Simultaneous images taken at 15:36 UT on May 17, 2011, from SDO_AIA and Stereo_A-EUVI. Top left panel: composite image of 12 visible trajectories of falling plasma with white dotted lines, from SDO_AIA. Top right frame: area of prominence tube with a red dashed line in 195 Å wavelength from Stereo_A-EUVI spacecraft. Bottom image: space-time diagram of falling plasma obtained from a typical cut along the traced path (the white arrows indicate the starting point and the position of the cut “6” trajectory in the top left panel).