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One of the key concepts in modern science is force (F). In present studies on the history of dynamics, Patricius is either completely omitted or only cursorily mentioned. The aim of this text is to show that Patricius's concept of the soul, as he developed it in his Nova de universis philosophia from 1591, comes close to the modern (i.e. Newtonian) understanding of force. This should support the more general position that one of the most intriguing aspects of Patricius's philosophy is his contribution to the emergence of modern science. [ABSTRACT FROM AUTHOR]

Kepler published Mysterium Cosmographicum in 1597 constructing his cosmological model based on the five regular polyhedra. Such a creative but weird idea was almost consistent with empirical evidence. Furthermore, following the Pythagorean belief about the connection between music and astronomy, Kepler delved into looking for what things having to do with the planetary movements have the harmonic consonances. This article claims that Kepler's model is a 3M (mathematical, musical, and metaphysical) model and demonstrates how it had been constructed. Furthermore, I explore the reasons behind Kepler's departure from the 3M model and his subsequent consideration of a non-circular orbit, ultimately presenting the Three Laws of Planetary Motion as a consequential outcome. [ABSTRACT FROM AUTHOR]

Planets orbiting binary stars—circumbinary planets—play a paramount role in our understanding of planetary and stellar formation and evolution, dynamical interactions in many-body systems, and the potential for habitable environments beyond the Solar System. Each new discovery holds immense value and inherent fascination both for the astronomical community and for the general public. This is perhaps best demonstrated by the 1500+ citations of the discovery papers for the 14 known transiting circumbinary planets and the dozens of related press-releases in major news outlets. This article reviews the observational and theoretical aspects related to the detection and confirmation of transiting circumbinary planets around main-sequence binaries from space-based surveys, discusses the associated challenges, and highlights some of the recent results. [ABSTRACT FROM AUTHOR]

Kepler's discoveries were permitted by his remarkable insight to place the Sun at the focus of an elliptical planetary orbit. This coordinate system reduces a 2-dimensional orbit to a single spatial dimension. We consider an alternative coordinate system centered on the "image focus," which is the symmetrical (mirror) counterpart of the "real focus" occupied by the Sun. Our analytical approach provides new purely geometric formulae and an exact relationship for the dynamic property of orbital time. In addition, considering the mirror symmetry of the ellipse leads to a simple approximation: the radial hand of an orbital clock rotates counterclockwise at a nearly steady angular velocity 2π/T about the "image focus," where T is the orbital period. This approximation is a useful pedagogic tool and has good accuracy for orbits with low to moderate eccentricities, since the deviation from the exact result goes as eccentricity squared. Planetary comparisons are made. In particular, the angular speeds of Mercury and Jupiter are highly variable in the geocentric and heliocentric reference frames, but are nearly constant in the image focus reference frame. Our findings resolve whether the image focus is the location for observing uniform motion of an elliptical orbit, and pertain to their stability. [ABSTRACT FROM AUTHOR]

According to selective, retentive, scientific realism, past empirical success may be explained only by the parts of past theories that are responsible of their successful predictions being approximately true, and thus theoretically retained, or approximated, by the parts of posterior theories responsible of the same successful predictions. In this article, we present as case study the transit from Ptolemy's to Kepler's astronomy, and their successful predictions for Mars' orbit. We present an account of Ptolemy's successful prediction of Mars' orbit from Kepler's perspective, and scrutinize whether the theoretical elements responsible for Ptolemy's empirical success are approximately retained in Kepler. In order to give to the realist the best chances, we try different strategies. We conclude that all fail and thereby this case constitutes a prima facie strong anomaly for selective retentive realism. Structural realists may call preservation of structure to the rescue, but the existing notions of structure do not work. In absence of a new notion that works, the burden of the proof lies on the realist side. [ABSTRACT FROM AUTHOR]

Optical Intersatellite Links (OISLs) are being considered for future Global Navigation Satellite System (GNSS) constellations. Thanks to OISLs, the constellation incorporates improved clock synchronization and precise ranging among the satellites, which are essential features to achieve accurate time and orbit determination. High data rate communications within the space segment also reduce ground segment dependency, by means of decentralized access to information. However, the dual optimization of data and navigation performance metrics requires a careful assignment of OISLs to the available laser communication terminals on-board. To this end, we present a contact plan design scheme based on a degree constrained minimum spanning tree heuristic applied to such OISL-enabled GNSS (O-GNSS) constellations. Results on the Kepler system, a novel GNSS proposal, show that a fair distribution of connectivity among the constellation can be ensured while optimizing its range-based position estimation capabilities (PDOP). A PDOP improvement of 85 % is reached on average by the optimized contact plan with respect to a generic scheduler that disregards the geometrical distribution of the chosen links. [ABSTRACT FROM AUTHOR]

In two early unpublished texts (a Disputation in favor of Copernicus of 1593 and the Apologia pro Tychone against Ursus of 1600), Kepler argued with the Pythagoreans that, contrary to Aristotle (De caelo, ii, 13), the geometrical center of the cosmos coincides with its natural center. Since the Sun is the body that occupies this central position, Kepler conceives it as the heart of the world and the principle of planetary motion. In the following study, we examine how Kepler further develops this pivotal theme in a letter to Herwart von Hohenburg of 25 March 1605 and later in the Dissertatio cum nuncio sidereo (Prague, 1610) as well as in a German translation and critical commentary of the Aristotelian chapter, which ultimately remained unpublished as well. [ABSTRACT FROM AUTHOR]

This article aims to present a study of some geometrical and physical aspects in the first part of the work Astronomia Nova of 1609, in order to provide subsidies to teachers who want to address the history of astronomy in their basic or higher education subjects. With this focus, we will see how Kepler understood some equivalences between the world systems under discussion in his time and present a study of one of the experiments that Kepler proposed and analyzed geometrically. In this, we noticed a small miscalculation that was not explored in the researched literature, and more than that, it allowed us to understand about the use of geometric constructions in his time and the idea of equivalence that Kepler has in mind. [ABSTRACT FROM AUTHOR]

The paper presents results of precise orbit and Earth parameter determination based on full-scale simulations of a potential future GNSS, with the name of Kepler, recently proposed by the German Aerospace Center. The space segment of the system consists of 24 Galileo-like Medium Earth Orbit (MEO) satellites and 6 Low Earth Orbit (LEO) satellites equipped with ultra-stable optical clocks. All spacecraft carry terminals for two-way optical inter-satellite links (ISLs) enabling high-rate data communication, constellation-wide clock synchronization and precise absolute ranging. The clock synchronization is assumed to create an extremely stable reference time scale based on ensemble of the optical clocks. A series of simulation scenarios are defined, starting from the Galileo constellation as benchmark, and gradually incorporating additional features including LEOs, ISLs and synchronized clocks to assess the impact on orbits, singnal-in-space range errors (SiSREs) and a geodetic quality Earth parameters like polar coordinates, length of day (LOD) and geocenter coordinates. Precise orbit determination (POD) is done at the observation level using the same standards and setups as in real data processing with ground network containing up to 18 stations. The MEO SiSRE, the most relevant to navigation applications, obtained for the Kepler constellation with perfect models and 18 ground stations was found to be 0.009 cm, 160 times better than 1.4 cm found for Galileo. It was demonstrated, that for operational POD for the Kepler system the ground network can be significantly reduced to only two stations if Earth rotation parameters are to be estimated, or to just one otherwise. A SiSRE value of 0.037 cm was obtained with two stations, and 0.018 cm with one station. For more realistic results a number of modeling errors are being considered. These concern observations – multipath, GNSS code hardware delays and ISL range biases, the dynamics – solar radiation pressure (SRP), gravity field, air drag, MEO antenna thrust, Earth tide potential, and the geometry – ocean loading and phase center offsets (PCOs) of space GNSS antennas. Any other satellite and station equipment contribution to mismodeling has been disregarded. It is shown, that for the Kepler the modeling errors are clearly visible in ISL observation residuals, in contrast to Galileo case, where they are to a large extent absorbed by the large number of estimated clock parameters. This was exploited to efficiently mitigate the dynamic modeling errors by estimation of empirical accelerations. With this setup the MEO SiSRE of 5 cm was obtained for Galileo and 0.3 cm, 0.4 cm and 0.7 cm for Kepler with 18, two and one ground station, respectively. The key to obtaining such low values are ISLs and synchronized satellite clocks. In the Kepler constellation with a single ground station the ISL range biases (RBs) up to 5 mm and 20 mm increase the SiSRE to 0.74 cm and 1.67 cm. Estimation of the ISL RBs is not recommended in the presence of modeling errors since they are significantly biased, which leads to increase of SiSRE to 2.2 cm. The Earth parameter determination, based on global network of 124 observing IGS stations, also benefits significantly from the Kepler constellation. The initial results show that the impact of modeling errors on Earth parameters can, as with POD, be effectively reduced in the Kepler system. The 30 cm error in integrated LOD, which has an impact on UT1-UTC, obtained for Galileo due to combined modeling errors could be reduced to 0.5 cm for the Kepler system. The same is true for the Z-coordinate of the geocenter, whose 14 mm error in the MEO-only solution could be reduced to 0.2 mm in the Kepler solution. The Earth parameters completely free of bias are obtained when the number of the modeling errors is reduced to only two: MEO SRP and PCOs. The ISL range biases up to 5 mm were found to have negligible impact on the estimated EPs. The largest differences (up to 0.2 mm) are found for UT1-UTC, for all other parameters they do not exceed 0.02 mm. The estimation of PCOs, being an integral part of Earth parameter determination, also benefits enormously from the Kepler design. It was demonstrated, that using only ten days of data they could be estimated with millimeter accuracy for MEOs and sub-millimeter accuracy for LEOs in all three spacial directions even in the presence of ISL range biases of up to 5 mm. Such accuracy of PCOs is not achievable with the Galileo constellation. [ABSTRACT FROM AUTHOR]

The article explores Johannes Kepler's abortive attempts to produce an opulent, decorative art object to accompany the publication of his first treatise, Mysterium Cosmographicum (1596). It was Kepler's hope that this Credentzbecher, so-called because it was designed to resemble a large, ceremonial chalice, would valorize the significance of what he believed to be an epoch-defining discovery concerning the proportional nature of the planetary intervals and serve as a personal introduction to his local sovereign, Duke Friedrich I of Württemberg (1557–1608). The correspondences of Kepler and his circle, some of which have been reproduced and translated here for the first time, reveal in excruciating detail the struggles to negotiate the demands, and exacting standards, of the Stuttgart court and Kepler's difficulty working with the local goldsmiths employed by the court to enact his vision. Though met with skepticism and destined for failure, the model, its design, and the misunderstandings its failure revealed, poignantly display the sometimes-insurmountable gap between artisanal knowledge and scientific ambition. [ABSTRACT FROM AUTHOR]

The State Archives of Belgium, in particular, the archives of Archduke Albert VII of Austria, hold a letter which possibly is a copy of the letter, or an excerpt of the letter, of Kepler to Emperor Rudolf II of October 1604 on SN1604, that is, the first letter of Kepler on the subject. Together with this letter, there are other letters on SN1604, written by Johannes Brengger and Michiel Coignet. In one of these letters, the very observation by Brengger which Kepler cites can be found. The letters are in Albert's archive because he asked his Court Mathematician Coignet about the phenomenon. It is less clear why Albert was interested in the phenomenon, given the lack of interest in science at his court. [ABSTRACT FROM AUTHOR]

Fake news, misleading claims, hoaxes, half-truths, lies... In order to battle the virus of distrust, fed by fake health news circulating on the internet -- particularly in times of coronavirus -- the solution is to resort to experts such as scientists and professors, activities shared by Hippocrates, Augustine of Hippo and Kepler. From our point of view, the three are amongst those highly regarded sources for becoming well informed of events and uncovering fake news which, as a general rule, is spread by a tweet or a notification which pops up on one's smartphone. In our opinion, the basis of truthful information is not offered by technology as an end in itself. It is the spirit of deep convictions that defines the objectivity underlying the verifiable fact [ABSTRACT FROM AUTHOR]

The application of analytical chemistry to the exploration of the World Cultural Heritage represents a major challenge in that most protocols and strategies are invasive and require micro-sampling. We report a novel methodology for harvesting material deposited on the surface of ancient documents while avoiding their damage or contamination. The technology here described relates to the capture of metals on these specimens. It is based on the use of plastic films (ethylene vinyl acetate, EVA) impregnated with different metal chelators (sodium 2,3-dimercapto-1-propanesulfonate, DMPS, meso-2,3-dimercaptosuccinic acid, DMSA and ethylene diamino tetra acetic acid, EDTA, as calcium salt), for harvesting from surfaces of different supports potential traces of metals therein deposited. The EVA film technology has been used to explore the pages of a manuscript written by Kepler concerning the movements of the moon and catalogued under the title "Hipparchus" at the Archives of the Russian Academy of Sciences (St. Petersburg branch). The EVA-based chelating diskettes were able to capture very significant amounts of different metals, namely: Au, Ag, Hg, As, Pb, suggesting that Kepler, well known as astronomer, astrologist, mathematician and Lutheran theologian, might have started practicing alchemy, a pseudo-chemical science he had learned from his colleague Tycho Brahe in Prague. Image 1 • The EVA film technology for monitoring traces of past life in manuscripts. • An Eva diskette with chelating agents for harvesting metals. • As, Pb, Ag, Au, Hg metal quantitation discovers potential Kepler's work on alchemy. • Four types of EVA films expand our ability of exploring the World Cultural Heritage. [ABSTRACT FROM AUTHOR]

This manuscript reviews recent progress in optical frequency references and optical communication systems and discusses their utilizations in global satellite navigation systems and satellite geodesy. Lasers stabilized with optical cavities or spectroscopy of molecular iodine are analyzed, and a hybrid architecture is proposed to combine both forms of stabilization with the aim of achieving a target frequency stability of 10-15 [s/s] over a wide range of sampling intervals. The synchronization between two optical frequency references in real-time is realized by means of time and frequency transfer on optical carriers. The technologies enabling coherent optical links are reviewed, and the development of an optical communication system for synchronization, ranging and data communication in space is described. An infrastructure exploiting the capabilities of both optical technologies for the realization of a modernized constellation of navigation satellites emitting highly synchronized signals is reviewed. Such infrastructure, named Kepler system, improves satellite navigation in terms intra-system synchronization, orbit determination accuracy, as well as system monitoring and integrity. The potential impact on geodetic key parameters is addressed. [ABSTRACT FROM AUTHOR]

Aristotle held that perception consists in the reception of external sensory qualities (or sensible forms) in the sensorium. This idea is repeated in many forms in contemporary philosophy, including, with regard to vision, in the idea (still not firmly rejected) that the retinal image consists of points of colour. In fact, this is false. Colour is a quality that is constructed by the visual system, and though it is possible to be a realist about colour, it is completely misleading to think of it as received by the retina. Moreover, such supposedly "charitable" interpretations of Aristotle's doctrines, based on misconceptions of perception-science, distort our understanding of his historical context. [ABSTRACT FROM AUTHOR]

• A unique historical approach. • A useful transition technique from Heliocentric to geocentric system and vice versa. • Simulation which could be extended in various celestial objects leading to useful conclusions. • How the free interactive computing tool GeoGebra can be used in astronomical calculations. The word 'Geocentric' comes from the Greek word Γεωκεντρικό which is a compound word composed from two words: "γεω" means Earth and "κεντρικό" means centric. Geocentric aspect, appears for the first time in ancient Greece. Pythagoras had formulated the geocentric system with the Earth at the center of the Universe surrounded by the orbiting planets with Sun included. Later Greek ancient astronomers, trying to explain the weird planetary motion in the sky, introduced the epicyclic theory. 3 3 The epicyclic theory was well formulated by Hipparchus and Apollonius. Using this theory the two famous Greek astronomers managed to explain the weird planetary motion on the sky. This theory states that the geocentric planetary motion could be considered as a combination of circular motions. Today this idea is quite sensible if we consider that the geocentric motion could be perceived as synthesis of two independent motions; one is the rotation of the planet around the Sun and the other is the apparent rotation of the Sun around the Earth. Someone could say that the heliocentric motion is hidden inside the geocentric planetary path as one of two superimposed motions. This logical conclusion is supported by F. Hoyle Hoyle (1975) who states "We know that the difference between a heliocentric theory and a geocentric theory is one of relative motion only, and that such a difference has no physical significance." In other words Geocentrism isn't completely wrong excluding only the arbitrary claim that the Earth is fixed and immobile at the center of the Universe. Geocentrism lasted many years until Nicolaus Copernicus at the middle of 15th century, proposed the heliocentric system by transferring the reference origin from Earth to Sun. Although Copernican model was capable explaining the geocentric orbits of planets with negligible eccentricity, it failed to give a convincing explanation in cases of planets with considerable eccentricity like Mars. The lack of symmetry in Mar's trajectory led Kepler to discover that planet's orbits weren't circular, as it was already believed, but elliptical. According to (Evans, 1998, p.431) Kepler said "I therefore once again think it to have happened by divine arrangement, that I arrived at the same time in which he was intent upon Mars, whose motions provide the only possible access to the hidden secrets of astronomy, without which we would remain forever ignorant of those secrets." In this article we are trying to simulate the process followed by Kepler, studying the apparent geocentric Mar's orbit which triggered him to discover elliptical planetary orbits. The relation between heliocentrism and geocentrism is highlighted during this study. Besides, this aspect is mentioned by David R. Topper...But this fact is then sometimes generalized to positing that geocentrism and Heliocentrism are equivalent, that they are the same geometrically or mathematically or even exactly the same; in a phrase, there is an isomorphism between them... Topper (2007) The methodology which was used, in the whole process, relies on mathematical modeling. This approach is based mainly on dynamic position change over time, which the interactive mathematic software GeoGebra can generously provide. The end of this historical approach shows that the heliocentric view was revealed throughout a geocentric model, proving the equivalence of these two different aspects. Finally the theoretical numerical results of this study seem to be in full agreement with the astronomical records of that era with minimal discrepancies. [ABSTRACT FROM AUTHOR]

Johannes Kepler described the Copernican universe as consisting of a central, small, brilliant sun with its planetary system, all surrounded by giant stars. These stars were far larger than, and much dimmer than, the sun - his De Stella Nova shows that every visible star must exceed the size of the Earth's orbit, and the most prominent stars may exceed the size of the entire planetary system. His other writings, including his response to Ingoli, his Dissertatio cum Nuncio Sidereo, and his Epitome Astronomiae Copernicanae, also reflect this Copernican universe. To Kepler, such a universe was an illustration of divine power - and solid evidence against the stars being suns, against the universe of Giordano Bruno. Kepler's starry universe was in fact the Copernican universe supported by observations of the stars, which showed them to have measurable apparent sizes. Not until the later seventeenth century were those apparent sizes shown to be spurious, allowing for a universe in which the stars were suns. [ABSTRACT FROM AUTHOR]

We revisit the discovery and implications of the first candidate systems to contain multiple transiting exoplanets. These systems were discovered using data from the Kepler space telescope. The initial paper, presenting five systems (Steffen et al., 2010a), was posted online at the time the project released the first catalog of Kepler planet candidates. The first extensive analysis of the observed population of multis was presented in a follow-up paper published the following year (Lissauer et al., 2011b). Multiply-transiting systems allow us to answer a variety of important questions related to the formation and dynamical evolution of planetary systems. These two papers addressed a wide array of topics including: the distribution of orbital period ratios, planet size ratios, system architectures, mean-motion resonance, orbital eccentricities, planet validation and confirmation, and the identification of different planet populations. They set the stage for many subsequent, detailed studies by other groups. Intensive studies of individual multiplanet systems provided some of Kepler 's most important exoplanet discoveries. As we examine the scientific impact of the first of these systems, we also present some history of the people and circumstances surrounding their discoveries. [ABSTRACT FROM AUTHOR]

We describe the circumstances that led to the discovery of Kepler-36b, and the subsequent characterization of its host planetary system. The Kepler-36 system is remarkable for its physical properties: the close separation of the planets, the contrasting densities of the planets despite their proximity, and the short chaotic timescale. Its discovery and characterization was also remarkable for the novelty of the detection technique and for the precise characterization due to the large transit-timing variations caused by the close proximity of the planets, as well as the precise stellar parameters due to asteroseismology. This was the first multi-planet system whose transit data was processed using a fully consistent photometric-dynamical model, using population Markov Chain Monte Carlo techniques to precisely constrain system parameters. Amongst those parameters, the stellar density was found to be consistent with a complementary, concurrent asteroseismic analysis. In a first, the 3D orientation of the planets was constrained from the lack of transit-duration variations. The system yielded insights into the composition and evolution of short-period planet systems. The denser planet appears to have an Earth-like composition, with uncertainties comparable to the highest precision rocky exoplanet measurements, and the planet densities foreshadowed the rocky/gaseous boundary. The formation of this system remains a mystery, but should yield insights into the migration and evolution of compact exoplanet systems. [ABSTRACT FROM AUTHOR]

The Kepler spacecraft's imaging photometer monitored the Pluto system from October–December 2015 during Campaign 7 of the K2 extended mission. Kepler obtained an unprecedented and fortuitous nearly continuous 12-Pluto day lightcurve from measurements acquired every 30 min using long cadence sampling. This 3-month-long baseline anchors the Pluto+Charon lightcurve near the time of the New Horizons July 2015 encounter, observing at solar phase angles between 1.16° and 1.74°. Long-term modeling of Pluto's lightcurve will ultimately reveal its long-term seasonal variation. K2’s combined Pluto+Charon lightcurves measured at this epoch have an average total amplitude of 0.120 ± 0.006, 0.07 magnitudes smaller than the amplitude predicted by a static frost model (Buie and Tholen, 1989) projected from Hubble Space Telescope surface maps (Buie et al., 1992). Subtracting a static Charon lightcurve from the Pluto+Charon K2 lightcurve produces the same results. Likewise, we subtract each rotation model from the model for the first full rotation and find that the average difference of all variations is 0.017 ± 0.008 magnitudes. Moreover, the difference between the first and last K2 rotation is 0.005 magnitudes, implying that there are no significant changes in the lightcurve during the 3 months of K2 observations. These results are consistent with seasonal transport on Pluto's surface and the predictions of Buratti et al. (2015a) . However, a detailed understanding of the surface-atmosphere interactions associated with these phenomena requires decades of monitoring. [ABSTRACT FROM AUTHOR]

In the history of warfare various media and technologies have been devised both to enable contingent events in the form of scenarios and simulations and to reign them in and bring the proliferation of possible futures under control. War games, horoscopes, astrolabes, celestial and topographical maps have in different ways served as 'contingency media', i.e. tools that enable strategic thought and action under conditions of uncertainty. Through the prism of Schiller's Wallenstein from 1799, this essay examines the development of military contingency media from the 17th to the early 19th century. Delving into the disagreements between Johannes Kepler and the historical Wallenstein about the reach and power of astrological star charts and horoscopes, the essay analyzes Schiller's late Enlightenment critique of astrological contingency media as well as his transformation of them into productive poetic devices. Finally, it situates the play in the context of military theory around 1800 in which contingency emerged as a central factor of large-scale warfare. A historically complex document, Wallenstein serves as an archive of the shifting conceptions of war and of the media devised to manage its uncertain futures. [ABSTRACT FROM AUTHOR]

The fields of astronomy and astrophysics are currently engaged in an unprecedented era of discovery as recent missions have revealed thousands of exoplanets orbiting other stars. While the Kepler Space Telescope mission has enabled most of these exoplanets to be detected by identifying transiting events, exoplanets often exhibit additional photometric effects that can be used to improve the characterization of exoplanets. The EXONEST Exoplanetary Explorer is a Bayesian exoplanet inference engine based on nested sampling and originally designed to analyze archived Kepler Space Telescope and CoRoT (Convection Rotation et Transits planétaires) exoplanet mission data. We discuss the EXONEST software package and describe how it accommodates plug-and-play models of exoplanet-associated photometric effects for the purpose of exoplanet detection, characterization and scientific hypothesis testing. The current suite of models allows for both circular and eccentric orbits in conjunction with photometric effects, such as the primary transit and secondary eclipse, reflected light, thermal emissions, ellipsoidal variations, Doppler beaming and superrotation. We discuss our new efforts to expand the capabilities of the software to include more subtle photometric effects involving reflected and refracted light. We discuss the EXONEST inference engine design and introduce our plans to port the current MATLAB-based EXONEST software package over to the next generation Exoplanetary Explorer, which will be a Python-based open source project with the capability to employ third-party plug-and-play models of exoplanet-related photometric effects. [ABSTRACT FROM AUTHOR]

The article addresses the genesis and visualization of the capstone image to Kepler’s polyhedral hypothesis of the planetary intervals from his first major work, Mysterium Cosmographicum (1596). The contention is that the famous Tabula III was directed less by Kepler than it was an initiative spearheaded by Georg Gruppenbach, the printer of Mysterium, and Kepler’s mentor Michael Mäistlin, who sought to produce a marketable broadsheet that would appeal to the contemporary German fashion for illustrations of polyhedral geometry. More generally, the article seeks to redefine the key role played by the printing workshop and the decorative arts in the theory’s inception and ultimate graphic manifestation. [ABSTRACT FROM AUTHOR]

We analyze data from the Quarter 1-17 Data Release 24 (Q1-Q17 DR24) planet candidate catalog from NASA's Kepler mission, specifically comparing systems with single transiting planets to systems with multiple transiting planets, and identify a population of exoplanets with a necessarily distinct system architecture. Such an architecture likely indicates a different branch in their evolutionary past relative to the typical Kepler system. The key feature of these planetary systems is an isolated, Earth-sized planet with a roughly 1-d orbital period. We estimate that at least 24 of the 144 systems we examined (≳17%) are members of this population. Accounting for detection efficiency, such planetary systems occur with a frequency similar to the hot Jupiters. [ABSTRACT FROM AUTHOR]

Finding the shortest paths from a single source to all other vertices is a common problem in graph analysis. The Bellman-Ford's algorithm is the solution that solves such a single-source shortest path (SSSP) problem and better applies to be parallelized for many-core architectures. Nevertheless, the high degree of parallelism is guaranteed at the cost of low work efficiency, which, compared to similar algorithms in literature (e.g., Dijkstra's) involves much more redundant work and a consequent waste of power consumption. This article presents a parallel implementation of the Bellman-Ford algorithm that exploits the architectural characteristics of recent GPU architectures (i.e., NVIDIA Kepler, Maxwell) to improve both performance and work efficiency. The article presents different optimizations to the implementation, which are oriented both to the algorithm and to the architecture. The experimental results show that the proposed implementation provides an average speedup of 5× higher than the existing most efficient parallel implementations for SSSP, that it works on graphs where those implementations cannot work or are inefficient (e.g., graphs with negative weight edges, sparse graphs), and that it sensibly reduces the redundant work caused by the parallelization process. [ABSTRACT FROM AUTHOR]

In this paper, a task-scheduling approach to efficiently calculating sparse symmetric matrix-vector products and designed to run on graphics processing units (GPUs) is presented. The main premise is that, for many sparse symmetric matrices occurring in common applications, it is possible to obtain significant reductions in memory usage and improvements in performance when the matrix is prepared in certain ways prior to computation. The preprocessing proposed in this paper employs task scheduling to overcome the difficulties that have suppressed the development of methods taking advantage of the symmetry of sparse matrices. The performance of the proposed task-scheduling method is verified using a Kepler (Tesla K40c) graphics accelerator, and is compared to the performance of cuSPARSE library functions on a GPU and to functions from the Intel MKL on central processing units (CPUs) executed in the parallel mode. The obtained results indicate that the proposed approach for sparse symmetric matrix-vector products results in up to a 40% reduction in memory usage, as compared to nonsymmetric matrix storage formats, while retaining good throughput. Compared to cuSPARSE and Intel MKL functions for sparse symmetric matrices, the proposed TSMV approach allowed us to achieve a significant speedup (of over one order of magnitude). [ABSTRACT FROM AUTHOR]

In Astronomia nova (1609), Kepler quantified a geometrically exact measure of time. His innovative approach was to consider intervals (discrete but) so small that in his terms the results became exact. He divided the orbit (initially circular) into 360 equal arcs from its centre to establish uniformity of time, and combined these arcs with 360 distances drawn from the Sun, to represent variable increments of time in orbit. Those increments did not accurately measure areas; but subsequently Kepler discovered a sound geometrical reformulation of the increment which produced an area-representation that he was able straightforwardly to sum. (He wrongly described his method as ‘distance-summation’). Then the time in orbit was measured by a sector of the exact ellipse he had concurrently constructed, founded on the work of Archimedes. Essential diagrams, and the notable justification, from Euclid’s Elements, of the reformulation of the increment, have been added on Kepler’s behalf. [ABSTRACT FROM AUTHOR]

During the 16th century, a skeptical approach on the status of astronomical hypothesis was widely spread among Lutheran communities and particularly among the astronomers belonging to those communities. Astronomical hypotheses were conceived as mere devices to save appearances (calculation tools), much more than entities to describe the real structure of the universe. Towards the end of century, Johannes Kepler hardly attacks this kind of skepticism. In his Apologia pro Tychone contra Ursum, the young Kepler introduces a set of fresh ideas concerning the nature of astronomical hypothesis as part of a strategy deployed against skepticism. I suggest that a new theory of hypothesis underlies Kepler's strategy. [ABSTRACT FROM AUTHOR]

In this work we give a general overview on Johannes Kepler's astronomical work. We treat, in a chronological order, the four most important books related to the issue written by him, namely, the Mysterium Cosmographicum, the Astronomia Nova, The Harmony of the Worlds and Epitome of Copernican Astronomy, in order to make clear the historical stages of the development of the author's scientific thought. We tried to emphasize the rather determining presence in his thought of a philosophical-theological element and a physical conception, as well as a methodological inclination already typical of the emerging modern science. [ABSTRACT FROM AUTHOR]

This paper examines the underdetermination between the Ptolemaic, Copernican, and the Tychonic theories of planetary motions and its attempted resolution by Kepler. I argue that past philosophical analyses of the problem of the planetary motions have not adequately grasped a method through which the underdetermination might have been resolved. This method involves a procedure of what I characterize as decomposition and identification. I show that this procedure is used by Kepler in the first half of the Astronomia Nova , where he ultimately claims to have refuted the Ptolemaic theory, thus partially overcoming the underdetermination. Finally, I compare this method with other views of scientific inference such as bootstrapping. [ABSTRACT FROM AUTHOR]

Background: Mandatory deposit of raw microarray data files for public access, prior to study publication, provides significant opportunities to conduct new bioinformatics analyses within and across multiple datasets. Analysis of raw microarray data files (e.g. Affymetrix CEL files) can be time consuming, complex, and requires fundamental computational and bioinformatics skills. The development of analytical workflows to automate these tasks simplifies the processing of, improves the efficiency of, and serves to standardize multiple and sequential analyses. Once installed, workflows facilitate the tedious steps required to run rapid intra- and inter-dataset comparisons. Results: We developed a workflow to facilitate and standardize Meta-Analysis of Affymetrix Microarray Data analysis (MAAMD) in Kepler. Two freely available stand-alone software tools, R and AltAnalyze were embedded in MAAMD. The inputs of MAAMD are user-editable csv files, which contain sample information and parameters describing the locations of input files and required tools. MAAMD was tested by analyzing 4 different GEO datasets from mice and drosophila. MAAMD automates data downloading, data organization, data quality control assesment, differential gene expression analysis, clustering analysis, pathway visualization, gene-set enrichment analysis, and cross-species orthologous-gene comparisons. MAAMD was utilized to identify gene orthologues responding to hypoxia or hyperoxia in both mice and drosophila. The entire set of analyses for 4 datasets (34 total microarrays) finished in ~ one hour. Conclusions: MAAMD saves time, minimizes the required computer skills, and offers a standardized procedure for users to analyze microarray datasets and make new intra- and inter-dataset comparisons. [ABSTRACT FROM AUTHOR]

This article deals with reservations several Church Fathers had to astronomy and the consequences that this had for early modem astronomy. In general, the Church Fathers criticised astronomy as vain curiosity that does Christians no good. I argue that when the early modem astronomers stressed the usefulness of their discipline, it was not an expression of a new utifitarian way of thinking, but an attempt to neutralise these theological objections by highlighting the religious, social and moral benefits of astronomy. The spirit of material utility for which modem science was reproached in the twentieth century originally emerged as a need to legitimise science against the objections of theology. [ABSTRACT FROM AUTHOR]

The choice of thread-block size and shape is one of the most important user decisions when a parallel problem is written for any CUDA architecture. The reason is that thread-block geometry has a significant impact on the global performance of the program. Unfortunately, the programmer has not enough information about the subtle interactions between this choice of parameters and the underlying hardware. This paper presents uBench, a complete suite of micro-benchmarks, in order to explore the impact on performance of (1) the thread-block geometry choice criteria, and (2) the GPU hardware resources and configurations. Each micro-benchmark has been designed to be as simple as possible to focus on a single effect derived from the hardware and thread-block parameter choice. As an example of the capabilities of this benchmark suite, this paper shows an experimental evaluation and comparison of Fermi and Kepler architectures. Our study reveals that, in spite of the new hardware details introduced by Kepler, the principles underlying the block geometry selection criteria are similar for both architectures. [ABSTRACT FROM AUTHOR]

The Kepler scientific workflow system enables creation, execution and sharing of workflows across a broad range of scientific and engineering disciplines while also facilitating remote and distributed execution of workflows. In this paper, we present and compare different approaches to distributed execution of workflows using the Kepler environment, including a distributed data-parallel framework using Hadoop and Stratosphere, and Cloud and Grid execution using Serpens, Nimrod/K and Globus actors. We also present real-life applications in computational chemistry, bioinformatics and computational physics to demonstrate the usage of different distributed computing capabilities of Kepler in executable workflows. We further analyze the differences of each approach and provide a guidance for their applications. [ABSTRACT FROM AUTHOR]

• The development and advantages of microlens array scanners are reviewed. • Mathematical model of different structure microlens array scanner is established. • The performance of different structure microlens array scanners are compared. • This paper is helpful to the design of an optical system with beam deflectors. Large aperture, compact, lightweight beam scanning systems operating in the infrared atmospheric window are attractive for aerial-based applications such as long-range lidar and countermeasures. The multiple micro lens arrays based micro lens array scanner (MLAS) with compact structure and low weight, which can be seemed as a quasi-optical phased array, is capable of large-aperture infrared beam scanning. The incident laser beam with a large aperture is separated into an array of multiple sub-beams by the MLAS, and the tip/tilt phases of the exiting sub-beams are controlled simultaneously by a relative translation (in micrometer level) of the micro lens arrays without a complex and large control circuit. In this paper, complete mathematical models have been established to describe the characteristics of MLAS with Kepler structure, Galileo structure and Modified-Kepler structure respectively. The performance of three type of MLAS, such as the maximum scanning angle and the main spot energy, etc., are theoretically analyzed and compared. The comparison presented in this paper is expected to be helpful to the designs of infrared optical systems with light beam deflectors and to provide guidelines for practical developments of MLAS. [ABSTRACT FROM AUTHOR]

We perform a survey of the Cr, Mn, and Fe-K emission lines in young supernova remnants (SNRs)with the Japanese X-ray astronomy satellite Suzaku. The Cr and/or Mn emission lines are detected in 3C 397 and 0519-69.0 for the first time. We also confirm the detection of these lines in Kepler, W49B, N103B, and Cas A. We derive the line parameters (i.e., the line centroid energy, flux, and equivalent width (EW)) for these six sources and perform a correlation analysis for the line center energies of Cr, Mn, and Fe. Also included in the correlation analysis are Tycho and G344.7-0.1 for which the Cr, Mn, and Fe-K line parameters were available in the literature through Suzaku observations. We find that the line center energies of Cr correlate very well with that of Fe and that of Mn. This confirms our previous findings that Cr, Mn, and Fe are spatially co-located, share a similar ionization state, and have a common origin in the supernova nucleosynthesis. We find that the ratio of the EW of the Cr emission line to that of Fe (γCr/Fe ≡ EW(Cr)/EW(Fe)) provides useful constraints on the SNR progenitors and on the SN explosion mechanisms: for SNRs with γCr/Fe > 2%, a Type Ia origin is favored (e.g., N103B, G344.7-0.1, 3C 397, and 0519-69.0); for SNRs with γCr/Fe < 2%, they could be of either core-collapse origin or carbon-deflagration Ia origin. [ABSTRACT FROM AUTHOR]

Abstract: The feedback control of fusion experiments in tokamak devices is entering a new area driven by the increase of control requirements for obtaining burning plasmas under safe operation conditions. A project aiming at setting up a flight simulator for the development of advanced controllers has recently started at CEA. This simulator reuses most of the components of the European integrated tokamak modelling (ITM) simulation platform. Thus, it benefits from the development made by the task force and it will be able to offer a development platform for the new controllers of present day European tokamaks and future machines. The paper will report on the different software developments performed in order to set up a flexible and user friendly design and test of feedback control loops. [Copyright &y& Elsevier]

The application of scientific workflow systems for orchestrating complex tasks is still an open research area. In particular, earth system related modeling applications consists of different tasks that are closely related to each other and scientific workflow systems can be used to simplify these sub processes and their relationships. The motivation for this work is driven by the complexities of running a large modeling system on a high performance computing and network systems and need to reduce those complexities, particularly for the average user. In this study, it is presented and analyzed a new methodology to combine scientific workflow system and modeling framework approach together to create standardized work environment. Then, the pro-posed methodology is tested using a typical and realistic earth system modeling application. The result of example workflows that are based on the pro-posed methodology is a part of this study. A Modeling framework is a standardized programming environment for combining model components and couplers of different kinds of earth system models using a common calling interface. Earth System Modeling Framework (ESMF) is one of the most popular examples for this approach. It consists of a superstructure for coupling components of Earth system applications and an infrastructure of robust, high-performance utilities and data structures that ensures consistent component behavior. Extending beyond the modeling framework approach, scientific workflow systems create standardized interfaces to a variety of technologies and automate the execution and monitoring of a heterogeneous workflow. Namely, a scientific workflow system is a problem-solving environment that simplifies tasks by creating meaningful and easy understandable sub-tasks and combining them to form executable data management and analysis pipelines. Kepler was chosen as the workflow environment for this work because it is open source, platform independent, and it supports different models of computation such as Process Network (PN) and Synchronous Data Flow (SDF). Kepler is a scientific work-flow system that is based on the Ptolemy II project. The actor-oriented design of Kepler enables users to create hierarchically structured scientific workflows. The overall execution of model is controlled by separate component that is called a director (a special actor). Kepler supports different model of computation types via its directors. In application example, a regional coupled climate modeling system is developed for Mediterranean region and integrated into workflow system to provide better representation of regional climate system. This application has crucial importance in downscaling output of the global circulation models over Turkey and near regions. It also can be used to create better representation of regional climate for the future scenarios. The workflow application also collects provenance information automatically from the coupled earth system modeling system to reproduce, compare and debug results. The coupled atmosphere-ocean modeling system is based on NCAR's Weather Research and Forecasting (WRF) and Regional Ocean Modeling System (ROMS) model. To couple atmosphere and ocean models the ESMF library is used. For the atmospheric component (WRF), the experimental ESMF-IO structure is used to create ESMF fields and states to share data between different model components. The WRF ESMF-IO is also modified to add field level metadata into coupling variables (heat and momentum fluxes) of atmospheric model. In ocean component (ROMS), the coupler code is written to control each model component and also the gridded component code is developed to run each earth system model via ESMF init, run and finalize methods. The gridded component level metadata is added into coupler to create prototype version of self-describing modeling system. The results show that the developed workflow environment is capable of running different earth system models on a different high performance computing resource with a meaningful abstraction. The pro-posed work environment acts as an abstraction layer and hides the detail of the used infrastructure and earth system model from user and it also collect standardized provenance information about both model and computing resource to represent the work environment as possible as it can. [ABSTRACT FROM AUTHOR]

The theological framework for Kepler's cosmos is based on a metaphorical Trinitarian symbolism, with the sun as God the Father, the firmament as Jesus Christ, and the intervening space as the Holy Spirit. In his heliocentric cosmology the sun becomes the source of planetary movement just as in the Aristotelian geocentric universe God's love beyond the starry realm was seen as the source of the eternal motion of the spheres. Searching for a divinely rooted physical explanation of planetary orbital motion, Kepler began with his solar-oriented distance law, which miraculously led to his law of areas. Finally he chose the ellipse from competing curves because its focus ('hearth') coincided with the sun, the source of God-given motion. [ABSTRACT FROM AUTHOR]

Abstract: The feedback control of fusion experiments in tokamak devices is entering a new area driven by the increase of control requirements for obtaining burning plasmas under safe operation conditions. A project aiming at setting up a flight simulator for the development of advanced controllers has started last year at CEA. This simulator will reuse most of the components of the European Integrated Tokamak Modelling (ITM) simulation platform. Thus, it will benefit from the development made by the task force and it will be able to offer a development platform for the new controllers of present day European tokamaks and future machines. This paper provides an overview of the architecture of the simulator. The functional specifications of the simulator have been defined and the needs in interface implementation are analysed as well. [ABSTRACT FROM AUTHOR]

Mereology is the philosophical study of part/whole relations. Copernicus, Mästlin, and Kepler addressed explicitly some of the logical issues in their support of heliocentrism. Their emphasis on harmony and commensurability to evaluate theories as more or less likely fits with their use of part/whole relations to argue for the greater reasonability or probability of heliocentrism. The essay summarizes the logical and metaphysical issues that earlier traditions discussed, and it uses those discussions to illuminate features of heliocentric theories that remain otherwise obscure even in Newton. [ABSTRACT FROM AUTHOR]

Abstract: Results of our research on 2D Archemedean lattice photonic crystals are presented. This involves the calculations of the band structures, band-gap maps, equifrequency contours and FDTD simulations of electromagnetic propagation through the structures as well as an experimental verification of negative refraction at microwaves. The band-gap dependence on dielectric contrast is established both for dielectric rods in air and air-holes in dielectric materials. A special emphasis is placed on possibilities of negative refraction and left-handedness in these structures. Together with the familiar Archimedean lattices like square, triangular, honeycomb and Kagome’ ones, we consider also, the less known, (32,4,3,4) (ladybug) and (3,4,6,4) (honeycomb-ring) structures. [Copyright &y& Elsevier]

The question ‘Are supernovae important sources of dust?’ is a contentious one. Observations with the Infrared Astronomical Satellite (IRAS) and the Infrared Space Observatory (ISO) only detected very small amounts of hot dust in supernova remnants. Here, we review observations of two young Galactic remnants with the Submillimetre Common User Bolometer Array (SCUBA), which imply that large quantities of dust are produced by supernovae. The association of dust with the Cassiopeia A remnant is in question owing to the contamination of foreground material. In this paper, we compare the emission from cold dust with CO emission towards Kepler’s supernova remnant. We detect very little CO at the location of the submillimetre peaks. A comparison of masses from the CO and the dust clouds are made, and we estimate the 3σ upper limit on the gas-to-dust ratios to be in the range 20–60. These results suggest that we cannot yet rule out freshly-formed or swept-up circumstellar dust in Kepler’s supernova remnant. [ABSTRACT FROM AUTHOR]

Der Nobelpreis für Physik 2019 geht zur einen Hälfte an James Peebles "für theoretische Entdeckungen in der physikalischen Kosmologie" und zur anderen Hälfte gemeinsam an Michel Mayor und Didier Queloz "für die Entdeckung eines Exoplaneten, der einen sonnenähnlichen Stern umkreist." Der Nobelpreis für Physik 2019 geht zur einen Hälfte an James Peebles "für theoretische Entdeckungen in der physikalischen Kosmologie" und zur anderen Hälfte gemeinsam an Michel Mayor und Didier Queloz "für die Entdeckung eines Exoplaneten, der einen sonnenähnlichen Stern umkreist". Das heutige Standardmodell des Universums beruht auf lediglich drei Annahmen: Es baut auf der Allgemeinen Relativitätstheorie auf und nimmt weiter an, dass uns das Universum im Mittel richtungsunabhängig erscheint und dass dies auch für jeden anderen Beobachter gilt, es also homogen und isotrop ist. Wieder war es Peebles, der aus dieser Krise einen Ausweg fand: Er stellte 1982 fest, dass die Amplitude der Temperaturschwankungen im jungen Universum wesentlich geringer ausfallen könnte, wenn der Großteil der kosmischen Materie gar nicht mit Licht wechselwirken kann, in diesem Sinn also dunkel wäre [3]. [Extracted from the article]

Everyone knows Galileo Galilei as an astronomer, physicist and writer of books that changed our perception of the world. Few people know that Galileo also wrote poetry in elegant XVI century Italian. In 1590, aged 26, Galileo was a lecturer of mathematics at the University of Pisa, the poorest paid of the faculty. He dutifully taught Euclid, but quickly ran into trouble: he despised and openly challenged Pisa's strict academic traditions. Especially the rule by which all professors had to wear their gown at all times, under penalty of a stiff fine. To chastise and mock such rule, he wrote his longest poem, the 301-line Capitolo "Against the Donning of the Gown". [ABSTRACT FROM AUTHOR]

This paper explains how Kepler in his ``War on Mars'' applied systems of models organized both in a perspectival and in a stratified conceptual sense. With the help of these systems Kepler worked out successively more determinate models for the planetary orbits. Along the way he discovered the Keplerian laws as consequences of the distance rule, his leading regulative principle. The selection of decisive, so called privileged, observations, as well as the determinate geometrical and kinematical description of the phenomena, result from the application of this principle to the developing of models. Kepler's method of discovery may therefore appropriately be designated converse abduction. [ABSTRACT FROM AUTHOR]

Radio emission of the historical supernovae remnants Tycho (SNR1572) and Kepler (SNR1604) and evolution of their luminosity are considered. Measurement data of secular luminosity decrease rate, obtained earlier by the authors, were corrected with account of variation in time of the flux density of the reference sources. As a result, it is found that the SNR1604 luminosity at 1667 MHz is weakening with an annual mean rate equal to (0.2 ± 0.07)%. The corresponding rate for SNR1572 is (0.47 ± 0.05)%. Since the radio luminosity evolution, as well as energy densities of magnetic field and relativistic electrons inside SNR1604 and SNR1572 are essentially different, these remnants should be considered as different types of supernovae. Bandiera classified SN1604 as type SNIb or SNII. [ABSTRACT FROM AUTHOR]

In this paper I argue against the traditional view that in discovery processes there is no place for rational decisions. First I argue that some historical processes in which an empirical law was developed, were rational. Second, I identify some of the methodological rules that we can follow in order to be rational when constructing an empirical law. Finally, I argue that people who deny that scientific discovery can be rational do not understand the nature of methodological rules. [ABSTRACT FROM AUTHOR]