NASA satellite images show U.S. air quality improvements (Video)

Diminished nitrogen dioxide concentrations in 2011 (Credit: NASA)

Recent analysis of NASA satellite imagery showed that air pollution has decreased in the U.S. over the past decade, according to a NASA press release.

NASA’s Aura satellite hosts the Ozone Monitoring Instrument, a device that measures nitrogen dioxide concentrations from orbit. Nitrogen dioxide is a yellow-brown gas formed most commonly from burning gasoline or coal, and can cause respiratory issues especially for the very young and elderly.

Although average yearly pollution levels have decreased in major U.S. cities, about 142 million people in the nation still live with unhealthy levels of air pollution. Global satellites show that air pollution remains a major problem in other parts of the world.

Image: Diminished nitrogen dioxide concentrations in 2011 (Credit: NASA)