9. Canton Atoll, Phoenix Islands, Pacific Ocean
Canton Atoll is a good example of a long-lived coral atoll. Like Tupai, it probably originated as a fringing reef developed around a volcanic island that has long since disappeared. Unlike Tupai, however, it is far distant from any above-surface volcanic structure. Its parent volcano long ago subsided deep beneath the sea. The atoll lies only 2.5° from the equator and can be subjected to long periods of drought. Although it is the largest island in the Phoenix group, only nine square kilometers (3.5 square miles) rise above sea level. The island was discovered in the early nineteenth century and named after an American whaling ship wrecked there in 1854. For several decades American companies extracted the valuable guano, but in the twentieth century Canton's attraction lay in its location on the route across the Pacific, as a fueling stop for early long-haul flights, hence the long runway on the north shore and the designation, on maps, of the lagoon as a seaplane anchorage.
There is insufficient soil to support crops, and now that the island no longer serves as a halfway house en route to somewhere else, there is no permanent habitation. Patterns of coral heads growing within the shallow water of the lagoon are clearly visible as a thin white network.
STS-9, November-December 1983. Picture #9-46-1835.