Résumé / Abstract Seminaire_GReCO

"Impact de la Relativité Générale en Astronomie Fondamentale de haute précision"

C. Le Poncin-Lafitte
Dept. Systèmes de Référence Temps Espace (SYRTE), Obs. Paris-Meudon-Nancay (Paris, France)

The interplay between modern fundamental astronomy and gravitational physics is very important for the progress in both these fields. Below some threshold of accuracy, Newtonian physics fails to describe observational data and the Einstein''s relativity theory must be used to model the data adequately. Many high-accuracy astronomical techniques have already passed this threshold. Moreover, modern astronomical observations cannot be adequately modelled if relativistic effects are considered as small corrections to Newtonian models. The whole way of thinking must be made compatible with General Relativity: this starts with the concepts of time, space and reference systems. On the other hand, high-accuracy astronomical observations play important role for gravitational physics itself, providing the latter with crucial observational tests.
An overview of relativistic reference systems, recommended by the International Astronomical Union, will first be presented. Then we will focus on how to use them through several examples, in particular construction of planetary (or natural satellites) ephemerides, spacecraft''s orbit determination and the relativistic models needed to the ongoing space astrometry mission Gaia.

lundi 9 mai 2011 - 11:00
Salle des séminaires Évry Schatzman,
Institut d'Astrophysique de Paris

Page web du séminaire / Seminar's webpage