In Memory of Dr. Erling Nielsen

Dr. Erling Nielsen, former scientist at the Max Planck Institute for Solar System Research (formerly: Max Planck Institute for Aeronomy) passed away on March 6 this year after a long illness. For more than 31 years, Dr. Nielsen helped shape the research at the institute.

Dr. Nielsen studied electrical engineering and solid state physics at the Technical University of Denmark. Already in his doctoral studies at the former Bartol Research Foundation in the US state of Pennsylvania, which he completed in 1975, he turned to space research and investigated how solar cosmic rays propagate in interplanetary space and in the magnetosphere.

At the Max Planck Institute for Aeronomy in Katlenburg-Lindau, his research focused primarily on the Earth's ionosphere. Dr. Nielsen was a driving force in the construction and operation of the RIO imager (Relative Ionospheric Opacity imager) in northern Norway, a measurement facility that determined the absorptivity of the ionosphere in the frequency range of radio waves with previously unattained accuracy, and was a significant part of the STARE project (Scandinavian Twin Auroral Radar Experiment). In later years, he also contributed to the development and construction of scientific instruments for space missions, such as the MARSIS radar altimeter for ESA’s Mars Express mission and the CONSERT radio wave experiment for ESA’s Rosetta mission.

After his retirement in 2005, Dr. Nielsen continued to participate in the developments at the institute - even after the institute moved to Göttingen. His extensive expertise, his conscientious scientific approach, and his quiet and friendly manner will be fondly remembered.

With Dr. Erling Nielsen, the institute loses a valued and excellent scientist and a long-time friend.