More than 95% of the world’s population lives in areas where air pollution exceeds standards designated to protect human health. Nitrogen dioxide (NO2) is an atmospheric pollutant that is found in high concentrations in cities around the world. It is generated through processes including the combustion of fuel in air and is emitted from cars, transport vehicles and power plants. NO2 can also lead to the formation of atmospheric haze, smog and acid rain. Because NO2 is chemically reactive, it varies greatly in time and space within the atmosphere. However, this variability cannot be captured by available monitoring approaches. Therefore the research team is building a spacecraft that will measure NO2 in the air within cities across the Unites States and internationally.

NO2 measurements made by the spacecraft will resolve spatial gradients at sub-kilometer scales, representing an order of magnitude higher spatial resolution than current space-based instruments. The data will be used to develop our understanding of the emission, chemistry and transport of NO2 in the atmosphere and to improve interpretation of current satellite NO2 observations. To obtain the data, a scientific  instrument (a near infra-red slit spectrograph) and a spacecraft bus will be built and launched into space in order to collect measurements from Low Earth Orbit.