Microwave absorptivity by sulfuric acid in the Venus atmosphere: First results from the Venus Express Radio Science experiment VeRa

► 3.6 cm Radio absorption in the Venus atmosphere between 2006 and 2011 is studied. ► A distinct latitudinal variation in the southern hemisphere is observed. ► The abundance of sulfuric acid vapor between 50 and 55 km has been derived. ► Increased abundances are observed at low latitudes on the dayside and nightside.