The Pacific Ocean is the largest ocean on Earth, covering more than 155 million square kilometres.
It stretches from the Arctic Ocean in the north to the Southern Ocean in the south, and lies between Asia and Australia on its western side and the Americas on its eastern side. The name comes from the Latin Mare Pacificum, meaning “peaceful sea,” a name associated with Ferdinand Magellan’s voyage across relatively calm waters.
The Pacific also contains the greatest ocean depth known on Earth: the Challenger Deep in the Mariana Trench. Its island groups include Polynesia, Micronesia, and Melanesia, while the Pacific Ring of Fire marks a zone of frequent earthquakes and volcanic activity around much of its rim.
The Atlantic is the second-largest ocean. The Pacific and Atlantic are sometimes compared by shape and circulation, but the Pacific remains substantially larger in area and volume.