438 μm continuum image of G351.77-0.54. The left panel shows a larger area encompassing the two central sources, as well as two additional submm sources in the southeast and northwest (all marked). The white crosses mark the cm continuum sources by Zapata et al. (2008). The right panel then shows a zoom into the center; the triangles present the class II CH₃OH masers from Walsh et al. (1998). The contour levels start at 4σ and continue in 2σ steps with the 1σ level of 7 mJy beam^-1. The synthesized beam of 0.06′′ and a scale-bar for an assumed distance of 2.2 kpc are presented as well.