Over the past several weeks, the Northeast U.S. has seen significant reductions in trace gases over many of its major metropolitan areas, such as New York City and Baltimore. Similar reductions in trace gases have been observed across the globe. These recent improvements in air quality have come at a high cost, as communities grapple with the widespread stay-at-home advisories that began about a month ago as a result of the spread of COVID-19. The animation shows satellite data of NO₂ from the Aura Ozone Monitoring Instrument (OMI) over the Northeast United States in March for each year from 2015 to 2020. Year-to-year variations in weather and trace gas emissions cause variations in the monthly means for individual years. March 2020 shows the lowest values as compared to any of the monthly values for March during the OMI data record, which spans 2005 to present. Caution: Further analysis is required to rigorously quantify the amount of the change in NO₂ levels associated with changes in trace gas emissions versus natural variations in weather.