Emission inside the dotted circle is the 218 GHz methyl formate doublet integrated in velocity (blue: 90−97 km s⁻¹, red: 97−104 km s⁻¹) towards core #2. The emission outside is the SiO (blue: 82−88 km s⁻¹, red: 108⁻119 km s⁻¹). Contours are 50% and 80% of maximum. The black ellipse is the methyl formate 0.28″ × 0.20″ beam. The black cross marks the centre of the continuum core and the red and blue crosses the maximum of the methyl formate emission.