Left panels: ALMA HNC (J = 4−3) spectra observed at Titan’s eastern and western limbs in 2016 August and 2017 May, rebinned to a common channel spacing of 202 m s⁻¹. Fitted Gaussian profiles are overlaid (dotted curves), along with their central velocities (vertical dotted lines). Right panels: corresponding continuum-subtracted, spectrally integrated flux maps of Titan’s HNC (J = 4−3) emission. The eastern and western spectra in the left panels were extracted 600 km above the equator, at the points labeled E and W, respectively. The FWHM of the (Gaussian) spatial resolution element is shown in the lower left of each map. Sky-projected distances are given with respect to the center of Titan’s disk (the ordinate axis is aligned with celestial north).