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Ann Sci ; 78(4): 401-417, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34402408


This article is devoted to a thirteenth-century Latin text on how to construct, set up, and use a version of the so-called armillary instrument (instrumentum armillarum), which was first described in Ptolemy's Almagest as a tool for measuring ecliptic coordinates. Written in 1264 by Guillaume des Moustiers, bishop of Laon, this hitherto unstudied Tractatus super armillas survives in a single manuscript, where it is accompanied by a copious set of glosses. The text and its glosses jointly offer an unusually detailed account of the instrument's material aspects and methods of assembly. In addition, they reflect a keen awareness of the potential sources of error that may arise in the context of astronomical observation, while making suggestions on how these errors may be minimized or avoided. The Tractatus super armillas accordingly is a valuable source on the observational side of medieval European astronomy, which has often been minimized in modern historical accounts.

Astronomia , Envio de Mensagens de Texto , Europa (Continente) , Processos Mentais
Ann Sci ; 78(4): 418-462, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34308799


Our discussion of Niccolò Tornioli's The Astronomers questions some of the traditional identifications of its characters, although we cannot claim to have solved these figures' identities and several remain a mystery. We do present new iconographic interpretations of particular scientific instruments, diagrams, and natural phenomena in the canvas. These novel readings occasionally remain conjectural in part because Tornioli represents these entities in a way that makes it clear that he did not fully comprehend them. The errors and obscurities in Tornioli's painting lead us to two conclusions. First, that his erudite patron Virgilio Spada was unlikely to have been involved in the definition of the painting's iconographies, as he would have objected to Tornioli's crass mistakes and obscure imagery. Second, that these errors and indistinct details should be taken at face value, insofar as they accentuate the difficulties of astronomical observation. Beyond highlighting these challenges, we argue that the painting also visualizes techniques for countering them. Specifically, the canvas would have focused early modern observers' attention on the edifying powers of civil conversations and communal observations with scientific instruments as well as images-including diagrams, celestial maps, and paintings.

Pinturas , Astronomia
Life Sci Space Res (Amst) ; 30: 29-38, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34281662


The search for life-supporting molecules in outer space is an ever-growing endeavour. Towards this, the computational chemistry supporting the astronomical spectroscopic observations is becoming a valuable tool to unravel the complex chemical network in interstellar medium (ISM). In the present work, quantum-mechanical computations, accounting for anharmonic effects, are performed to obtain the rotational and vibrational line-data for the gas-phase conformers of proteinogenic amino acid Leucine and its isomeric species predicted to be involved in its stereoinversion under the extreme environment of ISM. These species exhibit diverse chemistry including branched skeleton and zwitterionic ammonium ylides. A few of the species have significantly high dipole moment, which can act as tracer for the conformers of Leucine having low dipole moment. Besides this, the species, which are terrestrially less stable, can be of significant importance to the astronomers. Notably, the spectral database generated in this work can assist in the detection of proteinogenic Leucine and its isomeric species in different regions of ISM.

Aminoácidos , Meio Ambiente Extraterreno , Astronomia , Leucina , Análise Espectral
Nature ; 594(7861): 30-31, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34079132
Nature ; 594(7863): 343-344, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34135515
Ann Sci ; 78(3): 295-333, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34182883


This article interprets a recently recovered manuscript, Tratado de astronomía y la reformaçión del tiempo, composed by Antonio Sánchez in New Granada c.1696, in the context of the Spanish and Renaissance cosmographies. Sánchez's Tratado proposes a spherical astronomy, in which celestial bodies - including comets - move in orbs containing pyramidal knots that explain the changing speed observed in the motion of planets. From this astronomy and following the peninsular style of repertorios, Sánchez derives two major conclusions: the corrected length of the solar year and a revised birth date of Jesus. Taking as center of reference Vélez, where Sánchez was based, these claims led to conclusions in domains ranging from calendric astronomy to eschatology, including the incorporation of the indigenous peoples into salvation narrative and a demonstration of the arrangement of the celestial orbs at the Last Judgment. Sánchez's Tratado constitutes an expansion of the Spanish mathematical cosmography that sheds light on the production of knowledge in the Spanish-American world and, at the same time, provides elements to reassess our understanding of the global circulation of Renaissance and early modern ideas.

Astronomia , Planetas , Conhecimento , Matemática
Ann Sci ; 78(3): 265-294, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33969813


In 1588 Tycho Brahe proposed a new cosmological system keeping a motionless Earth at the centre of the world. In the first half of the following century the reception of Tycho's model within the Society of Jesus was characterized by a strong resistance at the beginning, followed by a long and winding path, and then a good fortune, whereas heliocentric models were increasingly investigated in European observatories. In 1651 a Jesuit astronomer, Giovan Battista Riccioli, published the Almagestum novum, an encyclopaedic synthesis of astronomical knowledge where the Earth's motions or rest were extensively discussed in order to prove the Earth's immobility. However, through the period 1650-1687 the Almagestum novum did not entirely fulfil its aims, rather seeming like the dying swan's song of Tychonic or semi-Tychonic models. Contemporary scholars appreciated the encyclopaedic effort by Riccioli, but many were critical of his proofs. Even influential Jesuit astronomers showed a remarkable interest in the Copernican model, accepting geocentric models only on the basis of Holy Scripture's authority. This conduct and the tacitly allowed circulation in Catholic Europe of openly Copernican books, indicate that Catholic science tolerated heliocentric theory, when presented as a computational device rather than a representation of reality, more frequently than we usually think.

Astronomia , Planeta Terra , Catolicismo , Europa (Continente) , Movimento (Física)
An Acad Bras Cienc ; 93(suppl 1): e20201026, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34008768


The Intelligent Observatory (IO) refers to the vision of the South African Astronomical Observatory (SAAO) to meet the scientific needs of both the South African and international astronomical communities by providing a better and more efficient service. The idea behind the IO is to harmonise the astronomical operations of all the hosted and local astronomical facilities on the Sutherland Plateau. The vision requires both upgrades to some of the telescopes and a re-design of the current Sutherland operations model. The primary science driver, for the IO, is time-domain and transient science.

Astronomia , Tempo
Nature ; 593(7857): 40-41, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33953406
An Acad Bras Cienc ; 93(suppl 1): e20200808, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33909811


We present brief highlights and updates on some newer projects, both in operation/construction and in preparation stages, of astronomical research on Mainland China, with an emphasis on those involving international collaborations. Limited by the scope of this paper, this sample is not meant to be uniform nor comprehensive, and in some cases it may not be fully up to date. For more specific and detailed information on these or other projects, we refer the readers to the official websites of these projects and those of the National Astronomical Observatories, Chinese Academy of Sciences.

Astronomia , China
An Acad Bras Cienc ; 93(suppl 1): e20201759, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33909814

Astronomia , China
An Acad Bras Cienc ; 93(suppl 1): e20201624, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33852657

Astronomia , China
Ann Sci ; 78(2): 162-196, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33646924


We are interested in the case of Friedrich Christoph Mayer, who in the 1720s, while at the Imperial Academy of Sciences in St. Petersburg (in Latin Academiae scientiarum imperialis Petropolitanae), developed a system of the aurora borealis, as well as a mathematical method for calculating the height of the aurora from the geometrical characteristics of the auroral arc. Mayer, encountering a major contradiction in his system which placed the aurora at the height of the clouds, whereas his mathematical method led to an altitude a hundred times higher, never applied his method to concrete cases to deduce the height of the aurora, and quickly lost interest in their detailed description, a task that was nevertheless assigned to him at the St. Petersburg Observatory. Jean-Jacques Dortous de Mairan suggests that Mayer's abandonment was due to his lack of confidence in observations. We set Mayer's case against that of Leonhard Euler who, working with Mayer and being aware of the great height of the aurora, later developed a system of the aurora borealis that was compatible with the observational fact. We put forward possible hypotheses to explain Mayer's disinterest in observing the aurora and in the mathematical method he himself had developed.

Astronomia/história , Atmosfera , Meio Ambiente Extraterreno , Alemanha , História do Século XVIII , Modelos Teóricos , Federação Russa
Astrobiology ; 21(6): 757-763, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33739859


I propose a version of the Drake equation to include searching for alien artifacts, which may be located on the Moon, Earth Trojans, and Earth co-orbital objects. The virtue of searching for artifacts is their lingering endurance in space, long after they go dead. I compare a search for extraterrestrial artifacts (SETA) strategy with the existing listening to stars search for extraterrestrial intelligence (SETI) strategy. I construct a ratio of a SETA Drake equation for artifacts to the conventional Drake equation so that most terms cancel out. This ratio is a good way to debate the efficacy of SETI versus SETA. The ratio is the product of two terms: one is the ratio of the length of time that probes from extraterrestrial (ET) civilizations could be present in the near-Earth region to the length of time that ET civilizations transmit signals to the Solar System. The second term is the ratio of the respective origin volumes: the volume from which probes can come, which is affected by the long-term passage of stars near the Sun, to the volume of transmitting civilizations. Scenarios are quantified that suggest that looking for alien artifacts near Earth is a credible alternative approach relative to listening to stars. This argues for emphasis on artifact searches, ET archeology. I suggest study of existing high-resolution images of the Moon, imaging of the Earth Trojans and Earth co-orbitals, and probe missions to the latter two. Close inspection in these near-Earth regions, which also may hold primordial remnants of the early Solar System, yields concrete astronomical research.

Exobiologia , Meio Ambiente Extraterreno , Artefatos , Astronomia , Espécies Introduzidas
Nature ; 591(7849): 206-207, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33692553

Astronomia , Gelo , Física
Elife ; 102021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33734086


Research suggests that scientists based at prestigious institutions receive more credit for their work than scientists based at less prestigious institutions, as do scientists working in certain countries. We examined the extent to which country- and institution-related status signals drive such differences in scientific recognition. In a preregistered survey experiment, we asked 4,147 scientists from six disciplines (astronomy, cardiology, materials science, political science, psychology and public health) to rate abstracts that varied on two factors: (i) author country (high status vs lower status in science); (ii) author institution (high status vs lower status university). We found only weak evidence of country- or institution-related status bias, and mixed regression models with discipline as random-effect parameter indicated that any plausible bias not detected by our study must be small in size.

Indexação e Redação de Resumos , Revisão por Pares/métodos , Viés de Publicação/estatística & dados numéricos , Astronomia , Cardiologia , Geografia , Humanos , Pessoal de Laboratório , Modelos Lineares , Ciência dos Materiais , Psicologia , Saúde Pública , Inquéritos e Questionários , Universidades
Nature ; 590(7845): 226-227, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33568818

Astronomia , Física