Top left : three colour image of G34.77. Red is 24 μm emission from the MIPSGAL survey (Carey et al. 2009), green is 8 μm emission from the GLIMPSE survey (Churchwell et al. 2009), and blue is 1 GHz continuum emission from the THOR survey (Beuther et al. 2016). Top right : mass surface density map (colour scale; Kainulainen & Tan 2013) with the red circle indicating the location of the Clump. Bottom panels : zoom-in views of the Clump at 2 μm (2MASS; Skrutskie et al. 2006), 8 μm (Carey et al. 2009), 24 μm (Churchwell et al. 2009), and 70 μm (Hi-GAL Molinari et al. 2010) emission. The cyan contours correspond to a mass surface density value of 0.3 g cm⁻². In all panels, the magenta contour corresponds to a mass surface density of 0.1 g cm⁻² and highlights the cloud outskirts. The red circle size corresponds to 44″, i.e. the largest beam size in the Yebes-40m observations.