Professor of Planetary Astronomy, California Institute of Technology

Institute for Geophysics, Jackson School of Geosciences, University of Texas at Austin

Professor für Makrosoziologie, Otto-von-Guericke-Universität Magdeburg

HERTIE-School of Governane

Southwest Research Institute

JPL

Associate Professor (Research), Brown University

Heliophysics Division Director, NASA

Universidad de Valladolid

JPL / NASA / California Institute of Technology