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Measured Fluxes of nitrous acid at Browning Pass, Antarctica were very low, despite conditions that are generally understood as favorable for HONO emissions, including: acidic snow surfaces, an abundance of NO₃^- anions in the snow surface, and abundant UV light for NO₃^- photolysis. Photochemical modeling suggests noon time HONO fluxes of 5–10 nmol m^-2 h^-1; the measured fluxes, however, were close to zero throughout the campaign. The location and state of NO₃^- in snow is crucial to its reactivity. The analysis of soluble mineral ions in snow reveals that the NO₃^- ion is probably present in aged snows as NaNO₃. This is peculiar to our study site, and we suggest that this may affect the photochemical reactivity of NO₃^-, by preventing the release of products, or providing a reactive medium for newly formed HONO. In fresh snow, the NO₃^- ion is probably present as dissolved or adsorbed HNO₃ and yet, no HONO emissions were observed. We speculate that HONO formation from NO₃^- photolysis may involve electron transfer reactions of NO₂ from photosensitized organics and that fresh snows at our site had insufficient concentrations of adequate organic compounds to favor this reaction.