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The origin of cometary volatiles remains a major open question in planetary science. Comets may have either agglomerated from crystalline ices condensed in the protosolar nebula (PSN) or from amorphous ice originating from the molecular cloud and interstellar medium. Here, based on the recent argon, krypton, and xenon measurements performed by the ROSINA mass spectrometer on board the European Spa

Radiolytic production has been proposed as a potential source for the molecular oxygen observed in comet 67P/Churyumov-Gerasimenko. Radiolysis can be exogenic or endogenic, the latter due to radionuclides present in the dust constitutive of the comet nucleus. We investigated the possibility of forming a significant amount of molecular oxygen through endogenic radiolysis. We applied a model of radi

The four massive Galilean satellites are believed to have formed within a circumplanetary disk during the last stages of Jupiter's formation. While the existence of a circum-Jovian disk is supported by hydrodynamic simulations, no consensus exists regarding the origin and delivery mechanisms of the building blocks of the forming satellites. The opening of a gap in the circumsolar disk would have e

Molecular oxygen has been detected in the coma of comet 67P/Churyumov-Gerasimenko with a mean abundance of 3.80 ±0.85% by the ROSINA mass spectrometer on board the Rosetta spacecraft. To account for the presence of this species in comet 67P/Churyumov-Gerasimenko, it has been shown that the radiolysis of ice grain precursors of comets is a viable mechanism in low-density environments, such as molec

Writing is a central activity at university. Writing in English at University: A Guide for Second Language Writers is a textbook designed to accompany the MOOC Writing in English at University. It can also be used as a stand-alone handbook, with links to online resources, such as instructional videos on key aspects of academic writing provided throughout.Just like the MOOC, this textbook targets u

The ice giants Uranus and Neptune are the least understood class of planets in our solar system but the most frequently observed type of exoplanets. Presumed to have a small rocky core, a deep interior comprising ∼70% heavy elements surrounded by a more dilute outer envelope of H 2 and He, Uranus and Neptune are fundamentally different from the better-explored gas giants Jupiter and Saturn. Becau

Despite the fact that the observed gradient in water content among the Galilean satellites is globally consistent with a formation in a circum-Jovian disk on both sides of the snowline, the mechanisms that led to a low water mass fraction in Europa (∼8%) are not yet understood. Here, we present new modeling results of solids transport in the circum-Jovian disk accounting for aerodynamic drag, turb

S2 has been observed for decades in comets, including comet 67P/Churyumov-Gerasimenko. Despite the fact that this molecule appears ubiquitous in these bodies, the nature of its source remains unknown. In this study, we assume that S2 is formed by irradiation (photolysis and/or radiolysis) of S-bearing molecules embedded in the icy grain precursors of comets and that the cosmic ray flux simultaneou

The origin of Phobos and Deimos is still an open question. Currently, none of the three proposed scenarios for their origin (intact capture of two distinct outer solar system small bodies, co-accretion with Mars, and accretion within an impact-generated disk) are able to reconcile their orbital and physical properties. Here we investigate the expected mineralogical composition and size of the grai

Molecular oxygen has been detected in the coma of comet 67P/Churyumov-Gerasimenko with abundances in the 1%-10% range by the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis-Double Focusing Mass Spectrometer instrument on board the Rosetta spacecraft. Here we find that the radiolysis of icy grains in low-density environments such as the presolar cloud may induce the production of large a

In The Ethics of The Tripartite Tractate (NHC I, 5) Paul Linjamaa offers the first full length thematical monograph on the longest Valentinian text extant today. By investigating the ethics of The Tripartite Tractate, this study offers in-depth exploration of the text's ontology, epistemology, theory of will, and passions, as well as the anthropology and social setting of the text. Valentinians ha

Vi reser ut från planeten Jorden, förbi Månen och planeterna i vårt solsystem, ut bland stjärnorna. Vi får reda på hur långt ut vi har, än så länge, skickad våra astronomer och våra rymdsonder. Vi får reda på hur litet det avståndet är jämfört med avståndet som sträcker sig mellan avlägsna stjärnor. Vi reser vidare och observerar hela vår galax, Vintergatan, Vi observerar hur det dvärggalaxer och We leave planet Earth and fly past the Moon and the planets in our Solar System. Out among the stars. We observe how far our astronauts and space probes have traveled, so far, and we discover how that distance compares to the enormous distances between the stars surrounding us.We go further and get to see our entire galaxy, the Milky Way. We observe how dwarf galaxies and globular clusters orbit o

Wind damage to forests can be divided into (1) the direct damage done to the forest and (2) indirect effects. Indirect effects may be of different kinds and may affect the environ- ment as well as society. For example, falling trees can lead to power and telecommunica- tion failures or blocking of roads. The salvage harvest of fallen trees is another example and one that involves extremely dangero

Cultural relict plants are remaining populations of plants once introduced for cultivation and use. The plants have survived, even though the population is no longer actively maintained. Cultural relict plants can be found in the close surround- ings of historical places such as monastery ruins, churches, castles, fortresses, manors, old farms and villages. The plants are part of a living heritage

Boken ger grundläggande kunskape om samhällsekonomiska företeelser som påverkar socialpolitikens förutsättningar och finansieringen av välfärdsstaten, liksom det praktiska arbetet och människors möjligheter till försörjning. Den vänder sig primärt till socionomstudenter och verksamma inom socialt arbete, men även till studenter inom närliggande ämnen på universitet, högskolor och folkhögskolor.

Nationally Red-listed bryophytes in the county of Skåne, southern-most Sweden] The status and present as well as past distribution of the 85 bryophyte taxa that have been reported from the county are described and briefly summarised and localities with revcent recerds of several Red-listed species are listed, mapped and described. The number of Red-listed species per 5x5 km grid-square, and all kn

This article analyses the three recent Nordic Noir television series Bordertown (Sorjonen) from Finland, Trapped (Ófæro), from Iceland, and the Danish- Swedish The Bridge (Broen/Bron). All series are located on national borderlands, and this article aims to discern the significance of using such borderland settings. Departing from Doreen Massey's emphasis on places as being inherently interlinked