Pierre Auger Observatory Fluorescence Detector

Scientists from the Institute for Astroparticle Physics of the Karlsruhe Institute of Technology in Germany and the National Institute for Nuclear Physics in Italy who study cosmic rays from outer space using information from the Pierre Auger Observatory in Argentina, noticed an unexpected reoccurring signal in their data. Together with scientists from the Institute of Atmospheric Physics of the German Aerospace Center, they figured out that the observatory was detecting a signal emitted by ESA’s Aeolus wind mission. The observatory is used to study the origin of ultrahigh-energy cosmic rays. Wide-field optical telescopes detect fluorescence radiation emitted from nitrogen molecules excited as cosmic-ray-induced particle cascades. The strongest fluorescence lines are in the ultraviolet, close to the 355 nm frequency of the Aeolus laser. The scientists plan to use this laser beam from space for systematic studies of the density of aerosols above the observatory and for the calibration of their telescopes.

Read full story: Aeolus paves the way for future wind lidars in space