Compilation of first moment maps (intensity-weighted peak velocities) toward M17 of the THOR RRL data (left panel) with ionized carbon, atomic carbon, and molecular carbon (second to fourth panels) taken from Pérez-Beaupuits et al. (2012, 2015). The color scale for the recombination lines is from 0 to 27 km s^-1, for the others from 11 to 27 km s^-1. The contours show the 870 μm continuum data from the ATLASGAL survey starting at a 4σ level of 200 mJy beam^-1.