STS043-608-039 Miyako and Irabu Islands, Ryukyu Islands August 1991 This north-looking view shows Miyako Island and to its left (west) the smaller Irabu Island. Both are part of the Ryukyu Islands. The islands are the exposed tops of a submarine mountain range and are volcanic in origin. Miyako and Irabu Islands are generally flat with some low-undulating terrain. The land on the islands is used mostly for agriculture. Coral surrounds most of the coastlines of both islands.