Radio source positions obtained using DF data in the 3D space (colorful spheres in blue to violet shades). The yellow and green sphere represent the Sun and PSP, respectively. The sizes of radio sources, Sun and PSP are not relative to each other. Panel (a) displays the radio source positions for the first type III bursts shown in the dynamic spectra (Fig. 3). The radio source positions show the propagation path of the type III radio burst in the southward direction from the ecliptic plane. Panel (b) presents estimated radio source positions (obtained with radio triangulation) for the second type III burst observed at ∼17:15 UT in STEREO-A and Wind. The radio source positions show the propagation path of the type III radio burst more in the equatorial plane than in the case of the first type III.