Radiometer Finds Sources of Fire (IMAGE) Fraunhofer-Gesellschaft Caption Test flight: Mounted on an airship belonging to the FernUniversität Hagen, the radiometer can detect the sources of fire even in low visibility. Credit Wolfgang Krüll Usage Restrictions The picture may be used for editorial purposes only. It is protected by copyright. The use is free of charge if the reference is mentioned. License Licensed content 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.