Understanding and predicting the absorption and emission properties of interstellar dust grains is essential in many areas of astrophysics, but a large number of grain properties such as their place of birth, structure, composition, response to the environment are still debated. Fortunately, we have entered a period of new developments, thanks to recent space missions and new-generation ground-based spectrographs. I will focus on the progress made possible by data from the ESA’s Gaia mission. For the first time, large-scale three-dimensional maps of galactic dust clouds have been calculated by synthesising measurements of the reddening of starlight for a large number of individual stars. The results are very different from existing schematic representations. On the other hand, the so-called extinction curve, i.e. the dependence of dust absorption on wavelength, is the subject of new developments that are yielding unexpected results. I will present ongoing attempts to link the shape and level of this curve to other measurable interstellar quantities.
Extinction by Galactic dust : where and how ?
Lundi 2 février 2026
de
11:00 à
12:00
Amphithéâtre, bâtiment 18 Evry Schatzman - Campus de Meudon, Observatoire de Paris-PSL
