le 1 septembre 2023, 11h à 13h, Arturo Lopez, salle Jules Verne, OMP, site Belin Resumé: The phase of a wave can only be defined unambiguously for complex waves. This strange quantity appears at the core of all physics: from the quantification of atomic levels or of the electric charge to the source of the electromagnetic […]
le 28 octobre 2022, 11h à 13h, Sylvie Vauclair, salle Jules Verne, OMP, site Belin The formation and evolution of planetary systems are important subjects. But what about their ultimate fate, when their host stars evolve as red giants, lose their gaseous envelopes as planetary nebulae, and end their lives as white dwarf stars? Recent […]
le 9 décembre 2022, 11h à 13h, Roberta Amato, salle Jules Verne, OMP, site Belin Ultraluminous X-ray sources (ULXs) are amongst the brightest extra-galactic objects in the X-ray sky. They are characterized by luminosities well above the Eddington limit, the maximum possible luminosity reached when the radiation pressure and the gravitational force are in equilibrium. […]
le 16 décembre 2022, 11h à 13h, Florian Debras, salle Jules Verne, OMP, site Belin With more than 5000 exoplanets discovered, we have access to numerous statistics which represent the condition of formation and evolution of planetary systems. One of such statistics is the eccentricity distribution of warm Jupiters: planets around the mass of Jupiter, […]
le 2 décembre 2022, 11h à 13h, Guillaume Loizelet, salle Jules Verne, OMP, site Belin In this session, I will review the results obtained by historians of astronomy over the last fifty years, which have led to a complete rethinking of the idea of a scientific revolution developed in the mid-twentieth century.I will first look […]
le 25 novembre 2022, 11h à 13h, Guillaume Loizelet, salle Jules Verne, OMP, site Belin Using the available databases, it was possible for ancient « astronomers » to propose models to account for observable celestial movements. The climax of these attempts is undoubtedly the great mathematical synthesis (known as the Almagest) written in Greek by the Alexandrian […]
le 18 novembre 2022, 11h à 13h, Guillaume Loizelet, salle Jules Verne, OMP, site Belin It is not possible to develop a mathematical model without a reliable and consistent database.In this session, I will first detail the cultural context that led the Babylonian « astronomers » to establish formidable data collections in the form of clay tablets. […]
le 14 octobre 2022, 11h à 13h, Olivier Berné, salle Jules Verne, OMP, site Belin In this seminar, I will present the first scientific results that have been obtained from the JWST mission. After a general presentation of the mission and science results on various topics, I will describe the Early Release Science (ERS) project […]
le 21 octobre 2022, 11h à 13h, Nicolas Clerc, salle Jules Verne, OMP, site Belin Observations of galaxy clusters at X-ray wavelengths offer a unique window to understanding the physical processes governing the assembly of large-scale structure in our Universe and the cosmic web. X-rays signpost the hot and tenuous gas that permeates the entire […]