Optical (emission lines and continuum) versus radio emission of the Teacup galaxy. Left panel: false-colour image from VLT/MUSE. [O III] ionised gas emission is reported in green, Hα in red, and line-free continuum emission averaged between 5500–6700 Å (observed wavelengths) in blue. The colour intensity scale is the same for [O III] and Hα. The main spatial features mentioned in the text are labelled. Right panel: 20″ × 20″ zoomed-in [O III] emission (same as in left panel), with the contours of the VLA 5.12 GHz (white) and highest-resolution 6.22 GHz (magenta) radio images from Harrison et al. (2015) overlaid. For the former, contour levels are 35.0, 66.0, 124, and 234 μJy beam⁻¹; for the latter, they are 40, 102, 261, and 668 μJy beam⁻¹. The black numbered “+” symbols mark the regions from which the spectra reported in Fig. 2 were extracted.