[1] The mantle plume model has been invoked to explain the formation of large igneous provinces (LIP) and associated age-progressive hotspot tracks. The shape of mantle plumes should be significantly altered by physical properties of the mantle and will influence how plume theory is used to interpret observational constraints. Based on theoretical analysis and numerical modeling, we explore the...

We present new kinematic results for a sample of 387 stars located in and around the Milky Way satellite dwarf spheroidal galaxy Leo I. These spectra were obtained with the Hectochelle multi-object echelle spectrograph on the MMT, and cover the MgI/Mgb lines at about 5200Å. Based on 297 repeat measurements of 108 stars, we estimate the mean velocity error (1σ) of our sample to be 2.4 km/s, with...

Introduction: We have studied a terraced fan deposit centered at 15.0° S, 299.7° E within one of the troughs of Coprates Catena in order to investigate the role that water may have played in its formation. Only a handful of these unique terraced fan deposits have been identified on Mars [1-4], although their small sizes make them difficult to identify with the current data sets. The few fan dep...

De nombreuses entreprises utilisent des logiciels libres dans leurs propositions commerciales. Il existe de études cas sur leur modèle d’affaires. Cependant, il manque une analyse globale synthétisant et structurant les différents modèles open-sources. En nous appuyant le cadre économiques la littérature en systèmes d’information, partons beso...

“Epur si muove” said Galileo Galilei when claiming that the Earth is rotating. Due to rotation, the equatorial radius of the Earth is about 21.4 km longer than its polar radius, so that the Mississippi from its source to the Gulf of Mexico is “raising” away from the Earth center. Of course, in terms of the equipotentials it is “descending” to the sea. The same can also be said about the stars, ...

In this paper, optimum trajectories in Earth Transfer Orbit (ETO) for a lunar transportation system are proposed. This paper aims at improving the payload ratio of the reusable orbital transfer vehicle (OTV), which transports the payload from Low Earth Orbit (LEO) to Lunar Low Orbit (LLO) and returns to LEO. In ETO, we discuss ballistic flight using chemical propulsion, multi-impulse flight usi...

The occultation of background stellar sources by foreground Kuiper Belt Objects (KBOs) can be used to survey physical properties of the KBO population. We discuss statistics related to a KBO occultation survey, such as the event duration distribution, and suggest that occultation searches can be effectively used to probe the KBO size distribution below 10 km. In particular, we suggest that occu...

Dans cet article nous interrogeons une difficulté profonde de la littérature économique portant sur les questions du conflit et révolution. Le en général révolution particulier ne sont pas nécessairement négatifs ou le « côté obscur l’intérêt personnel » mauvaises choses. Ils peuvent être source d&#8...

Selon les résultats de l’enquête du Programme International pour le Suivi des Acquis élèves (PISA) 2018, un élève 15 ans sur quatre est considéré comme lecteur peu performant. La génération d’inférences joue rôle majeur parmi processus compréhension en lecture et représente une source potentielle difficult&#2...