Project PoSSUM, an acronym for Polar Suborbital Science in the Upper Mesosphere, is a 501(c)3 aeronomy research and education program that grew from the opportunity created by the 'Noctilucent Cloud Imagery and Tomography Experiment', selected by NASA's Flight Opportunities Program in March 2012. A custom instrument was developed for this experiment to produce high-resolution noctilucent cloud and OH-layer imagery coincident with in-situ temperature measurements and neutral and charged particle density measurements in a manner from which tomography may be constructed. This tomography aims to characterize the roles of gravity wave and instability dynamicsin the mixing and transport processes of the upper atmosphere. The experiment was the only manned flight opportunity ever selected by NASA.

The human component of the PoSSUM experiment provides opportunities beyond traditional funding sources for increased funding through private sources including participant tuition, commercialization f media products, and sponsorships. In June 2017, PoSSUM conducted a privately-funded airborne reserach campaign from High Level, AB using three camera systemsdesigned and constructed for the NASA 'PMC-Turbo' high-altitude balloon mission. Other privately-funded PoSSUM citizen-science reserch yielded publications in bioastronautics, human factors, and educational methods.

The human component also provides a means to inspire general audiences while communicating sciience. PoSSUM manages two educational programs at the Embry-Riddle Aeronautical University in Daytona Beach, FL and a third program at the Space Foundation in Colorado Springs, CO. These programs have drawn students from 24 different countries to learn about aeronomy, remote sensing of the mesosphere, and noctilucent cloud science while they conduct simulated suborbital missions using actual instrumentation in fully-pressurized spacesuits.