Grand événement - Musique ! La Philharmonie au Collège de France

Cycle de rencontres en partenariat avec la Cité de la musique – Philharmonie de Paris

Collège de France

Année 2025-2026

Scènes et sources de la musique

Table ronde avec Pascal Dusapin, compositeur ; Netia Jones, metteuse en scène, scénographe et artiste vidéo, et Carlo Ossola, professeur émérite du Collège de France, titulaire de la chaire Littératures modernes de l'Europe néolatine.

Modératrice : Chloë Cambreling.

Résumé

Depuis quelques années, la Philharmonie produit ses propres spectacles. Il ne s'agit pas de la transformer en opéra ou en théâtre, mais d'imaginer, en dialogue avec des artistes, de nouvelles formes d'expression autour de la musique pour une salle de concert. C'est dans cet esprit que Netia Jones met en scène à l'automne 2025 à la Philharmonie la création d'Antigone, de Pascal Dusapin. Les échanges et collaborations de longue date entre Pascal Dusapin et Carlo Ossola, notamment autour du Il Viaggio, Dante, prolongeront cette table ronde en puisant dans les sources littéraires ou mythologiques de la musique, la plaçant encore davantage au carrefour de plusieurs formes d'expression.

Alessandro Morbidelli

Chaire Chaire Formation planétaire : de la Terre aux exoplanètes

Collège de France

Année 2025-2026

David Nesvorný

Conférence - David Nesvorný : Dynamical Origins and Properties of the Near-Earth Object Population

David Nesvorný

Southwest Research Institute, USA

Résumé

Near-Earth Objects (NEOs) are a transient population of small bodies with orbits in or near the terrestrial planet region. They represent an intermediate stage in the dynamical evolution of asteroids and comets - originating in the main belt or trans-Neptunian scattered disk - and ending with planetary impacts, solar disintegration, or ejection from the Solar System. We present an accurate physical model of NEOs developed by tracking the dynamical evolution of main-belt asteroids and comets onto NEO orbits. The model is calibrated using data from the Catalina Sky Survey (CSS) and Wide-field Infrared Survey Explorer (WISE). Results show a size-dependent contribution from the main belt, with the ν6 and 3:1 resonances accounting for ~80% of faint NEOs. The debiased NEO albedo distribution is well fit by a sum of two Rayleigh distributions with scale parameters of 3% and 17%. We estimate 830±60 NEOs with diameters >1 km and 20,000±2,000 with diameters >140 m. The Earth impact probability for a >140 m object over the next millennium is ~5%. Compared to a direct-delivery model from the main belt, the CSS-detected small NEOs show an excess of low-eccentricity orbits between 1–1.6 au. This excess may result from tidal disruption of large NEOs during close encounters with the Earth.

Alessandro Morbidelli

Chaire Chaire Formation planétaire : de la Terre aux exoplanètes

Collège de France

Année 2025-2026

David Nesvorný

Conférence - David Nesvorný : Collisional Families in the Asteroid Belt and Sources of Meteorites

David Nesvorný

Southwest Research Institute, USA

Résumé

Main-belt asteroids originally formed in a dynamically quiet disk, but their orbits were later stirred by Jupiter's gravity, leading to high-speed collisions. Over the age of the Solar System, dozens of large asteroids have been disrupted by such impacts, producing groups of fragments known as asteroid families. Here we explain how asteroid families are identified, review the current inventory, and discuss how they provide insight into the collisional and dynamical evolution of the asteroid belt. Currently, about 360 asteroid families have been cataloged, including ~100 that formed within the past 10 million years. Studies of these families shed light on the physics of large-scale collisions - a key process in the formation of Earth and other terrestrial planets - and place important constraints on the belt's collisional history. Some findings suggest that much of the asteroid belt may be composed of fragments from early, unresolved breakups. Asteroid families also play a crucial role in understanding orbital evolution, including the influence of radiative forces like the Yarkovsky and YORP effects, as well as resonant interactions - processes that underpin the delivery of near-Earth asteroids and meteorites.