Professor Matthias Hullin from the University of Bonn. (image) University of Bonn Share Print E-Mail Caption The background shows an optical echo simulated with methods developed in Bonn. Credit © Photo: Volker Lannert/Uni Bonn Usage Restrictions This photo may be used with the press release. Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.