The Northwest United States experienced many wildfires during the summer of 2015. NASA’s Aqua satellite took the daytime image (left). One of the larger fires, the Okanogan Complex Fire in Washington consumed 91,314 acres (370 square kilometers, or 143 square miles) by August 20.
The Suomi NPP satellite captured the nighttime image (right) with its Visible Infrared Imaging Radiometer Suite (VIIRS) sensor. The VIIRS has a “day-night band” that is highly sensitive to very low amounts of light, allowing it to detect both city lights and the wildfires.