1. Abstract The alteration of the natural nighttime environment due to artificial light at night (ALAN) can disrupt ecological systems and affect human health. Inefficiencies in lighting use have downstream consequences for climate, economies and health. High resolution, regional-scale data of the nighttime environment is not readily available yet is necessary to address this issue. Mapping light emissions from a stratospheric balloon platform provides data of sufficient quality to further our understanding of the impacts and possible solutions to this health and environmental stressor. For this work, we designed and flew instrumentation on latex high altitude balloons for remote sensing of nighttime lights. We collected tens of thousands of images across an urban to rural footprint centered on the city of Indianapolis, Indiana (Fig. 1). Our results indicate land zoned for commercial use contributes 20.5% of all light emissions while only comprising 7% of land area. These results also corroborate an earlier study that road lighting contributes only an estimated 14% of total emissions, where our study shows a contribution of 24.3%, including other light sources on the roads. Comparing on-orbit observations from the VIIRS instrument to those collected with our method (Fig. 2), we can estimate the quantity of light unaccounted for due to the short (blue) wavelength insensitivity of the VIIRS sensor. This method can identify sources of light pollution on a regional scale. Our results indicate policy addressing commercial lighting may be the most efficient mitigation strategy in developed areas.

The Adler Planetarium’s Teen Programs engages hundreds of young people in authentic STEM experiences each year. Several of our programs focus on artificial light at night (ALAN), a critical environmental, health, ecological and astronomical issue. Our work in ALAN Community Advocacy and Education began in 2015 through Youth Organization for Lights Out (YOLO), a bilingual program in English and Spanish based in Chicago’s predominantly Mexican and Mexican-American Little Village neighborhood. YOLO program participants use tools to collect and analyze light pollution data, attend field trips to local and state dark sky sites, facilitate telescope viewing at the Adler and in their community, and develop prototype solutions and action plans to increase awareness of light pollution’s local effects in Chicago. Programs focused on Instrumentation and Research grew out of the Adler’s educational high-altitude ballooning program, Far Horizons. In 2018, Far Horizons astronomers and engineers began developing Mission NITELite (Night Imaging of Terrestrial Environments), a high altitude balloon-based light pollution mapping mission along with undergraduate interns. To complement NITELite, Far Horizons designed GONet (Ground Observing Network), a low-cost all-sky imaging system to measure sky quality at night as part of its Stratonauts teen program. In 2019, high school students helped design, test, and build 50 GONet units as a potential new standard for worldwide ALAN monitoring. In 2020, Adler teen interns are working with the Cook County Forest Preserves to quantify regional sky quality with GONets in support of an application for an Urban Night Sky Place designation from the International Dark-Sky Association. Reflecting the collaborative nature of science, teens in the Instrumentation and Research programs partner closely with peers in the Community Advocacy and Education programs, learning from one another’s perspective while undertaking joint projects.