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Full list of authors: Santos-Sanz, P.; Ortiz, J. L.; Sicardy, B.; Popescu, M.; Benedetti-Rossi, G.; Morales, N.; Vara-Lubiano, M.; Camargo, J. I. B.; Pereira, C. L.; Rommel, F. L.; Assafin, M.; Desmars, J.; Braga-Ribas, F.; Duffard, R.; Marques Oliveira, J.; Vieira-Martins, R.; Fernández-Valenzuela, E.; Morgado, B. E.; Acar, M.; Anghel, S.; Atalay, E.; Ateş, A.; Bakiş, H.; Bakis, V.; Eker, Z.; Erece, O.; Kaspi, S.; Kayhan, C.; Kilic, S. E.; Kilic, Y.; Manulis, I.; Nedelcu, D. A.; Niaei, M. S.; Nir, G.; Ofek, E.; Ozisik, T.; Petrescu, E.; Satir, O.; Solmaz, A.; Sonka, A.; Tekes, M.; Unsalan, O.; Yesilyaprak, C.; Anghel, R.; Berteşteanu, D.; Curelaru, L.; Danescu, C.; Dumitrescu, V.; Gherase, R.; Hudin, L.; Stoian, A. -M.; Tercu, J. O.; Truta, R.; Turcu, V.; Vantdevara, C.; Belskaya, I.; Dementiev, T. O.; Gazeas, K.; Karampotsiou, S.; Kashuba, V.; Kiss, Cs.; Koshkin, N.; Kozhukhov, O. M.; Krugly, Y.; Lecacheux, J.; Pal, A.; Püsküllü, Ç.; Szakats, R.; Zhukov, V.; Bamberger, D.; Mondon, B.; Perelló, C.; Pratt, A.; Schnabel, C.; Selva, A.; Teng, J. P.; Tigani, K.; Tsamis, V.; Weber, C.; Wells, G.; Kalkan, S.; Kudak, V.; Marciniak, A.; Ogloza, W.; Özdemir, T.; Pakštiene, E.; Perig, V.; Żejmo, M.--This is an Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited., Context. As part of our international program aimed at obtaining accurate physical properties of trans-Neptunian objects (TNOs), we predicted a stellar occultation by the TNO (38628) Huya of the star Gaia DR2 4352760586390566400 (mG = 11.5 mag) on March 18, 2019. After an extensive observational campaign geared at obtaining the astrometric data, we updated the prediction and found it favorable to central Europe. Therefore, we mobilized half a hundred of professional and amateur astronomers in this region and the occultation was finally detected by 21 telescopes located at 18 sites in Europe and Asia. This places the Huya event among the best ever observed stellar occultation by a TNO in terms of the number of chords. Aims. The aim of our work is to determine an accurate size, shape, and geometric albedo for the TNO (38628) Huya by using the observations obtained from a multi-chord stellar occultation. We also aim to provide constraints on the density and other internal properties of this TNO. Methods. The 21 positive detections of the occultation by Huya allowed us to obtain well-separated chords which permitted us to fit an ellipse for the limb of the body at the moment of the occultation (i.e., the instantaneous limb) with kilometric accuracy. Results. The projected semi-major and minor axes of the best ellipse fit obtained using the occultation data are (a′, b′) = (217.6 ± 3.5 km, 194.1 ± 6.1 km) with a position angle for the minor axis of P′ = 55.2° ± 9.1. From this fit, the projected area-equivalent diameter is 411.0 ± 7.3 km. This diameter is compatible with the equivalent diameter for Huya obtained from radiometric techniques (D = 406 ± 16 km). From this instantaneous limb, we obtained the geometric albedo for Huya (pV = 0.079 ± 0.004) and we explored possible three-dimensional shapes and constraints to the mass density for this TNO. We did not detect the satellite of Huya through this occultation, but the presence of rings or debris around Huya was constrained using the occultation data. We also derived an upper limit for a putative Pluto-like global atmosphere of about psurf = 10 nbar. © P. Santos-Sanz et al. 2022., P.S-S. acknowledges financial support by the Spanish grant AYA-RTI2018-098657-J-I00 “LEO-SBNAF” (MCIU/AEI/FEDER, UE). P.S-S., J.L.O., N.M., M.V-L. and R.D. acknowledge financial support from the State Agency for Research of the Spanish MCIU through the “Center of Excellence Severo Ochoa” award for the Instituto de Astrofísica de Andalucía (SEV-2017-0709), they also acknowledge the financial support by the Spanish grants AYA-2017-84637-R and PID2020-112789GB-I00, and the Proyectos de Excelencia de la Junta de Andalucía 2012-FQM1776 and PY20-01309. The research leading to these results has received funding from the European Union’s Horizon 2020 Research and Innovation Programme, under Grant Agreement no. 687378, as part of the project “Small Bodies Near and Far” (SBNAF). Part of the research leading to these results has received funding from the European Research Council under the European Community’s H2020 (2014-2020/ERC Grant Agreement no. 669416 “LUCKY STAR”). Part of the work of M.P. was financed by a grant of the Romanian National Authority for Scientific Research and Innovation, CNCS – UEFISCDI PN-III-P1-1.1-TE-2019-1504. This study was financed in part by the Coordenaçâo de Aperfeiçoamento de Pessoal de Nível Superior – Brasil (CAPES) – Finance Code 001 and the National Institute of Science and Technology of the e-Universe project (INCT do e-Universo, CNPq grant 465376/2014-2). The following authors acknowledge the respective CNPq grants: F.B-R 309578/2017-5; R.V.-M. 304544/2017-5, 401903/2016-8; J.I.B.C. 308150/2016-3 and 305917/2019-6; M.A 427700/2018-3, 310683/2017-3 and 473002/2013-2; B.E.M. 150612/2020-6. G.B.R. thanks the support of CAPES and FAPERJ/PAPDRJ (E26/203.173/2016) grant. J.M.O. acknowledges financial support from the Portuguese Foundation for Science and Technology (FCT) and the European Social Fund (ESF) through the PhD grant SFRH/BD/131700/2017. E.F-V. acknowledges funding through the Preeminant Postdoctoral Program of the University of Central Florida. C.K., A.P. and R.S. have been supported by the grants K-125015 and K-138962 of the National Research, Development and Innovation Office (NKFIH, Hungary). E.P. acknowledges the Europlanet 2024 RI project funded by the European Union’s Horizon 2020 Research and Innovation Programme (Grant agreement No. 871149). We are grateful to the CAHA and OSN staffs. This research is partially based on observations collected at the Centro Astronómico Hispano Alemán (CAHA) at Calar Alto, operated jointly by Junta de Andalucía and Consejo Superior de Investigaciones Científicas (IAA-CSIC). This research was also partially based on observation carried out at the Observatorio de Sierra Nevada (OSN) operated by Instituto de Astrofísica de Andalucía (CSIC). This article is also based on observations made in the Observatorios de Canarias del IAC with the Liverpool Telescope operated on the island of La Palma by the Instituto de Astrofísica de Canarias in the Observatorio del Roque de los Muchachos. Part of the results were based on observations taken at Pico dos Dias Observatory of the National Laboratory of Astrophysics (LNA/Brazil). Part of the data were collected during the photometric monitoring observations with the robotic and remotely controlled observatory at the University of Athens Observatory – UOAO (Gazeas 2016). We thank the Adiyaman University Astrophysics Application and Research Center for their support in the acquisition of data with the ADYU60 telescope. This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement.

In this study the centaur figure which is known as one of the extraordinary hybrid creatures, is subjected to research in Islamic art with its perceived position in a quite different meaning aspect from western mythology and art. Horse-human hybrid centaur is in the form of a horse from the waist down and a man up to the waist. The relationship between sciences of astronomy and astrology and this figure which is named as kantûrus in Islamic literature, forms its face reflecting directly to the Islamic painting in the meantime. Although some paintings are also encountered about the figure with this perspective in western art, it is known that remains widely at the forefront with its mythological character in this geography. However it is understood that the kantûrus figure is depicted exclusive to representation of zodiac sign (Sagittarius) and constellation (Centaur) in Islamic art. Sagittarius also called the Archer is in the shape of a centaur about the shoot his arrow. Centaur like Sagittarius is represented as half man and half horse. The constellation Centaur also seizes with one hand a wild beast called Lupus by the feet and holds aloft. Besides the other hand of the Centaur holds a bunch of leaves. This constellation is composed of a large number of stars. Some of the stars are on the arrow and the bow and the others on shoulders, legs, feet, knee, hoof or armpit of the centaur. Certain stars are also located in a garment fluttering from his back. On the occasion of this research, some examples in Islamic art from different periods and a variety of works related to the subject are presented and attempted to form a frame for content of this depiction. It is determined that the earliest dated one of the examples was from the beginning of the 8th century and the latest one from the end of 18th century. Among the examples which involve the centaur figure, together with miniatures in manuscripts constitute the majority, examples from stone, metal and ceramic works of art also create a substantial richness. By means of the researched various examples, it is understood that the centaur figure becomes prevalent especially in Seljuk period in Islamic art and geographically the east and southeast of Anatolia and Iran come into prominence. Concerning to the subject another astrological element related with centaur figure is a pseudoplanet called Jawzahar. It is considered that Sagittarius in relation with Jawzahar in the shape of dragon-tail reflect the ascending and descending nodes of the moon. The planet moves to the north is called the ascending node relates to the head of dragon and it moves to the south relates to the tail. In most of the depictions, the Sagittarius associated with a giant serpent or a dragon figure which symbolises Jawzahar referring to the lunar nodes of the moon. Lunar nodes were two opposite point of the moon’s orbit and the ecliptic. Representations of Jawzahar appeared usually in the form of the bow-bending centaur shoots at the dragon attached to its tail. [TR: Sıra dışı melez yaratıklardan biri olarak bilinen kentaur figürü, İslam sanatında batı mitolojisi ve sanatından oldukça farklı bir anlam boyutunda algılanan konumuyla bu çalışmada incelemeye tabi tutulmaktadır. İslam literatüründe kantûrus adıyla anılan bu figürün astronomi ve astroloji ilimleriyle bağlantısı aynı zamanda İslam tasvir sanatına doğrudan yansıyan yüzünü teşkil etmektedir. Her ne kadar batı sanatında da figürün bu yönüyle ele alındığı tasvirlere rastlanmaktaysa da bu coğrafyada büyük ölçüde mitolojik karakteriyle ön planda olduğu bilinmektedir. İslam sanatında ise kantûrus figürünün Yay burcu ve Kantûrus takımyıldızı temsiline münhasır olarak resmedildiği anlaşılmaktadır. Bu araştırma vesilesiyle farklı dönemlere ait çeşitli eserler üzerinden konuya ilişkin örnekler ortaya konulmakta ve tasvirin içeriğine ilişkin bir çerçeve oluşturulmaya çalışılmaktadır. Örneklerin en erken tarihlisinin 8. yüzyılın başlarına, en geç tarihlisinin de 18. yüzyılın sonlarına ait olduğu tespit edilmiştir. Kentaur tasvirini içerdiği belirlenen eserler arasında elyazmalarındaki minyatürler çoğunluğu teşkil etmekle beraber, taş, maden ve seramik sanatından örnekler de önemli bir zenginlik oluşturmaktadır. İncelenen çeşitli eserler vasıtasıyla İslam sanatında kentaur figürünün bilhassa Selçuklu döneminde yoğunlaştığı, coğrafi açıdan ise Anadolu’nun doğusu ve güneydoğusu ile İran’ın önem kazandığı anlaşılmaktadır.]

Context. Saturn has an excess of irregular moons. This is thought to be the result of past collisional events. Debris produced during such episodes in the neighborhood of a host planet can evolve into co-orbitals trapped in quasi-satellite and/or horseshoe resonant states. A recently announced centaur, 2013 VZ70, follows an orbit that could be compatible with those of prograde Saturn's co-orbitals. Aims. We perform an exploration of the short-term dynamical evolution of 2013 VZ70 to confirm or reject a co-orbital relationship with Saturn. A possible connection with Saturn's irregular moon population is also investigated. Methods. We studied the evolution of 2013 VZ70 backward and forward in time using N-body simulations, factoring uncertainties into the calculations. We computed the distribution of mutual nodal distances between this centaur and a sample of moons. Results. We confirm that 2013 VZ70 is currently trapped in a horseshoe resonant state with respect to Saturn but that it is a transient co-orbital. We also find that 2013 VZ70 may become a quasi-satellite of Saturn in the future and that it may experience brief periods of capture as a temporary irregular moon. This centaur might also pass relatively close to known irregular moons of Saturn. Conclusions. Although an origin in trans-Neptunian space is possible, the hostile resonant environment characteristic of Saturn's neighborhood favors a scenario of in situ formation via impact, fragmentation, or tidal disruption as 2013 VZ70 can experience encounters with Saturn at very low relative velocity. An analysis of its orbit within the context of those of the moons of Saturn suggests that 2013 VZ70 could be related to the Inuit group. Also, the mutual nodal distances of 2013 VZ70 and the moons Fornjot and Thrymr are below the first percentile of the distribution., 10 pages, 8 figures, 5 tables, 1 appendix. Accepted for publication in Astronomy and Astrophysics. Abstract abridged. After language edition

BACKGROUND & AIMS The development of accurate non-invasive tests to detect and measure the extent of fibrosis and disease activity in patients with non-alcoholic steatohepatitis (NASH) - the progressive phenotype of non-alcoholic fatty liver disease (NAFLD) - is of great clinical importance. Herein, we aimed to validate the performance of PRO-C3 and ADAPT for the detection of moderate/severe fibrosis within the CENTAUR screening population. METHODS PRO-C3 was assessed in plasma from the screening population of the phase IIb CENTAUR study (NCT02217475) in adults with NASH and liver fibrosis. The relation between PRO-C3 and histologic features of NASH was evaluated, as well as the demographics of patients with high and low levels of PRO-C3. The diagnostic ability of PRO-C3, as a standalone marker or incorporated into ADAPT, to identify patients with F≥2 and NASH was estimated using receiver-operating characteristic analysis and logistic regression models. RESULTS A total of 517 individuals with matched biopsy and PRO-C3 measurements were included. Patients with PRO-C3 levels ≥20.2 ng/ml showed increased levels of insulin, HOMA-IR, alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase, and platelet count compared to patients with low PRO-C3 (p

Two extremely red main-belt asteroids: 203 Pompeja and 269 Justitia, were identified from combined visible and near-infrared spectroscopic observations collected at the IRTF and SAO observatories. These two asteroids have a redder spectral slope than any other D-type body, which are the reddest objects in the asteroid belt, and similar to RR and IR-class objects found in the outer Solar System among trans-Neptunian objects and Centaurs. Spectroscopic results suggest the presence of complex organic materials on the surface layer of these asteroids, implying that they could have formed in the vicinity of Neptune and been transplanted to the main belt region during a phase of planetary migration. 203 Pompeia is the only very red asteroid known so far among the ~250 bodies with diameter larger than 110 km (i.e. presumably structurally intact) found in the asteroid belt. These discoveries add another piece of evidence that the main asteroid belt hosts a population of bodies that were formed in the outskirt of the Solar System., 12 pages, 5 figures, 1 tables, Accepted for publication in ApJ Letters

Katarzyna Marciniak's introductory words explain to the readers the place of the volume "Our Mythical Education: The Reception of Classical Myth Worldwide in Formal Education, 1900–2020", edited by Lisa Maurice, in the context of the "Our Mythical Childhood" project and the book series. The "Foreword" is available also at the Publisher's website, University of Warsaw Press: https://www.wuw.pl/data/links/d3e06046f996d7f6be394a8b02fd2380/14689_8804.pdf Open Access of the complete volume at https://www.wuw.pl/product-eng-14887-Our-Mythical-Education-The-Reception-of-Classical-Myth-Worldwide-in-Formal-Education-1900-2020-PDF.html, This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 Research and Innovation Programme under grant agreement No 681202 (2016–2022), "Our Mythical Childhood... The Reception of Classical Antiquity in Children's and Young Adults' Culture in Response to Regional and Global Challenges", ERC Consolidator Grant led by Katarzyna Marciniak. Project's Website: www.omc.obta.al.uw.edu.pl licensed under CC BY 3.0 PL, https://creativecommons.org/licenses/by/3.0/pl/legalcode

One of the major problems encountered in the analysis of medieval texts mentioning animals is that we sometimes just do not know what “modern” animal they actually refer to. The observation applies not only to imaginary creatures, fantastic beasts such as the siren, the centaur, or the dragon, but to numerous animals that are perfectly identifiable today. Medieval authors can use the name we are familiar with to refer to a different animal or describe an animal in a way that is at odds with present-day concepts, so that we sometimes wonder which beast they had in mind. This chapter will try to present a survey of the problems medievalists face when trying to reconstruct what kind of animal is actually being mentioned in medieval texts.

The purpose of the artistic research, Moving through Choreography – Curating Choreography as an Artistic Practice, has been to consider choreography and curating in their similarities and differences. Thus, at different phases of the working process, choreography and curating were treated as one and the same artistic practice; while, in other moments, as practices that are distinct from each other. Curating has been implemented as a ‘taking care’ principle and a relational activity impacting the production, presentation and documentation of choreography. Choreography has undergone a process of self-reincarnations, or rather, of trans-carnations, whereby the entire body of work has been scrutinized and altered. Key figure/body/agent of these trans-carnations has been the horse, or rather, the assemblage of human and horse, women and horses, here called ‘Centauring.’ Curating and choreography have been integrated to a scrutiny of the art of riding, specifically, the choreography of dressage. In dressage, the research has identified the rigor needed by the research to both steer and unleash the working process. The research has been pursued by purely artistic means, within a circumscribed field. Different perspectives and the making use of ramifications and loose ends, has proliferated into a plethora of intra-related works, objects and choreographies within which research result and artistic result coincide. The research har proceeded in consecutive phases. Each phase has developed its own specific artistic methodologies. The overarching methodology has provided for a clear navigation of undetermined directions and dramaturgies. The concept of ‘One’ has produced and collected both core outcomes and residual manifestations. The exhibitions and the exhibitor have carried, pursued and embodied the works and otherwise choreographies, throughout the research process. Examensbenämning: Konstnärlig doktorsexamen i performativa och mediala praktiker Engelsk examensbenämning: Degree of Doctor of Philosophy in Fine Arts in Performative and Media Based Practices. The Documented Artistic Research Project (Doctoral Thesis) - Moving through Choreography – Curating Choreography as an Artistic Practice - consists of five interrelated parts: To be made public in DiVA February 13th 2021o Centauring - A curated and choreographed exhibition including video documentation of the live performance ONE – I leave the skin dead and dry shining light behind meo appendix - Printed publicationo 7 riddikter - Textartobject (included as part of the exhibition)To be made public in DiVA March 31st 2021o Centauring – The Book - Printed publicationo Moving through Choreography – Curating Choreography as an Artistic Practice - The dissertation's documented materials published in Research Catalogue

Astrometric and photometric observations of the comet 29P/Schwassmann-Wachmann 1 were performed at the Zeiss-1000 telescope of the International Astronomical Observatory Sanglokh (IAOS) of the Institute of Astrophysics, Academy of Sciences of the Republic of Tajikistan in July and August 2017. Although the comet has a short period of revolution it is regarded to be an object of the Centaurs group. Comet was exhibited a new activity this period which we used for analysis of its features. The coordinates of comet were determined and the orbit was calculated, the apparent and absolute magnitudes in BVRI bands were determined, as well the comet color indices and the estimation of nucleus diameter were obtained., 7 pages, 5 figures

This article examines, in its first part, the symbolic aspects of the relation between horses and men, and the mythical figure of the centaur, most often assimilated to virility and male sexual drive, but also to women and their sexuality. In its second and central part, it focuses on Bartabas and Ko Murobushi’s performance, The Centaur and the Animal (2012) while raising ethical issues relating to performing animals. The essay analyzes how this play deconstructs the opposition between masculinity and femininity, as well as between animal and human, among other oppositional pairs such as reason vs. instinct, activity vs. passivity, verticality vs. horizontality or “inclination,” immunity vs. vulnerability, life vs. death, animate vs. inanimate, among others. It posits that Bartabas’s performance opens the possibility of a posthuman and postanimal perspective on the relation between human and nonhuman animals.

We examine the dynamics of small bodies in orbits similar to that of comet 29P/Schwassmann-Wachmann 1, i.e. near-circular orbits between Jupiter and Saturn. As of late 2019, there are 14 other known bodies in this region that lie in similar orbits. Previous research has shown that this region of the solar system, which in this work we call the "near Centaur region" (NCR), is not stable, suggesting that any bodies found in it would have very short lifetimes. We performed 20 Myr high-precision numerical simulations of the evolution of massless particles, initially located in the Kuiper belt but close to Neptune, with perihelia slightly below 33 au ("Neptune crossers"). Some of these particles quickly migrate inward, passing through the NCR before becoming Jupiter Family Comets. We find that objects in the NCR do indeed generally travel through it very quickly. However, our simulations reveal that resonant behavior in this region is somewhat common and can trap objects for up to 100 Kyr. We summarize the dynamics of 29P and other observed bodies in the region---two of which seem to be clearly exhibiting resonant behavior---and use our simulations to put limits on the reservoir size of the Neptune crossers, which at its time determines the reservoir size of the Kuiper belt. Finally, we put some constraints on the current population of Centaurs and particularly of the NCR population, based on the injection rates required to keep the observed population of Jupiter family comets in steady-state., 15 pages, 11 figures

This chapter discusses reception of ancient Greek centaurs in Russian tales and apocrypha. From the end of the 13th century, a number of tales from the international repertoire of medieval stories have appeared in Russia in translations and adaptations. Among them the tales of King Solomon and the beast Kitovras (the Russian transliteration of the Greek Κένταυρος), folkloric apocrypha based on Biblical stories, were presented. These tales tell how King Solomon decided to build a temple in Jerusalem and needed the help of a “feet-footed beast”, a legendary centaur Kitovras. This half-man and half-beast, being a wizard and a prophet, appears as the king’s rival who is even wiser than Solomon himself. Besides, he possesses enormous physical strength, and he has a weakness for vine and women, which destroys him. From the end of the 16th century, medieval Italian and French adventure novels were translated into Russian from the German and Polish chapbooks versions. The Story of Prince Bova translated from Polish or Belarusian goes back through the Ragusa version to the Italian romance of Buovo d’Antona and finally to the Anglo-Norman Bevis of Hampton. This novel became extremely popular, and it acquired features of Russian folk tale depicted in numerous and cheap lubok prints. The main hero Prince Bova has an enemy Polkan, a half-human half-horse creature of enormous strength and speed, who, after the first battle with Bova, becomes his best friend and defender. De-etymologization of the Italian word Puli-cane (a half-dog) as a Polkan [Pol-kon’] creates a new hero whose name in Russian could mean a half-horse, and who looks like a centaur. Russian tales appear to fantastically reflect and contaminate too parallel traditions presenting centaurs since Antiquity: on the one hand, centaurs are savage, violent and destructive creatures; on the other hand, one of them, Chiron was the wise prophet and the educator of main ancient Greek heroes., The volume gathers the results of a stage of the programme Our Mythical Childhood, supported by an Alexander von Humboldt Foundation Alumni Award for Innovative Networking Initiatives and an ERC Consolidator Grant. Open Access at Universitätsverlag Winter GmbH at https://www.winter-verlag.de/en/detail/978-3-8253-7874-5/Marciniak_Ed_Chasing_Mythical_Beasts_PDF/ book/ hardcover ISBN: 978-3-8253-6995-8 Series: Studien zur europäischen Kinder- und Jugendliteratur/Studies in European Children's and Young Adult Literature, Volume No.: 8 Information about Our Mythical Childhood is available at http://omc.obta.al.uw.edu.pl/

In two recent papers published in MNRAS, Namouni and Morais (2018, 2020) claimed evidence for the interstellar origin of some small Solar System bodies, including i) objects in retrograde co-orbital motion with the giant planets, and ii) the highly-inclined Centaurs. Here, we discuss the flaws of those papers that invalidate the authors' conclusions. Numerical simulations backwards in time are not representative of the past evolution of real bodies. Instead, these simulations are only useful as a means to quantify the short dynamical lifetime of the considered bodies and the fast decay of their population. In light of this fast decay, if the observed bodies were the survivors of populations of objects captured from interstellar space in the early Solar System, these populations should have been implausibly large (e.g. about 10 times the current main asteroid belt population for the retrograde coorbital of Jupiter). More likely, the observed objects are just transient members of a population that is maintained in quasi-steady state by a continuous flux of objects from some parent reservoir in the distant Solar System. We identify in the Halley type comets and the Oort cloud the most likely sources of retrograde coorbitals and highly-inclined Centaurs., Comment: in press in MNRAS

Funded by the Robert Martin Ayers Sciences Fund and NSF AST-1412587. We observed the 2020 February 4th outburst of the Centaur 29P/Schwassmann-Wachmann, using the James Gregory Telescope in St Andrews/UK. The brightness of the comet increased by ∼3 mag in VRI within 1-2 days, followed by a more gradual incline. This was one of the largest documented outbursts of this object over the past few years, but is consistent with previously observed events. Postprint Non

29P/Schwassmann Wachmann is an unusual solar system object. Originally classified as a short-period comet, it is now known as a Centaur that recently transferred to its current orbit, and may become a Jupiter Family comet. It has exhibited a dust coma for over 90 years, and regularly undergoes significant dust outbursts. Carbon monoxide is routinely detected in high amounts and is typically assumed to play a large role in generating the quiescent dust coma and outbursts. To test this hypothesis, we completed two 3-month long observing campaigns of the CO J=2-1 rotational line using the Arizona Radio Observatory 10m Sub-millimeter Telescope during 2016 and 2018-2019, and compared the results to visible magnitudes obtained at the same time. As the Centaur approached its 2019 perihelion, the quiescent dust coma grew $\sim$45\% in brightness, while it is unclear whether the quiescent CO production rate also increased. A doubling of the CO production rate on 2016 Feb 28.6 UT did not trigger an outburst nor a rise in dust production for at least 10 days. Similarly, two dust outbursts occurred in 2018 while CO production continued at quiescent rates. Two other dust outbursts may show gas involvement. The data indicate that CO- and dust-outbursts are not always well-correlated. This may be explained if CO is not always substantially incorporated with the dust component in the nucleus, or if CO is primarily released through a porous material. Additionally, other minor volatiles or physical processes may help generate dust outbursts., Accepted for publication in The Astronomical Journal

In 1977, while Apple II and Atari computers were being sold, a tiny dot was observed in an inconvenient orbit. The minor body 1977 UB, to be named (2060) Chiron, with an orbit between Saturn and Uranus, became the first Centaur, a new class of minor bodies orbiting roughly between Jupiter and Neptune. The observed overabundance of short-period comets lead to the downfall of the Oort Cloud as exclusive source of comets and to the rise of the need for a Trans-Neptunian comet belt. Centaurs were rapidly seen as the transition phase between Kuiper Belt Objects (KBOs), also known as Trans-Neptunian Objects (TNOs) and the Jupiter-Family Comets (JFCs). Since then, a lot more has been discovered about Centaurs: they can have cometary activity and outbursts, satellites, and even rings. Over the past four decades since the discovery of the first Centaur, rotation periods, surface colors, reflectivity spectra and albedos have been measured and analyzed. However, despite such a large number of studies and complementary techniques, the Centaur population remains a mystery as they are in so many ways different from the TNOs and even more so from the JFCs. Facultad de Ciencias Astronómicas y Geofísicas Instituto de Astrofísica de La Plata

The outer Solar System contains a large number of small bodies (known as trans-Neptunian objects or TNOs) that exhibit diverse types of dynamical behavior. The classification of bodies in this distant region into dynamical classes -- sub-populations that experience similar orbital evolution -- aids in our understanding of the structure and formation of the Solar System. In this work, we propose an updated dynamical classification scheme for the outer Solar System. This approach includes the construction of a new (automated) method for identifying mean-motion resonances. We apply this algorithm to the current dataset of TNOs observed by the Dark Energy Survey (DES) and present a working classification for all of the DES TNOs detected to date. Our classification scheme yields 1 inner centaur, 19 outer centaurs, 21 scattering disk objects, 47 detached TNOs, 48 securely resonant objects, 7 resonant candidates, and 97 classical belt objects. Among the scattering and detached objects, we detect 8 TNOs with semi-major axes greater than 150 AU., accepted to AJ

The data obtained in the recent Rosetta space mission to comet 67P/Churyumov–Gerasimenko have had a profound impact on the understanding of the nature of comets. In addition to revising the notions on the physical properties and structure of comets, this addresses dynamical aspects of the formation of the observed cometary populations (short- and long-period comets, Centaurs, trans-Neptunian objects, and Oort-cloud objects). In the review, we discuss new problems that have appeared in the theory of dynamical evolution and origin of comets due to the Rosetta mission.

Meinong’s thought has been rediscovered in recent times by analytic philosophy: his object theory has significant consequences in formal ontology, and especially his account of impossible objects has proved itself to be decisive in a wide range of fields, from logic up to ontology of fiction. Rejecting the traditional ‘prejudice in favour of the real’, Meinong investigates what there is not: a peculiar non-existing object is precisely the fictional object, which exemplifies a number of properties (like Sherlock Holmes, who lives in Baker Street and is an outstanding detective) without existing in the same way as flesh-and-blood detectives do. Fictional objects are in some sense incomplete objects, whose core of constituent properties is not completely determined. Now, what does it imply to hold that a fictional object may also occur in true statements? We shall deal with the objections raised by Russell and Quine against Meinong’s view, pointing out limits and advantages of both perspectives.

Centaurs--icy bodies orbiting beyond Jupiter and interior to Neptune--are believed to be dynamically related to Jupiter Family Comets (JFCs), which have aphelia near Jupiter's orbit and perihelia in the inner Solar System. Previous dynamical simulations have recreated the Centaur/JFC conversion, but the mechanism behind that process remains poorly described. We have performed a numerical simulation of Centaur analogues that recreates this process, generating a dataset detailing over 2.6 million close planet/planetesimal interactions. We explore scenarios stored within that database and, from those, describe the mechanism by which Centaur objects are converted into JFCs. Because many JFCs have perihelia in the terrestrial planet region, and since Centaurs are constantly resupplied from the Scattered Disk and other reservoirs, the JFCs are an ever-present impact threat., Companion paper to "It's Complicated: A Big Data Approach to Exploring Planetesimal Evolution in the Presence of Jovian Planets" in The Astronomical Journal: https://doi.org/10.3847/1538-3881/aae095

Transneptunian objects (TNOs) are a source of invaluable information to access the history and evolution of the outer solar system. However, observing these faint objects is a difficult task. As a consequence, important properties such as size and albedo are known for only a small fraction of them. Now, with the results from deep sky surveys and the Gaia space mission, a new exciting era is within reach as accurate predictions of stellar occultations by numerous distant small solar system bodies become available. From them, diameters with kilometer accuracies can be determined. Albedos, in turn, can be obtained from diameters and absolute magnitudes. We use observations from the Dark Energy Survey (DES) from November 2012 until February 2016, amounting to 4292847 CCD frames. We searched them for all known small solar system bodies and recovered a total of 202 TNOs and Centaurs, 63 of which have been discovered by the DES collaboration until the date of this writing. Their positions were determined using the Gaia Data Release 2 as reference and their orbits were refined. Stellar occultations were then predicted using these refined orbits plus stellar positions from Gaia. These predictions are maintained, and updated, in a dedicated web service. The techniques developed here are also part of an ambitious preparation to use the data from the Large Synoptic Survey Telescope (LSST), that expects to obtain accurate positions and multifilter photometry for tens of thousands of TNOs., 25 pages, submitted to Astronomical Journal

Although immunoassays in measuring 25-hydroxyvitamin D [25(OH)D] have been improved recently, relatively large differences are still seen between results of 25(OH)D measured by immunoassays and by liquid chromatography-tandem mass spectrometry (LC-MS/MS). In the present studies, we compared two immunoassays with LC-MS/MS for measuring 25(OH)D concentrations. Concentrations of 25-hydroxyvitamin D2 [25(OH)D2] and 25-hydroxyvitamin D3 [25(OH)D3] in serum samples from 59 healthy subjects were measured by two immunoassays including Siemens ADVIA Centaur Vitamin D Total (Centaur) and Roche Elecsys Vitamin D Total (Elecsys) and LC-MS/MS. To determine the cross reactivity of Elecsys and Centaur toward 25(OH)D2, a dosage of 200,000 IU vitamin D2 was given after first sampling. Serum samples were obtained 30 days later and concentrations of 25(OH)D2 and 25(OH)D3 were measured again. The results showed poor agreement between the immunoassays and LC-MS/MS in 25(OH)D2 and 25(OH)D3 measurements. The percentage of 25(OH)D2 cross-reactivity was 45.3% for Centaur and 41.2% for Elecsys and there was no significant difference between Centaur and Elecsys. In conclusion, Centaur and Elecsys perform unsatisfactorily in measuring 25(OH)D levels, especially for 25(OH)D2 cross-reactivity. Therefore, clinicians need to be aware of the underestimation of vitamin D status when using these immunoassays for measuring individuals supplemented with vitamin D2.

Centaurs have orbits between Jupiter and Neptune and are thought to originate from the trans-Neptunian region. Observations of surface properties of Centaurs and comparison with those of trans-Neptunian objects (TNOs) would provide constraints on their origin and evolution. We analyzed imaging data of nine known Centaurs observed by the Hyper Suprime-Cam (HSC) installed on the Subaru Telescope with the g and i band filters. Using the data available in the public HSC data archive as well as those obtained by the HSC Subaru Strategic Program (HSC-SSP) by the end of June, 2017, we obtained the g-i colors of the nine Centaurs. We compared them with those of known TNOs in the HSC-SSP data obtained by Terai et al. (2018). We found that the color distribution of the nine Centaurs is similar to that of those TNOs with high orbital inclinations, but distinct from those TNOs with low orbital inclinations. We also examined correlations between the colors of these Centaurs and their orbital elements and absolute magnitude. The Centaurs' colors show a moderate positive correlation with semi-major axis, while no significant correlations between the color and other orbital elements or absolute magnitude were found for these Centaurs. On the other hand, recent studies on Centaurs with larger samples show interesting correlations between their color and absolute magnitude or orbital inclination. We discuss how our data fit in these previous studies, and also discuss implications of these results for their origin and evolution., 12 pages, 4 figures. Accepted for publication in Publications of the Astronomical Society of Japan