Howland Island, Pacific Ocean
Howland Island is a United States possession located in the north Pacific between Australia and the Hawaiian Islands. Prior to 1890, organic nitrate (guano) was mined from the island by both the United States and the British. This tiny island (1.6 km2) is currently part of the U.S. National Wildlife Refuge system, and provides nesting areas and forage for a variety of birds and marine wildlife.
The island is composed of coral fragments and is surrounded by an active fringing reef. White breakers encircling the island indicate the position of the reef. Astronauts aboard the International Space Station photograph numerous reefs around the world as part of a global mapping and monitoring program. High-resolution images such as this one are used to update geographic maps of reefs and islands, assess the health of reef ecosystems, and calculate bathymetry of the surrounding ocean bottom.