This award to SRI International (Dr. Konstantinos Kalogerakis) will support the quantitative reevaluation of the mesosphere and lower thermosphere chemistry based upon new laboratory results. Nightglow emission signatures observed from space and ground-based instruments are commonly used as proxies for atmospheric composition, especially for the altitude region around 100 km that cannot be easily studied in situ. Monitoring the intensity and temporal evolution of such proxies by remote sensing is the method of choice to study many phenomena occurring in this region of the atmosphere. This award would support the quantitative reanalysis of the details relevant to the production and loss of excited atomic and molecular precursors responsible for prominent nightglow emissions. These results would quantify more precisely the study of atmospheric composition, radiative and energy balance, wave propagation and dissipation, as well as transport dynamics. One or two undergraduate students would be engaged in this work through a site REU grant awarded to SRI International.<br/><br/>The thrust of this reevaluation to be supported by this award would be aimed at the investigation of the coupling between the OH Meinel and the O2 Atmospheric band emissions, which is connected to the collisions of O atoms with vibrationally excited OH. Part of this study would utilize observational data sets derived from multiple sounding rocket experiments that would be combined with modeling methodologies based upon recently developed efforts based upon new laboratory findings.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.