Measuring distances in astrophysics

le 12 septembre 2025, 10h45 à 12h45, Katia Ferrière, salle Jules Verne, OMP, site Belin

Summary: I will take you on a cosmic journey from the Earth to the far reaches of the observable Universe. We will first spend some time in the solar system, where I will show how the radius of the Earth and the distances to the Moon, the Sun and the other planets were historically measured. We will then leave the heliosphere and enter the interstellar medium of our Galaxy, where I will explain how the distances to other stars and to interstellar clouds can be measured. Finally, we will set off to explore other galaxies, galaxy clusters and superclusters, and we will see how the distances to these increasingly more remote objects can be measured.

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