A dummy simulating a breathing human being sits in the NDR's Great Broadcasting Hall before the start of a concert by the NDR Radiophilharmonie, in Hanover, Germany, Thursday, June 10, 2021. The concert serves as an experiment on the distribution of aerosols in space. Dummies from the Fraunhofer Heinrich Hertz Institute are in the hall to precisely measure the distribution of aerosols. (Moritz Frankenberg/dpa via AP)