This visible light/infrared composite image over Montana and Idaho was acquired by the Moderate-resolution Imaging Spectroradiometer on Aug. 23. The image shows the locations of actively burning wildfires (red pixels) and the thick shroud of smoke they produced (grey-blue pixels). There were 57 wildfires burning across both states. A single image can be up to 2,330 kilometers wide, allowing fire scientists to monitor a much larger area than can be covered on the ground or by aircraft. Also, because the satellite has detectors that are sensitive to thermal infrared wavelengths of 3.70 and 3.90 micrometers, it can detect fires on the surface even through heavy smoke.