a: heliocentric radial velocities for our investigated region. Blue: a single radial velocity measurement and the associated uncertainty for Hα, observed with the Southern African Large Telescope (SALT). Red: temperature vs. radial velocity for H I gas within the investigated region, observed with the Australia Telescope Compact Array (ATCA). Black: histogram of stellar radial velocities from Ramachandran et al. (2019), covering a population of ∼100 photometered stars, or ∼10% of the photometered population. b: MCELS narrow-band Hα image of the SMC Wing highlighting the supergiant shell SMC-SGS 1. Points indicate the locations of stars among the combined photometric and spectroscopic sample, with marker color representing radial velocity and marker size representing difference from the stellar median radial velocity of 170 km s⁻¹.