The scale of the Rim Fire threatening Yosemite can be seen in these images from the MODIS instrument on the Aqua Satellite. This image was captured on August 22, 2013. As of today the fire is only 20 percent contained with almost 4000 firefighters engaged. The fire spans 184,000 acres according to the Incident Information Service.
This image from the VIIRS instrument on the Suomi NPP satellite shows the progress of the fire from August 23-26. The VIIRS day-night band is extremely sensitive to low light, making it possible to see the fire front from space at night. The brightest, most intense parts of the fire glow white, exceeding the brightness of the lights of Reno, Nevada, to the north. Pale gray smoke streams away from the fire, generally to the north.