOLAR telescopes ,SOLAR cell design ,ASTRONOMICAL observatories - Abstract
The development of solar observations during the last decades and the growing influence of space-based telescopes turns the ground-based monitoring of the Sun into complementary activity. Nevertheless, new solar telescopes continue to be established as they excel space-borne instruments with the immediate access to the received data and relatively low completion cost. In 2019 a project for establishing a new 30-cm solar telescope in the National Astronomical Observatory Rozhen (Bulgaria) was launched. This paper summarizes the primary goals and objectives of the telescope as well as its stage of construction. [ABSTRACT FROM AUTHOR]
- Published
- 2021
32. Measurement of the atmospheric muon neutrino energy spectrum with IceCube in the 79- and 86-String configuration.
- Author
-
Ruhe, T., Scheriau, F., and Schmitz, M.
- Subjects
MUONIC neutrino ,NEUTRINO detectors ,NEUTRINO astrophysics ,ASTRONOMICAL observatories ,OPTICAL modulators - Abstract
IceCube is a neutrino telescope with an instrumented volume of one cubic kilometer. A total of 5160 Digital Optical Modules (DOMs) is deployed on 86 strings forming a three dimensional detector array. Although primarily designed for the detection of neutrinos from astrophysical sources, the detector can be used for spectral measurements of atmospheric neutrinos. These spectral measurements are hindered by a dominant background of atmospheric muons. State-of-the-art techniques from Machine Learning and DataMining are required to select a high-purity sample of atmospheric neutrino candidates. The energy spectrum of muon neutrinos is obtained from energy-dependent input variables by utilizing regularized unfolding. The results obtained using IceCube in the 79- and 86-string configuration are presented in this paper. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
33. ARMAGH OBSERVATORY --HISTORIC BUILDING INFORMATION MODELLING FOR VIRTUAL LEARNING IN BUILDING CONSERVATION.
- Author
-
Murphy, M., Chenaux, A., Keenaghan, G., GIbson, V., Butler, J., and Pybusr, C.
- Subjects
ASTRONOMICAL observatories ,BUILDING information modeling ,PRESERVATION of architecture - Abstract
In this paper the recording and design for a Virtual Reality Immersive Model of Armagh Observatory is presented, which will replicate the historic buildings and landscape with distant meridian markers and position of its principal historic instruments within a model of the night sky showing the position of bright stars. The virtual reality model can be used for educational purposes allowing the instruments within the historic building model to be manipulated within 3D space to demonstrate how the position measurements of stars were made in the 18th century. A description is given of current student and researchers activities concerning on-site recording and surveying and the virtual modelling of the buildings and landscape. This is followed by a design for a Virtual Reality Immersive Model of Armagh Observatory use game engine and virtual learning platforms and concepts. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
34. Astrophysics: Time for an Arab astronomy renaissance.
- Author
-
Guessoum, Nidhal
- Subjects
ARAB astronomy ,OBSERVATION decks ,ASTRONOMICAL observatories ,TELESCOPES ,ASTRONOMERS - Abstract
The author presents his opinion on the state of Arab astronomy. The author is appalled at the lack of government initiative to encourage astronomy in the region despite enormous wealth in the region. The author urges the local governments to give grants to develop astronomical observatories in the region since the region has several observation points of interest. The author opines that government encouragement would go a long way in reviving Arab astronomy and encourage Arab astronomers.
- Published
- 2013
- Full Text
- View/download PDF
35. Radio pulsar beam geometry down to the 100-MHz band: 76 additional sources within the Arecibo Sky.
- Author
-
Rankin, Joanna, Wahl, Haley, Venkataraman, Arun, and Olszanski, Timothy
- Subjects
- *
PULSARS , *RADIO astronomy , *ASTRONOMICAL observatories , *GEOMETRIC modeling ,PULSAR detection - Abstract
This paper provides analyses of the emission beam structure of 76 'B'-named pulsars within the Arecibo sky. Most of these objects are included in both the Gould & Lyne and LOFAR High Band surveys and thus complement our other works treating various parts of these populations. These comprise a further group of mostly well-studied pulsars within the Arecibo sky that we here treat similarly to those in Olszanski et al. – and extend our overall efforts to study all of the pulsars in both surveys. The analyses are based on observations made with the Arecibo Telescope at 327 MHz and 1.4 GHz. Many have been observed at frequencies down to 100 MHz using either LOFAR or the Pushchino Radio Astronomy Observatory as well as a few with the Long Wavelength Array at lower frequencies. This work uses the Arecibo observations as a foundation for interpreting the low frequency profiles and emission-beam geometries. We attempt to build quantitative geometric emission-beam models using the core/double-cone topology, while reviewing the evidence of previous studies and arguments for previous classifications on these sources. These efforts were successful for all but two pulsars, and interesting new subpulse modulation patterns were identified in a number of the objects. We interpret the Arecibo pulsar population in the context of the entire population of 'B' pulsars. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
36. Semi-analytical configuration optimization of geocentric gravitational wave observatory.
- Author
-
Jia, Feida, Li, Xiangyu, Qiao, Dong, and Zhou, Xingyu
- Subjects
- *
STRUCTURAL optimization , *OBSERVATORIES , *SPACE sciences , *GRAVITATIONAL waves , *SPACE astronomy , *MATHEMATICAL optimization , *ASTRONOMICAL observatories - Abstract
The detection of gravitational waves (GWs) from space is a hot topic in astronomy and space science, as the Space Gravitational Wave Observatory can detect low-frequency GWs from various sources. The long-term stability of the configuration of GW observatories is the key to the success of GWs detection, which challenges the configuration design and optimization. This paper innovatively proposes an semi-analytical double-layer iterative optimization algorithm (DLI) to solve the geocentric configuration optimization problem. First, an iterative method with gradient information of breathing angle, which is compensated by its standard deviation, is introduced as the inner iteration layer. Then, the outer iterative layer executes the initial value update process via the selection of the constructed candidates with smallest arm length variation rate, until the maximum breathing angle variation converges to the preset accuracy. The proposed method is applied to optimize the nominal configuration of TianQin mission. The results shows that DLI can reduce about 99% computation duration compared with the numerical optimization method. Furthermore, the influence of initial configuration elements on stability parameters are analyzed, providing better alternation for geocentric GWs detection missions. • A semi-analytical configuration optimization of the GWs observatory is proposed. The efficiency is improved more than 100 times. • The inner iteration is realized with the compensated breathing angles as the gradient. • The effects of orbital elements on the configuration performance are analyzed. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
37. Over seven decades of solar microwave data obtained with Toyokawa and Nobeyama Radio Polarimeters.
- Author
-
Masumi Shimojo and Kazumasa Iwai
- Subjects
- *
POLARISCOPE , *DATA libraries , *ASTRONOMICAL observatories , *SERVER farms (Computer network management) , *ASTRONOMY - Abstract
Monitoring observations of solar microwave fluxes and their polarization began in Japan during the 1950s at Toyokawa and Mitaka. At present (April 2022), monitoring observations continues with the Nobeyama Radio Polarimeters (NoRP) at the Nobeyama campus of the National Astronomical Observatory of Japan (NAOJ). In this paper, we present a brief history of the solar microwave monitoring observations preceding those now carried out by NoRP. We then review the solar microwave flux and polarization measurements obtained at Toyokawa and Nobeyama, and their metadata. The datasets are publicly provided by the Solar Data Archive System (SDAS) operated by the Astronomy Data Center of the NAOJ, via http (https://solar.nro.nao.ac.jp/norp/) and FTP (ftp://solar -pub.nao.ac.jp/pub/nsro/norp/) protocols. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
38. A detailed X-ray investigation of ζ Puppis: I. The dataset and some preliminary results.
- Author
-
Nazé, Y., Flores, C. A., and Rauw, G.
- Subjects
ASTRONOMICAL observations ,ASTRONOMICAL observatories ,X-ray diffractometers ,MATHEMATICAL models ,WAVELENGTHS - Abstract
Aims. One of the closest and brightest massive stars, ζ Puppis, was the first early-type object observed by the current generation of X-ray observatories. These observations provided some surprising results, partly confirming the theoretical predictions while simultaneously unveiling some problematic mismatches with expectations. In this series of papers, we perform a thorough study of ζ Puppis in X-rays, using a decade of XMM-Newton observations. Methods. The star ζ Puppis was observed 18 times by XMM-Newton, totaling 1 Ms in exposure. This provides the highest quality high-resolution X-ray spectrum of a massive star to date, as well as a perfect dataset for studying X-ray variability in an "archetype" object. Results. This first paper reports on the data reduction of this unique dataset and provides a few preliminary results. On the one hand, analysis of EPIC low-resolution spectra shows the star to have a remarkably stable X-ray emission from one observation to the next. On the other hand, fitting by a wind model of individual line profiles recorded by RGS confirms the wavelength dependence of the line morphology. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
39. Correction: Fu, N.; et al. The Two-Parts Step-by-Step Ionospheric Assimilation Based on Ground-Based/Spaceborne Observations and Its Verification. Remote Sens. 2019, 11, 1172.
- Author
-
Fu, Naifeng, Guo, Peng, Wu, Mengjie, Huang, Yong, Hu, Xiaogong, and Hong, Zhenjie
- Subjects
SPACE-based radar ,ASTRONOMICAL observatories - Abstract
The Two-Parts Step-by-Step Ionospheric Assimilation Based on Ground-Based/Spaceborne Observations and Its Verification. Therefore, we apply for an adjustment to the order of the first affiliation and the second affiliation in this paper, which makes the authors' affiliations and emails' list displayed as follows: 1 Fu N., Guo P., Wu M., Huang Y., Hu X., Hong Z. The Two-Parts Step-by-Step Ionospheric Assimilation Based on Ground-Based/Spaceborne Observations and Its Verification. [Extracted from the article]
- Published
- 2019
- Full Text
- View/download PDF
40. Polvere di stelle: The Italian platform for data-sharing and data-preserving of modern and ancient astronomical resources.
- Author
-
Gargano, Mauro, Gasperini, Antonella, Schiavone, Luisa, and Brunetti, Francesca
- Subjects
DATABASE design ,ASTRONOMICAL observations ,METADATA ,ASTRONOMERS ,ASTRONOMICAL observatories - Abstract
Abstract. Polvere di stelle (Stardust) is the web portal of the National Institute for Astrophysics (INAF) dedicated to the Italian astronomical libraries, archives and museums. It offers different tools and databases created to support astronomical research and increase the value of one of the richest astronomical heritages in the world. In a single virtual space one can find useful tools for sharing digital resources and other services for current research. Besides the OPAC, consisting of bibliographic data of ancient and modern books and serials, the portal offers to astronomers, scholars, students, amateur astronomers and historians of science the possibility to search at the same time other databases: manuscripts, instruments, archival documents and biographies of astronomers. Furthermore, a digital showcase of rare books plays a relevant role in the portal. This paper illustrates the ongoing developments and perspectives of Polvere di stelle. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
41. Astronomy in Chile: Assessment of scientific productivity through a bibliometric analysis.
- Author
-
Cortes, Rodrigo, Depoortere, Denise, and Malaver, Lucina
- Subjects
BIBLIOMETRICS ,ASTRONOMICAL observatories ,ASTRONOMICAL observations ,ASTROPHYSICS ,CITATION analysis - Abstract
The skies of Northern Chile are considered among the best in the world for astronomy due to their geographical, climatic and atmospheric conditions. In fact, during the last several decades, a great number of astronomical observatories have been built by space research institutions devoted to space research, turning Chile into one of the countries with the greatest astronomical observation capacity in the world. Consequently, it is relevant to explore and assess the development of astronomy in Chile during the last ten years (2005-2015), carrying out a bibliometric analysis to extract traditional metrics, complemented with alternative metrics, to identify the Chilean production and scientific contribution of research in this field of knowledge. The results from traditional metrics, based on the information obtained in the Web of Science (WoS) database analyzed through InCites for the Astronomy & Astrophysics category indicate a sustained increase of the scientific production for the discipline during the last ten years. In particular, the Normalized Citation Impact of organizations and institutions conducting research in Chile is above the worldwide average. On the other hand, the alternative metrics, including for instance, the altmetrics types presented by the SCOPUS database, reflect that the Chilean research impact is much lower in the context of social networks. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
42. Diurnal and nocturnal cloud segmentation of all-sky imager (ASI) images using enhancement fully convolutional networks.
- Author
-
Shi, Chaojun, Zhou, Yatong, Qiu, Bo, He, Jingfei, Ding, Mu, and Wei, Shiya
- Subjects
IMAGE intensifiers ,PIXELS ,OPTICAL astronomy ,ASTRONOMICAL observatories - Abstract
Cloud segmentation plays a very important role in astronomical observatory site selection. At present, few researchers segment cloud in nocturnal all-sky imager (ASI) images. This paper proposes a new automatic cloud segmentation algorithm that utilizes the advantages of deep-learning fully convolutional networks (FCNs) to segment cloud pixels from diurnal and nocturnal ASI images; it is called the enhancement fully convolutional network (EFCN). Firstly, all the ASI images in the data set from the Key Laboratory of Optical Astronomy at the National Astronomical Observatories of Chinese Academy of Sciences (CAS) are converted from the red–green–blue (RGB) color space to hue saturation intensity (HSI) color space. Secondly, the I channel of the HSI color space is enhanced by histogram equalization. Thirdly, all the ASI images are converted from the HSI color space to RGB color space. Then after 100 000 iterative trainings based on the ASI images in the training set, the optimum associated parameters of the EFCN-8s model are obtained. Finally, we use the trained EFCN-8s to segment the cloud pixels of the ASI image in the test set. In the experiments our proposed EFCN-8s was compared with four other algorithms (OTSU, FCN-8s, EFCN-32s, and EFCN-16s) using four evaluation metrics. Experiments show that the EFCN-8s is much more accurate in cloud segmentation for diurnal and nocturnal ASI images than the other four algorithms. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
43. Isodensity analysis of comets using the collection of digitized Engelhardt Astronomical Observatory photographic plates.
- Author
-
Nefedyev, Yury, Andreev, Alexey, and Hudec, Rene
- Subjects
ASTRONOMICAL observatories ,METEOR showers ,GEODETIC astronomy ,COMETS ,DIGITAL images ,PHOTOGRAMMETRY ,DIGITAL image processing - Abstract
The field of astronomy dealing with comets is an important component of modern space investigations. This applies both to the study of physical, chemical, and evolutionary parameters and to the determination of connections between meteor showers and their parental bodies. This paper considers the isodensity analysis of Arend‐Roland, 45P/Honda, and Bennett comets using the measurements of photographic plates performed at Engelhardt Astronomical Observatory. On the basis of a software aimed at analyzing the brightness of digital images, structural models for three comets were developed. The isophotes of their nuclei, comas, and tails were determined as well. As the cometary nuclei are the elements of dynamical evolution and processes in the Solar Nebula, the study of a digital database on comets will allow refining the theory of their formation and evolution. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
44. Photometric Studies of the Seyfert Galaxies NGC 3516, NGC 5548, NGC 3227, NGC 4051, NGC 4151, and NGC 7469.
- Author
-
Shomshekova, S. A., Denissyuk, E. K., Valiullin, R. R., Reva, I. V., and Kusakin, A. V.
- Subjects
SEYFERT galaxies ,LIGHT curves ,ASTRONOMICAL observatories ,ASTROPHYSICS - Abstract
Results of photometric observations of the Seyfert galaxies NGC 3516, NGC 5548, NGC 3227, NGC 4051, NGC 4151 and NGC 7469 made on the east 1-m telescope (Tyan-Shan Astronomical Observatory of the V. G. Fesenkov Institute of Astrophysics) are presented in this paper. The observations were made in the three filters BVR, from April 9, 2014 for NGC 3516, NGC 5548, and NGC 3227, and since 2013 for NGC 4051, NGC 4151 and NGC 7469. The observational data yielded estimates of the brightness of the central regions of the Seyfert galaxies and light curves were plotted. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
45. Overview of the distributed image processing infrastructure to produce the Legacy Survey of Space and Time.
- Author
-
Hernandez, Fabio, Beckett, George, Clark, Peter, Doidge, Matt, Jenness, Tim, Karavakis, Edward, Le Boulc'h, Quentin, Love, Peter, Mainetti, Gabriele, Noble, Timothy, White, Brandon, and Yang, Wei
- Subjects
IMAGE processing ,SERVER farms (Computer network management) ,ALGORITHMS ,ASTRONOMICAL observatories ,ELECTRONIC data processing - Abstract
The Vera C. Rubin Observatory is preparing to execute the most ambitious astronomical survey ever attempted, the Legacy Survey of Space and Time (LSST). Currently the final phase of construction is under way in the Chilean Andes, with the Observatory's ten-year science mission scheduled to begin in 2025. Rubin's 8.4-meter telescope will nightly scan the southern hemisphere collecting imagery in the wavelength range 320–1050 nm covering the entire observable sky every 4 nights using a 3.2 gigapixel camera, the largest imaging device ever built for astronomy. Automated detection and classification of celestial objects will be performed by sophisticated algorithms on high-resolution images to progressively produce an astronomical catalog eventually composed of 20 billion galaxies and 17 billion stars and their associated physical properties. In this article we present an overview of the system currently being constructed to perform data distribution as well as the annual campaigns which reprocess the entire image dataset collected since the beginning of the survey. These processing campaigns will utilize computing and storage resources provided by three Rubin data facilities (one in the US and two in Europe). Each year a Data Release will be produced and disseminated to science collaborations for use in studies comprising four main science pillars: probing dark matter and dark energy, taking inventory of solar system objects, exploring the transient optical sky and mapping the Milky Way. Also presented is the method by which we leverage some of the common tools and best practices used for management of large-scale distributed data processing projects in the high energy physics and astronomy communities. We also demonstrate how these tools and practices are utilized within the Rubin project in order to overcome the specific challenges faced by the Observatory. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
46. KAGRA and beyond: Gravitational wave physics and astronomy. Part 1.
- Author
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Itoh, Yousuke
- Subjects
GRAVITATIONAL waves ,ASTRONOMY ,ASTRONOMICAL observatories ,ELECTROMAGNETIC waves ,NEUTRON stars - Abstract
An editorial is presented on Gravitational wave physics and astronomy in Kamioka Gravitational Wave Detector (KAGRA) observatory. Topics include electromagnetic wave follow-up campaigns for gravitational wave events; and observations of a binary neutron star coalescence with gravitational waves but also with electromagnetic waves and neutrinos by the advanced Laser Interferometer Gravitational wave Observatory (aLIGO) in the United States of America.
- Published
- 2021
- Full Text
- View/download PDF
47. Long Term Periodicity Analysis of OJ 287 at Optical V Waveband.
- Author
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Tang, Jie, Zhang, Hao-Jing, and Pang, Qiao
- Subjects
BL Lacertae objects ,ACQUISITION of data ,RADIO astronomy ,ASTRONOMICAL observatories ,DATABASES - Abstract
BL Lacertae object OJ 287 is one of the blazar that shows convincing evidence to support periodic variations. We have collected V band data for OJ 287 from 1891 to 2010, from the University of Michigan Radio Observatory (UMRAO) database and the available literature. Based on the spectral estimate theory, this paper used the periodogram spectral estimate, the maximum entropy spectral estimate and bispectrum spectral estimate methods. Applying these methods to the periodic analysis of OJ 287, we find the most eminent period as 12.1 yr. The results confirm that the variability period of OJ 287 in the optical V band is in agreement with the radio variability period of about 12 years. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
48. Overview of Atmospheric Simulation Efforts in CTA.
- Author
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Vrastil, Michal
- Subjects
TELESCOPES ,ASTRONOMICAL observatories ,ASTRONOMY ,PHOTONS ,GAMMA rays ,ATMOSPHERIC density - Abstract
Copyright of EPJ Web of Conferences is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2017
- Full Text
- View/download PDF
49. Recent results in γ-ray astronomy with the ARGO-YBJ detector.
- Author
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Di Girolamo, Tristano
- Subjects
COSMIC rays ,COSMIC ray showers ,ASTRONOMICAL observatories ,ASTRONOMY ,PARTICLE detectors - Abstract
The ARGO-YBJ air shower detector has been in stable data taking for five years at the YangBaJing Cosmic Ray Laboratory (Tibet, P.R. China, 4300m a.s.l.) with a duty cycle > 86% and an energy threshold of a few hundreds of GeV. With the scaler mode technique, the minimum threshold of 1 GeV can be reached. In this paper recent results in γ-ray astronomy will be presented, including those from 4.5 years of observations of the blazar Mrk 421 in common with the Fermi satellite. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
50. Editorial.
- Author
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Marks, Robert
- Subjects
ASTRONOMICAL observatories ,AUSTRALIA Day - Published
- 2018
- Full Text
- View/download PDF
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