One Air Sciences’ team member’s graduate research at Portland State University (Oregon) clocked a lot of time with a tabletop ultraviolet (UV)-visible spectrometer. This equipment measures how much a chemical substance absorbs light. You see, Matt had painstakingly prepared hundreds of passive air pollution monitoring devices to conduct high-density measurements of nitrogen dioxide (NO2) in east Portland. To “extract” the adsorbed NO2 from the devices, an aqueous solution was prepared with spectral properties that changed with the amount of NO2 present. Perfect, tedious work for a grad student, but it ultimately produced some gratifying results.