The sun star (Solaster stimpsoni) is a large species of starfish that grows to a maximum size of 20 inches (50 centimeters) in diameter. It can have between eight and twelve arms, but is usually found with ten. The upper surface has a distinctive reddish orange color. The arms are long, slender, and tapering, each with a dark, purplish-gray contrasting stripe. This species is found in the seas of Japan, and along the western coast of the United States from central California north to Alaska. It feeds on sea cucumbers, tunicates, lamp shells, and sea pens.