Identification of the radio emission observed stereoscopically by STEREO/WAVES. Panel a) shows the solar type III radio burst observed simultaneously (dt ≈ 0) by STEREO-A (STA) and STEREO-B (STB). Panels b) and c) display examples of the DAM emission. The radiation on panel b) was observed sequentially by both spacecraft with time delay (dt ≈ 0.71 h) which corresponds to ≈ 26° of Jupiter’s rotation and ≈ 6.0° of the Io angular shift along its orbit. Since the angular separation between both spacecraft as seen from Jupiter was ≈ 6.3° we conclude that the observed radio emission is Io related DAM (see Sect. 2). Panel c) illustrates the identification of non-Io DAM. The spectra in b) and c) are plotted with a correction for difference in light travel time from Jupiter to each of the spacecraft.