Tropospheric Emissions: Monitoring of Pollution (TEMPO)
Scientists study the atmospheres of many worlds with orbiting spacecraft, but Earth is the only planet where we can measure the effects of life — and of the negative impacts of civilization. When it is launched, NASA’s Tropospheric Emissions: Monitoring of Pollution (TEMPO) observatory will measure air quality in North America from a geostationary satellite, specifically tracking air pollution in unprecedented detail. The scientific instrument development is led by scientists and engineers at the Center for Astrophysics | Harvard & Smithsonian and NASA’s Langley Research Center.
Artist's impression of the satellite that will carry the TEMPO instruments for monitoring air quality and pollution in North America.
The Satellite and the Science
TEMPO is part of NASA’s Venture Class Missions program, a set of low-cost space probes, as well as the Earth System Science Pathfinder (ESSP) program of Earth observatories. The scientific instruments for TEMPO will be carried aboard a commercial communications satellite in early 2023, which will have a geostationary orbit, staying above precisely the same spot on Earth’s equator. That will allow TEMPO to observe variations in air quality across the whole of North America on an hourly basis.
Air pollution comes from a variety of sources, including industry, the burning of fossil fuels for power, agricultural practices, and international transportation. These sources fluctuate in time and the pollutants they produce can be carried long distances by air currents. TEMPO’s instrument is a spectrometer designed to measure ultraviolet and visible light, collecting information about common pollutants such as nitrogen dioxide, ozone, and aerosol particles. The mission will be able to look at air quality with incredibly high resolution capable of distinguishing details in cities.
TEMPO will be the first space-based mission designed to provide hourly reports on air pollution, which in turn will be essential for researchers and public officials tracking air quality. The CfA | Harvard & Smithsonian is taking the scientific lead on the project, which includes collaborators from NASA, the Environmental Protection Agency, and other research institutions in the US, Canada, Mexico, Cuba, Korea, Europe, and Canada. TEMPO will be the North American component of a constellation of Earth-observation satellites monitoring air pollution.
An illustration of TEMPO scanning the continental United States.