Claus Leitherer currently serves as the President of IAU Division J, Galaxies and Cosmology.

Division J covers all areas dealing with the physics of the universe, and the physics of galaxies composing it, excluding the Milky Way, which is relevant to Division H ("Interstellar Matter and Local Universe"). Also, some of the topics are shared with Division D ("High Energy Phenomena and Fundamental Physics").

The main topics can be categorized as follows:

  • Physics and content of the Universe
    The early Universe, cosmological models;
    Baryonic and non-baryonic matter, dark matter and dark energy.
  • Evolution of structures
    Cosmic backgrounds (CMB, and all backgrounds from radio to gamma-rays);
    Populations of galaxies, galaxy clusters and groups, intergalactic medium.
  • Formation and evolution of galaxies
    Reionization, first objects (AGN, Starbursts), history of star formation;
    Physics of galaxies at all redshifts, role of the environment.
  • Spatially resolved galaxies
    Star formation laws in galaxies, resolved stellar population;
    Dynamics of sub-structures (bulges, disks, spiral structure...).

Send email to Claus Leitherer for all inquiries regarding membership, conferences, scientific matters relevant to the IAU, or other issues.