Tropical Storm Chanchu formed in the western Pacific on May 8, 2006, roughly 500 miles east of the Philippines. The storm gradually built strength and size, reaching typhoon strength by May 11. It lost some strength as it crossed the Philippines, but once clear of the islands, it regained power and became a typhoon once again as it continued westward across the South China Sea.

This photo-like image was acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Terra satellite on May 14, 2006, at 10:45 a.m. local time (02:45 UTC). The storm has a huge spiral-arm structure in this image and a well-defined cyclone shape, with a distinct, but cloud-covered eye (sometimes known as a “closed eye”) in the center. Sustained winds in the storm system were estimated to be around 120 kilometers per hour (75 miles per hour) around the time the image was captured, according to the University of Hawaii’s Tropical Storm Information Center.