Halemaumau Crater

Halemaʻumaʻu Crater is a pit crater located within the much larger summit caldera of Kīlauea in Hawaii Volcanoes National Park. The roughly circular crater floor is 770 meters (2,530 ft) x 900 m (2,950 ft) and is 83 m (270 ft) below the floor of Kīlauea caldera. Halemaʻumaʻu is home to Pele, goddess of fire and volcanoes, according to the traditions of Hawaiian mythology. Halemaʻumaʻu means "house of the `ama`u fern".

The crater is currently active, containing a lava lake. From 2008, when the current vent inside Halemaʻumaʻu crater first erupted, to April 2015, lava was present inside the vent fluctuating from 20 to 150 meters below the crater floor. On April 24, 2015 molten lava in the vent, known as the Overlook Crater, became directly visible for the first time from the Jaggar Museum overlook at the Hawaiian Volcano Observatory when the lava rose to an all-time high level since the Overlook Crater first opened. A few days later, on April 29, the lava started spilling over the rim of the Overlook Crater and onto the floor of Halemaʻumaʻu Crater, ultimately adding approximately 30 feet (9 m) of fresh lava to the crater floor. The lake level has since remained close to the rim, with a further minor overflow event in October 2016.

Early eruptions were recorded by oral history. One large one in 1790 killed several people, and left footprints in hardened ash of some Hawaiians killed by pyroclastic flows.

William Ellis, a British missionary and amateur ethnographer and geologist, published the first English description of Halemaʻumaʻu as it appeared in 1823.

Astonishment and awe for some moments rendered us mute, and like statues, we stood fixed to the spot, with our eyes riveted on the abyss below. Immediately before us yawned an immense gulf, in the form of a crescent, about two miles (3 km) in length, from north-east to south-west, nearly a mile in width, and apparently 800 feet (240 m) deep. The bottom was covered with lava, and the south-west and northern parts of it were one vast flood of burning matter, in a state of terrific ebullition, rolling to and fro its "fiery surge" and flaming billows.

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Wikipedia