Discovery of starspots on Vega. First spectrocopic detection of surface structures on a normal A-type star Torsten Bohm

Séminaire

6 janvier 2017

le 06 jan 2017 de11h00à 13h002017/01/06 2017/01/06

Discovery of starspots on Vega. First spectrocopic detection of surface structures on a normal A-type star

The results of an in depth analysis of a data set consisting of 7000 high resolution spectra of Vega is presented. Standard A-type stars have extended radiative zones and should therefore not show any signatures of surface structures linked to magnetic activity. Surprisingly enough, such surface structures have unambiguously been discovered on Vega.

Plus d'actualités

The first astronomical databases (700 BC – 100 BC): Babylonian systems and Hipparcus’ works

le 15 novembre 2023, 10h45 à 12h45, Guillaume Loizelet, salle Jules Verne, OMP, site Belin Resumé: 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. […]

A peculiar density profile inside Jupiter

le 6 décembre 2024, 10h45 à 12h45, Florian Debras, salle Jules Verne, OMP, site Belin Resumé: Since 2016, the Juno satellite is orbiting Jupiter and has completely changed our understanding of the planet. From the atmosphere to the deep interior, including the auroras, Juno is providing a wealth of data that challenges models of Jupiter. […]

A step by step rupture (Vth century AD – XVth century AD)

le 22 novembre 2024, 10h45 à 12h45, Guillaume Loizelet, salle Jules Verne, OMP, site Belin Resumé: 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 […]

Rechercher