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Asteroseismology, the study of intrinsic oscillations in stars, can reveal fundamental properties of cool stars critical in our understanding of stellar rotational evolution. Through space missions such as Kepler and TESS, asteroseismology has seen a surge of new data and research in the past decade. These data have contributed to important results in the field of stellar braking particularly for F, G and K stars, thanks to estimates of stellar age for rotating field stars, and the measurement of stellar rotation through oscillation spectra as important comparisons for estimates from star-spots. In this talk, I will provide an introduction to asteroseismology how it can provide important results for your research. This will be followed by a breakdown of how asteroseismologists have used these techniques to establish the presence of weakened magnetic braking on the main sequence using asteroseismic data, and what we should be looking forward to from these techniques with the TESS mission., {"references":["Hall, Oliver et al. (2021), Nature Astronomy, Volume 5, p. 707-714","Nielsen, Martin et al. (2015), Astronomy & Astrophysics, Volume 582, id.A10, 5 pp.","Davies, Guy et al. (2015), Monthly Notices of the Royal Astronomical Society, Volume 446, Issue 3, p.2959-2966","Benomar, Othman et al. (2018), Science, Volume 361, Issue 6408, pp. 1231-1234","Silva Aguirre, Victor et al. (2015), Monthly Notices of the Royal Astronomical Society, Volume 452, Issue 2, p.2127-2148","Davies, Guy et al. (2016), Monthly Notices of the Royal Astronomical Society, Volume 456, Issue 2, p.2183-2195","Lund, Mikkel et al. (2017), The Astrophysical Journal, Volume 835, Issue 2, article id. 172, 31 pp.","Silva Aguirre, Victor et al. (2017), The Astrophysical Journal, Volume 835, Issue 2, article id. 173, 18 pp.","Lund, Mikkel et al. (2014), The Astrophysical Journal, Volume 790, Issue 2, article id. 121, 28 pp.","David, Trevor et al. (2022), The Astrophysical Journal, Volume 933, Issue 1, id.114, 22 pp."]}

Melville, en tant que marin, a souvent exprimé son goût pour l’astronomie, les éphémérides et leurs ressources narratologiques : cette fascination se manifeste dans le système métaphorique qui sous-tend toute la structure de Mardi et le monde qu’il parcourt : ce périple prend sens si l’on considère que le héros voyage dans l’orbite des étoiles. Melville avait lu de nombreux « voyages dans la lune », et son roman pourrait être directement inspiré des œuvres de Cyrano de Bergerac, Kepler ou Godwin. En outre, au moment où il écrit ses romans polynésiens, les questions astronomiques sont d’actualité avec le passage de la comète de Halley en particulier, ce nom étant le palindrome presque parfait du nom de l’héroïne Yillah—ce qui permet de lire l’ensemble du roman comme une vaste métaphore astronomique touchant le sens du roman dans son ensemble, à interpréter comme un voyage dans les astres, en particulier dans le monde planétaire de Mardi et de l’anneau de ses îles. Melville as a sailor expressed his fascination for astronomy, ephemerides and their creative potential, which is evidenced in the metaphorical setting that structures the whole argument of Mardi ’s confusing world. Indeed, the hero sails on the orbit of stars. Melville had read many “travels to the moon,” and his novel might be directly inspired by Cyrano de Bergerac, Kepler or Godwin. Moreover, at the time he was writing his Polynesian novels, Melville could not ignore astronomical topics such as the passage of Halley’s comet. Its name is the nearly perfect palindrome of Yillah, which imparts a major metaphorical and celestial dimension to the topography of Mardi and its rings of islands. Instead of being a travelogue-satire, the entire novel operates as an astronomical metaphor.

Johannes Kepler is often cited as a witness to scholars’ resistance to the shift from Latin to vernacular languages in the scientific literature in the early 17th century. Allegedly he was unable to read Italian, and reacted to Galileo's transition from Latin to Italian by accusing him of committing a crimen laesae humanitatis, with the double sense of “crime against humanity” and “crime against classical scholarship”. The paper shows that this claim is groundless. The arguments are as follows: 1. Kepler's alledged remark about Galileo is not documented in Kepler's works. 2. Kepler was very well able to read Italian books. 3. The expression crimen laesae humanitatis is not attested in the neo‐Latin literature of the 17th century 4. All the references of this statement can be traced back to a book by the Heidelberg professor of Romance Studies Leonardo Olschki of 1922, who did not mark the expression as a quotation and who did not give any source reference. 5. Kepler himself published scientific texts in his native German and contributed to the development of a German astronomical terminology.

We present the first short-duration candidate microlensing events from the Kepler K2 mission. From late April to early July 2016, Campaign 9 of K2 obtained high temporal cadence observations over a 3.7 square degree region of the Galactic bulge. Its primary objectives were to look for evidence of a free-floating planet (FFP) population using microlensing, and demonstrate the feasibility of space-based planetary microlensing surveys. Though Kepler K2 is far from optimal for microlensing, the recently developed MCPM photometric pipeline enables us to identify and model microlensing events. We describe our blind event-selection pipeline in detail and use it to recover 22 short-duration events with effective timescales of less than 10 days previously announced by the OGLE and KMTNet ground-based surveys. We also announce five new candidate events. One of these is a caustic-crossing binary event, consistent with a bound planet and modelled as such in a companion study. The other four have very short durations (effective timescales less than 0.1 days) typical of an Earth-mass FFP population. Whilst Kepler was not designed for crowded-field photometry, the K2C9 dataset clearly demonstrates the feasibility of conducting blind space-based microlensing surveys towards the Galactic bulge., Comment: 25 pages including appendices, published MNRAS

In Chapter 16 of Astronomia nova, Kepler describes and applies a method for finding the parameters of what he will call the vicarious hypothesis: a model that still assumes circular orbits and an equant point, but does not assume the bisection of the eccentricity, that is, that the center of the orbit is halfway between the equant point and the Sun. The method allows Kepler to find independently both centers in a very elegant way, but its application is tedious. He confesses that he had to apply it seventy times over a period of 5 years to obtain trustable results. Years earlier, when Kepler arrived to work with Tycho, he found that Tycho and Longomontanus had rejected bisection and somehow had obtained a ratio between eccentricities that, as Kepler himself highlights, happened to be very close to the one Kepler would later find after so much effort. Kepler does not say how Tycho and Longomontanus obtained their parameters and, to the best of my knowledge, there is no single published work that attempts to answer this question. Still, it is a very interesting question to ask how they arrived at values so close to those that took so much pain for Kepler to obtain. Recently, I published a paper describing a method Tycho used for finding Saturn’s parameters. In this paper, I show that by applying this method to the data of Tychonic observations of oppositions, it is possible to arrive at parameters very close to those that we know Tycho found. In this way, I argue that this is the method Tycho applied for obtaining Mars’s parameters. The simplicity of the Tychonic method contrasts with the complexity of Kepler’s.

This paper discusses measurements of the apparent diameter and parallax of the star Sirius, made in the early 18th century by Jacques Cassini, and how those measurements were discussed by other writers. Of particular interest is how other writers accepted Cassini’s measurements, but then discussed Sirius and other stars as though they were all the same size as the sun. Cassini’s measurements, by contrast, required Sirius and other stars to dwarf the sun—something Cassini explicitly noted, and something that echoed the ideas of Johannes Kepler more than a century earlier.

In the present work, in order to estimate the semi-amplitude of the radial velocity, we evaluate the contribution of the Doppler beaming effect to the phase curves of the all confirmed extrasolar planets (2776, September 2019), observed so far by the Kepler telescope. By modeling the tiny photometric variations (reflection, ellipsoidal and Doppler beaming effects) of the light curves, we found that the best observational data are in close agreement with the theoretical and published values of the amplitudes only for exoplanets: KOI-13b and TrES-2b. The derived values for the radial velocity also are in good agreement with those published by some authors. Furthermore, we found it necessary to introduce a third harmonic (3Φ) contribution into the KOI-13b and HAT-P7b light curve models, in order to decrease the residuals.

Johannes Kepler is considered to be the first scholar to have offered an adequate description of heavenly phenomena observed on the Moon's sky. Kepler outlined his ideas in his Somnium ( The Dream ), written originally in 1609, and subsequently printed in the years 1630/34. Kepler's lunar astronomy was to expose the absurdity of the arguments that the geocentric theatre of heavenly phenomena proves that the Earth remains motionless. In this paper, I argue that at the turn of the seventeenth century the idea of the sky observed from the Moon's surface was explored in cosmological discourse far more often than it has been assumed so far. My argument derives from the manuscript treatise Astrostereon (1603) authored by an English astrologer and physician, Edward Gresham. Writing for the same purpose as Kepler but several years earlier, Gresham laid down the foundation of lunar astronomy. I also demonstrate the uses of lunar astronomy in astrological almanacs printed in London at the time when Kepler's ideas were not widely known.

When our school implemented AP Physics 1, I wanted to include a project that would extend over time, use more advanced data analysis, and teach students about handling experimental error. Using a donated 5-inch Newtonian telescope and an entry-level digital camera, the students gathered data from digital images of the four Galilean moons, Io, Europa, Ganymede, and Callisto (see Fig. 1), to verify Kepler’s third law of planetary motion (T2=Kr3). Simulation software could have been used. Among others, Project CLEA (Contemporary Laboratory Experiences in Astronomy) seems to be a favorite that includes verifying Kepler’s third law using the orbits of the Galilean moons. Galileo measured the moons’ periods with his telescope. My students could do the same with modern equipment. The investigation started with a purely Keplerian analysis of the data, then to a Newtonian analysis leading to accurate orbital properties of the Galilean moons and Jupiter’s mass. Once the images have been obtained, they can be used each year.

We examine the origins of the Kepler 36 planetary system, which features two very different planets: Kepler 36b ($\rm \rho = 7.46$ $\rm g$ $\rm cm^{-3}$) and Kepler 36c ($\rm \rho = 0.89$ $\rm g$ $\rm cm^{-3}$). The planets lie extremely close to one another, separated by just 0.01 au, and they orbit just a tenth of an au from the host star. In our origin scenario, Kepler 36b starts with far less mass than Kepler 36c, a gaseous giant planet that forms outside the ice line and quickly migrates inwards, capturing its neighbour into its 2:1 mean-motion resonance while continuing to move inwards through a swarm of planetesimals and protoplanets. Subsequent collisions with these smaller bodies knock Kepler 36b out of resonance and raise its mass and density (via self-compression). We find that our scenario can yield planets whose period ratio matches that of Kepler 36b and c, although these successes are rare, occurring in just 1.2 per cent of cases. However, since systems like Kepler 36 are themselves rare, this is not necessarily a drawback.

If a transiting exoplanet has a moon, that moon could be detected directly from the transit it produces itself, or indirectly via the transit timing variations it produces in its parent planet. There is a range of parameter space where the Kepler Space Telescope is sensitive to the TTVs exomoons might produce, though the moons themselves would be too small to detect photometrically via their own transits. The Earth's Moon, for example, produces TTVs of 2.6 minutes amplitude by causing our planet to move around their mutual centre of mass. This is more than Kepler's short-cadence interval of 1 minute and so nominally detectable (if transit timings can be measured with comparable accuracy), even though the Moon's transit signature is only 7% that of Earth's, well below Kepler's nominal photometric threshold. Here we examine several Kepler systems, exploring the hypothesis that an exomoon could be detected solely from the TTVs it induces on its host planet. We compare this with the alternate hypothesis that the TTVs are caused by an non-transiting planet in the system. We examine 13 Kepler systems and find 8 where both hypotheses explain the observed TTVs equally well. Though no definitive exomoon detection can be claimed on this basis, the observations are nevertheless completely consistent with a dynamically stable moon small enough to fall below Kepler's photometric threshold for transit detection, and these systems warrant further observation and analysis., 17 pages. 15 figures. Accepted for publication on November 26, 2020, by the Monthly Notices of the Royal Astronomical Society

We discuss the current state of problems associated with the discovery and study of exocomets, i.e objects of extrasolar systems, that are in many aspects similar to the solar system comets. Thus far, more than 4,300 exoplanetary systems have been discovered, but little is known about the populations of subplanetary bodies in these systems, in particular comets. Existing theories of planet formation suggest that populations of small bodies in the planetary systems should be numerous, especially at the early stages of their formation. Currently, most of the stars observed with the confirmed transit exoplanets and candidate stars with exoplanetary systems have been collected in the Kepler and TESS space mi- ssion databases. These databases can be used for a search and study of the exocomet transit signatures in extrasolar systems. So far, the number of observed cases of exocomet transits has been small, only about 20 events. Due to the rapid accumulation of data, new researches aimed to identify the specific transit events and study the physical characteristics of small bodies in the extrasolar systems are of great importance.Worth considering is the concept of “falling evaporating bodies”, massive enough bodies surrounded by mini- atmospheres, which fall on the parent star. The events might produce the variable, short-time red-shifts of some spectral features in their spectra. Alternative evidence of exocomet transits can be obtained by detection of the cometary emissions in CO, C, and O lines in the millimeter region of the spectra of debris disks by the ALMA and APEX telescopes. We discuss the known detection methods based on the analysis of the photometric and spectral series of observational data of space missions and ground- based complexes. Some results of experimental studi- es of the exocometary transit signatures obtained by other authors are presented and discussed.

The K2 mission of the Kepler Space Telescope offers a unique possibility to examine sources of both Galactic and Extra-galactic origin with high cadence photometry. Alongside the multitude of supernovae and quasars detected within targeted galaxies, it is likely that Kepler has serendipitously observed many transients throughout K2. Such events will likely have occurred in background pixels, coincidentally surrounding science targets. Analysing the background pixels presents the possibility to conduct a high cadence survey with areas of a few square degrees per campaign. We demonstrate the capacity to independently recover key K2 transients such as KSN 2015K and SN 2018oh. With this survey, we expect to detect numerous transients and determine the first comprehensive rates for transients with lifetimes $\leq1$ day., 13 pages, 10 figures, 4 tables

Tycho Brahe was not just an observer; he was a skilled theoretical astronomer, as his lunar and solar models show. Still, even if he is recognized for proposing the Geoheliocentric system, little do we know of the technical details of his planetary models, probably because he died before publishing the last two volumes of his Astronomiae Instaurandae Progymnasmata, which he planned to devote to the planets. As it happens, however, there are some extant drafts of his calculations in Dreyer’s edition of Tycho’s Opera Omnia under the name Calculi ad Corrigenda Elementa orbitae Saturni, which, to the best of my knowledge, have not yet been analyzed before. In these manuscripts, Tycho starts with calculations based on the Prutenic Tables and makes a series of adjustments to the mean longitude, the longitude of the apogee, and the eccentricity to fit a series of observations of oppositions. In doing that, Tycho (1) describes and applies a new method for obtaining accurate values for the parameters of the superior planets, he (2) develops a divided eccentricity (not bisected) model of Saturn, similar to the one we know Longomontanus and Kepler applied to Mars, and finally (3) he realizes that the true position of the Sun somehow affects the motion of Saturn around the zodiac and develops a method to correct the position of Saturn as a function of solar equation of anomaly. So, a close analysis of the calculations reveals details of the Tychonic planetary models unknown until now. The present study analyzes these drafts.

The eclipsing binary system EPIC 201826968 was imaged using the Las Cumbres Observatory Global Telescope Network with Bessel-B, Bessel-V, SDSS-r0 and SDSS-i0 filters. AstroImageJ was used to determine the optimal exposure time for the images. We coded a phase-dispersion minimization (PDM) algorithm and compared its result to PyAstronomy’s PDM algorithm and both PyAstronomy’s and Astropy’s Lomb-Scargle algorithms. Our distance PDM algorithm gave a period of 0.3617673 days, while the PyAstronomy PDM gave 0.3617724 days. The Lomb-Scargle algorithms both gave very different periods of near 1.83 days, possibly due to Lomb-Scargle’s reliance on a sinusoidal fit. Since Kepler measured a period of 0.3617589 days, and the average period from the Python-coded and PyAstronomy PDM algorithms deviated from it by less than a second, we concluded that the period of eclipsing binary system EPIC 201826968 hasnot changed since Kepler’s observations.

In this study we observed and determined the period of the eclipsing binary star EPIC 201458798, finding that its period has not changed since it was last measured and published in the Kepler catalog in 2014. We did this by developing Python code to determine the period using two independent algorithms and partially automating the search for suitable comparison stars. Our system was imaged by the 0.4m Las Cumbres Observatory telescopes in four filters. We analyzed six photometry types returned for each image from the Our Solar Siblings pipeline. Of these photometries, we found source extractor kron (sek) to be the most appropriate type for our 2x2 binned images of EPIC 201458798. Both of the period-finding algorithms we developed gave results that were not statistically different from the Kepler catalog period for the infrared, red, and visual filter images. The blue filter images were statistically different fromthe Kepler catalog period for one of our algorithms but not the other.

In this work, we investigate configuration formation of two inner terrestrial planets near mean motion resonance (MMRs) induced by the perturbation of a distant gas-giant for the Kepler-68 system, by conducting thousands of numerical simulations. The results show that the formation of terrestrial planets is relevant to the speed of Type I migration, the mass of planets, and the existence of giant planet. The mass and eccentricity of the giant planet may play a crucial role in shaping the final configuration of the system. The inner planet pair can be trapped in 5:3 or 7:4 MMRs if the giant planet revolves the central star with an eccentric orbit, which is similar to the observed configuration of Kepler-68. Moreover, we find that the eccentricity of the middle planet can be excited to roughly 0.2 if the giant planet is more massive than 5 $M_J$,otherwise the terrestrial planets are inclined to remain near-circular orbits. Our study may provide a likely formation scenario for the planetary systems that harbor several terrestrial planets near MMRs inside and one gas-giant exterior to them., Comment: 13 pages, 8 figures, accepted for publication in MNRAS

When at the beginning of 1600, Kepler arrived to work with Tycho Brahe, Longomontanus, Tycho’s principal assistant, who was working with a model for Mars that predicted with remarkable accuracy its longitudes at oppositions. According to Kepler, this hypothesis “represented all these oppositions within a distance of two minutes in longitude.” The model, however, was unsuccessful in predicting longitudes at other elongations from the Sun, and latitudes even at opposition. Much has been said on how Kepler developed his model after this meeting, arriving finally at the so-called first two laws published in his Astronomia Nova in 1609. By contrast, Longomontanus’ attempt, published as a final model in his Astronomia Danica, has received little scholarly attention. In this paper, I will systematically analyse and explain this model. Even if Longomontanus’ solution is not as elegant as Kepler’s, it deserves scholarly attention, both because it solves the problems posed by the model that he and Tycho were working on when Kepler arrived and because it offers an interesting though heterodox solution that, by contrast, helps to highlight the elegance and simplicity of Kepler’s own solution.

Based on many years of experience in the organization of the third stage of Ukrainian National Astronomy Olympiad, the authors of the article attempt to formulate general principles for the selection and compilation of astronomy olympiad problems, as well as to demonstrate the application of the described principles on the example of astronomy olympiads in Ivano-Frankivsk region. The peculiarities of school Olympiad in astronomy, the purpose of their conduct, the specificity of task packages, including necessity for differentiation by complexity and topics, were analyzed. A characteristic feature of the Olympiad tasks is their non-standard nature, necessity to use methods that are unusual for students to solve problems. On the other hand, such tasks should match intellectual development of the competition participants, and the course of the solution should be accessible to understanding and should not require knowledge of a university program. In particular, on the basis of the analysis by the authors of the process of compiling astronomy Olympiad tasks, which were offered to students in the past years at the regional stage of the student Olympiads, were identified, the methods of their creation were systematized and characterized. Each method contains a detailed explanation, justification for its use and examples, both analytical and practical. For the sake of clarity, the topic “Kepler Laws” was choosen for Olympiad problems, which were analyzed and methods used to create them were described. This topic is one of the fundamental in the schoolar astronomy, which determines both the need to include such tasks in the Olympiad program and the complexity of their choice, and creation, because the topic is narrow enough and is qualitatively covered in various textbooks and collections of problems.

Solar-type stars in eclipsing binaries are proving to be a remarkable resource of knowledge for testing models of stellar evolution, as spectroscopic and photometric studies have opened up a window into their interiors. Until recently, many cases have been worked out with Kepler data. in an ongoing effort to elucidate this research, we examine five detached eclipsing binaries, selected from the Kepler catalogue. There is a well-known stellar parameter discrepancy for low-mass stars, in that the observed radii and masses are often larger and stars overluminous than predicted by theory by several per cent. in our samples, we found five double-lined binaries, with solar-type stars dominating the spectrum. the orbital and light-curve solutions were found for them, and compared with isochrones, in order to estimate absolute physical parameters and evolutionary status of the components. An important aspect of this work is that the calculated stellar radii and masses are consistent with theoretical models within the uncertainties, whereas the estimated temperatures from the disentangled spectra of the components are no different than predicted., ESO [089.D-0097(B), 091.D-0145(B), 094.A-9029(R), 098.D-0076(A), 0100.D-0339(B), 0100.D-0273(A)]; NASA's Science Mission Directorate; National Aeronautics and Space AdministrationNational Aeronautics & Space Administration (NASA); National Science FoundationNational Science Foundation (NSF); Ege University Research FoundationEge University [FDK-2019-20215], This research made use of data collected at ESO under programmes 089.D-0097(B) and 091.D-0145(B) (by K. Helminiak), 094.A-9029(R) (by R. Gredel), 098.D-0076(A) (by J. Southworth), 0100.D-0339(B) (by G. Pietrzynski), 0100.D-0273(A) (by W. Gieren). This work is based on data from the Kepler mission. Kepler was competitively selected as the tenth Discovery mission. Funding for this mission is provided by NASA's Science Mission Directorate. the photometric data were obtained from the Mikulski Archive for Space Telescopes (MAST). This work has also made use of data from the European Space Agency (ESA) mission Gaia (http://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, http://www.cosmos.esa.int/web/gaia/dpac/consortium).This publication makes use of data products from the Two Micron All Sky Survey, which is a joint project of the University of Massachusetts and the Infrared Processing andAnalysis Center/California Institute of Technology, funded by the National Aeronautics and Space Administration and the National Science Foundation. We thank Ege University Research Foundation (Project No. FDK-2019-20215) for supporting this study. the authors express their sincere thanks to an anonymous referee whose valuable comments led to an improvement of the paper. This article is a part of the PhD thesis of B. Hoyman. the following internet-based resources were used in research for this paper: the NASA Astrophysics Data System; the SIMBAD data base operated at CDS, Strasbourg, France.

The great astronomer linked the speed of planetary orbits to musical scales—and to the harmonious interaction of humans on Earth during a time of religious warfare.

International audience; We present the analysis of the multi-planetary system Kepler-117, which is part of our program of observations of Kepler planets. This system is composed of a ~ 30 MEarth planet in a ~ 19 days orbit and a ~ 2 MJ planet orbiting in ~ 51 days. Both the orbits have low eccentricity. The planets are not close to an exact low-order mean motion resonance, but exhibit significant transit timing variations (TTVs) nevertheless. We perform a combined Markov Chain Monte Carlo fit on all the available data: the Kepler photometry, the TTVs, the radial velocities we obtained with SOPHIE/OHP and the stellar parameters. The prime result is that the modelling of the TTVs allows to increase the precision on the system parameters which are not constrained by the radial velocities alone.

In the first chapter of his Astronomia Nova, Kepler introduced a diagram that, he claimed, represents the path of Mars between 1580 and 1596, assuming a resting Earth. In the words of Willi...

Taking advantage of the unparalleled quantity and quality of high-cadence Kepler light curves of several dwarf novae, the strength of the flickering and the high-frequency spectral index of their power spectra are investigated as a function of magnitude around the outburst cycle of these systems. Previous work suggesting that the flickering strength (on a magnitude scale) is practically constant above a given brightness threshold and only rises at fainter magnitudes is confirmed for most of the investigated systems. As a new feature, a hysteresis in the flickering strength is seen in the sense that at the same magnitude level flickering is stronger during decline from outburst than during the rise. A similar hysteresis is also seen in the spectral index. In both cases, it can qualitatively be explained under plausible assumptions within the disc instability model model for dwarf nova outbursts.

Data from the Transiting Exoplanet Survey Satellite (TESS) has produced of order one million light curves at cadences of 120 s and especially 1800 s for every ~27-day observing sector during its two-year nominal mission. These data constitute a treasure trove for the study of stellar variability and exoplanets. However, to fully utilize the data in such studies a proper removal of systematic noise sources must be performed before any analysis. The TESS Data for Asteroseismology (T'DA) group is tasked with providing analysis-ready data for the TESS Asteroseismic Science Consortium, which covers the full spectrum of stellar variability types, including stellar oscillations and pulsations, spanning a wide range of variability timescales and amplitudes. We present here the two current implementations for co-trending of raw photometric light curves from TESS, which cover different regimes of variability to serve the entire seismic community. We find performance in terms of commonly used noise statistics to meet expectations and to be applicable to a wide range of different intrinsic variability types. Further, we find that the correction of light curves from a full sector of data can be completed well within a few days, meaning that when running in steady-state our routines are able to process one sector before data from the next arrives. Our pipeline is open-source and all processed data will be made available on TASOC and MAST., 27 pages, 15 figures, accepted for publication in The Astrophysical Journal Supplement Series

The NASA Transiting Exoplanet Survey Satellite (TESS) is observing tens of millions of stars with time spans ranging from $\sim$ 27 days to about 1 year of continuous observations. This vast amount of data contains a wealth of information for variability, exoplanet, and stellar astrophysics studies but requires a number of processing steps before it can be fully utilized. In order to efficiently process all the TESS data and make it available to the wider scientific community, the TESS Data for Asteroseismology working group, as part of the TESS Asteroseismic Science Consortium, has created an automated open-source processing pipeline to produce light curves corrected for systematics from the short- and long-cadence raw photometry data and to classify these according to stellar variability type. We will process all stars down to a TESS magnitude of 15. This paper is the next in a series detailing how the pipeline works. Here, we present our methodology for the automatic variability classification of TESS photometry using an ensemble of supervised learners that are combined into a metaclassifier. We successfully validate our method using a carefully constructed labelled sample of Kepler Q9 light curves with a 27.4 days time span mimicking single-sector TESS observations, on which we obtain an overall accuracy of 94.9%. We demonstrate that our methodology can successfully classify stars outside of our labeled sample by applying it to all $\sim$ 167,000 stars observed in Q9 of the Kepler space mission., 35 pages, 17 figures, 6 tables, Accepted for publication in The Astronomical Journal

A supernova close enough to the Earth is a spectacular event: it can appear as a \new star" as luminous as Venus, or even more, visible for several days. The rate of Galactic supernovae is expected to be of about one in 30 years, with a fraction visible at naked eye; however in all the history of human civilization only seven supernovae in the Milky Way have been reported, the last two (1572 and 1604) during Galilei's life. The supernova of 1604, today called Kepler's Supernova, was observed by Galilei, Kepler and other astronomers in Europe, Korea, and China. Like the supernova SN1572, today called Tycho's supernova, it has been the subject of extensive studies, and inspired observational measurements and philosophical considerations on the nature of the heavens. The remnant of SN1604 has been indicated by recent X- and gamma-ray data to be a likely site of cosmic ray acceleration. The first recorded data of optical observations, together with new data, can still tell us a lot about the early evolution of this supernova.

There has been a rapid increase in astronomical data in terms of both size and complexity. To process this extremely large amount of data, machine learning and deep learning methods can be instrumental in arriving at results and further processing relevant data needed by the researchers. In this project, the Inception V3 and Faster RCNN models are employed for determining the morphological type of galaxies along with detection of galaxies in images for the Galaxy Zoo dataset. For detecting the exoplanets, Astronet is used to determine whether the astronomical body is an exoplanet or not on the Kepler time series data. The machine learning method: SGD classifier is predicting the exoplanet habitability, which is tested on PHL’s exoplanet catalogue.

Early analyses of exoplanet statistics from the Kepler Mission revealed that a model population of multiple-planet systems with low mutual inclinations (${\sim1^{\circ}-2^{\circ}}$) adequately describes the multiple-transiting systems but underpredicts the number of single-transiting systems. This so-called "Kepler dichotomy" signals the existence of a sub-population of multi-planet systems possessing larger mutual inclinations. However, the details of these inclinations remain uncertain. In this work, we derive constraints on the intrinsic mutual inclination distribution by statistically exploiting Transit Duration Variations (TDVs) of the Kepler planet population. When planetary orbits are mutually inclined, planet-planet interactions cause orbital precession, which can lead to detectable long-term changes in transit durations. These TDV signals are inclination-sensitive and have been detected for roughly two dozen Kepler planets. We compare the properties of the Kepler observed TDV detections to TDV detections of simulated planetary systems constructed from two population models with differing assumptions about the mutual inclination distribution. We find strong evidence for a continuous distribution of relatively low mutual inclinations that is well-characterized by a power law relationship between the median mutual inclination ($\tilde{\mu}_{i,n}$) and the intrinsic multiplicity ($n$): $\tilde{\mu}_{i,n} = \tilde{\mu}_{i,5}(n/5)^{\alpha}$, where $\tilde{\mu}_{i,5} = 1.10^{+0.15}_{-0.11}$ and $\alpha = -1.73^{+0.09}_{-0.08}$. These results suggest that late-stage planet assembly and possibly stellar oblateness are the dominant physical origins for the excitation of Kepler planet mutual inclinations., Comment: Accepted to AJ, 19 pages, 10 figures (excluding appendix)

The word ’Geocentric’ comes from the Greek word Γeωκeντρικό which is a compound word composed from two words: “γeω” means Earth and “κeντρικό” 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 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.

The stellar magnetic field is the driver of activity in the star and can trigger energetic flares, CMEs and ionized wind. These phenomena, specially CMEs, may have an important impact on the magnetosphere and atmosphere of the orbiting planets. To predict whether a CME will impact a planet, the effects of the background on the CME's trajectory must be taken into account. We used the MHD code ForeCAT – a model for CME deflection due to magnetic forces – to perform numerical simulations of CMEs being launched from both the Sun and Kepler-63, which is a young, solar-like star with high activity. Comparing results from Kepler-63 and the Sun gives us a panorama of the distinct activity level and star-planet interactions of these systems due to the difference of stellar ages and star-planet distances.

Protoplanetary disks are thought to be truncated at orbital periods of around 10 days. Therefore, origin of rocky short period planets with $P < 10$ days is a puzzle. We propose that many of these planets may form through the Type-I migration of planets locked into a chain of mutual mean motion resonances. We ran N-body simulations of planetary embryos embedded in a protoplanetary disk. The embryos experienced gravitational scatterings, collisions, disk torques, and dampening of orbital eccentricity and inclination. We then modelled Kepler observations of these planets using a forward model of both the transit probability and the detection efficiency of the Kepler pipeline. We found that planets become locked into long chains of mean motion resonances that migrate in unison. When the chain reaches the edge of the disk, the inner planets are pushed past the edge due to the disk torques acting on the planets farther out in the chain. Our simulated systems successfully reproduce the observed period distribution of short period Kepler planets between 1 and 2 $R_\oplus$. However, we obtain fewer closely packed short period planets than in the Kepler sample. Our results provide valuable insight into the planet formation process, and suggests that resonance locks, migration, and dynamical instabilities play important roles the the formation and evolution of close-in small exoplanets., 12 pages, 11 figures, submitted to MNRAS

The photometric precision, monitoring baselines, and rapid, even sampling rates required by modern satellites designed for detecting the signal of transiting exoplanets are ideally suited to a large number of applications in high-energy astrophysics. I will exemplify this by discussing the results for active galactic nuclei from Kepler and summarizing other high-energy results from Kepler/K2. These precision instruments are currently underutilized for high-energy applications despite their great potential, due in part to complex systematics affecting the data. I will summarize these effects and mitigation approaches, and conclude by discussing how the recently launched Transiting Exoplanet Survey Satellite mission will differ from Kepler/K2 in ways significant to the high-energy community., Comment: Accepted for publication in Astronomische Nachrichten. Conference Proceedings from "Time-Domain Astronomy: A High Energy View", June 13-15 2018, ESAC, Madrid, Spain

Proceeding of a contributed talk given at the meeting: "TIME-DOMAIN ASTRONOMY: A HIGH ENERGY VIEW" held at ESAC, Madrid, 13 - 15 JUNE 2018 Together with coronal mass ejection, flares are the most energetic stellar magnetic events, ignited by a sudden release of magnetic energy, which triggers a cascade of interconnected phenomena, each resulting in emission in different bands. For this reason, flares are intrinsic multiwavelength phenomena. In particular, optical and soft X-ray emission probes two different events occurring during flares: the heating of plasma in the upper photosphere at the footpoints of the magnetic loops and the heating and cooling of the plasma confined in the loops in the corona, respectively. To characterize powerful flares observed in optical and X-rays, constrain the energy released in both bands, the geometry of the loops, and to study flares time evolution, we studied the brightest flares occurred in the 125-Myr-old stars in the Pleiades observed simultaneously with x-ray multi-mirror mission/Newton and Kepler/K2.

A primary goal of general education introductory astronomy courses often is to provide students with examples of how science is actually done. Low to nonexistent mathematical prerequisites in some courses can make useful exercises difficult to find, and sometimes very difficult for students, especially if the exercises feature quantitative components. What follows describes an attempt to meet this goal through the use of actual exoplanet data, available online, from the NASA Kepler Mission. The exercise described guides the students through an aspect of scientific investigation that they may otherwise not experience, the handling and analysis of a large set of actual scientific data.