Namonuito Atoll, also called Namonweito, Weito, or Magur Islands, is the largest atoll of the Federated States of Micronesia and of the Caroline Islands with a total area of , unless one considers the still larger Chuuk (Truk) Lagoon as a type of atoll in an early stage of development. In Micronesia, only Kwajalein Atoll of the Marshall Islands is still larger.
Namonuito Atoll lies in the northwestern region (Oksoritod) of Chuuk State, the largest federal state of the Federated States of Micronesia, about northwest of Chuuk Lagoon (measured from Pisaras Islet to the northern and western parts of the fringing reef of Chuuk Lagoon. It is roughly triangular in shape, with the base running along its southern side.
The southwest corner of the triangle is marked by Onoun islet, the main island (largest and most populated), also called Ulul.
The other islets lie mostly on the northeast side, from Piherarh (Pisaras) in the southeast corner to Makur (Magur) islet in the north corner. The 12 islets have an aggregate land area of only . The total population is 1,341 (census of 2000).
The reef rim of the atoll is submerged for the greater part and is marked by the lighter colour of the water over it. The depths on the reef range from . The reef appears to be in the process of formation and can be crossed at many places. The lagoon is not of uniform depth. Except for a patch, located west of Pisaras island, and a detached reef, with depths of , located about of Pisaras, there appears to be a depth greater than on the scattered lagoon coral heads.
Pisaras Island has coconut palms and other trees growing on it. Reefs extend northwest and west-northwest from the island, enclosing a shallow and foul bay. Ulul Island is densely covered with coconut palms. A drying reef fringes the island. There is a radio station on the island.
The atoll is home to five of the 40 municipalities of Chuuk state, listed in counterclockwise sequence, with population (2000):
Landsat visible color imageMunicipalityalternateor formernameLandareakm²Population(census2000)locationislandscoordinatesOnounUlul2.54598southwest cornerUlul IslandPiherarh Pisaras 0.80 227 southeast corner Wabonoru IsletPisaras IslandPielimal IsletWeltot IsletUnanu Onari 0.26 178 northeast rim Onari IslandBihof IsletBehiliper IsletAmurtride IsletOnouOno0.31182northeast rimOno IslandMakur Magur Islands 0.47 156 north corner Magur IslandMagererik IsletNamonuito AtollMagur Islands4.381,341
History Namonuito was first visited by Spanish explorers on the galleon San Jerónimo on 5 July 1566. At Pisaras Island, the rebel pilot Lope Martín and his gang of mutineers (thirteen soldiers and thirteen sailors) murdered Captain Pero Sánchez Pericón and other expedition members, and were subsequently marooned.Coello, Francisco La Conferencia de Berlín y la cuestión de las Carolinas: Discursos pronunciados en la Sociedad Geográfica de Madrid, Madrid, Imprenta de Fortanet, 1885, p.96Krämer, Augustin Ergebnisse der Südsee Expedition, Friederichsen, De Gruyter, 1908, p.197-198
Onou Island was later visited by Spanish naval officer Juan Antonio de Ibargoitia commanding the vessel Filipino in 1801 who charted it as Anonima (Anonymous).Sharp, Andrew The discovery of the Pacific Islands, Clarendon Press, Oxford, 1960, p.183
Onoun Airfield
Onoun Airfield is located on the west side of the atoll. Caroline Islands Air has chartered service. Aircraft land on a chipseal runway.
References
External links Sailing directions (enroute), page 263 exact islet coordinates historic census data, population densities about Juan Antonio de Ibargoitia