On July 11, 2017, the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite captured this image of wildfire smoke filling valleys in southern British Columbia. Actively burning areas, detected by MODIS’s thermal bands, are outlined in red. Hundreds of wildfires were burning in the province on that day, according to the British Columbia Wildfire Service.

NASA image by Jeff Schmaltz, LANCE/EOSDIS Rapid Response. Caption by Adam Voiland.