kea: see parrot.

Mauna Kea Observatories, astronomical observatory complex located on Mauna Kea peak, the "white mountain" on the island of Hawaii, at an altitude of more than 13,600 ft (4,145 m). Because of its height and excellent seeing, this site supports by far the largest astronomical facility in the world. It is operated by the Institute for Astronomy of the Univ. of Hawaii. The largest telescopes are the 33-ft (10-m) W. M. Keck telescopes (Keck I and II), each consisting of an array of 36 segmented mirrors; a computer adjusts each small mirror many times per second so that a single image is formed of the object under study. Keck I began observations in 1993, Keck II in 1996. The Subaru telescope, featuring a 327-in. (8.3-m) one-piece mirror, was formerly called the Japanese National Large Telescope. The 320-in. (8.1-m) Gemini telescope is one of an identical pair, the other being constructed atop Chile's Cerro Pachon. Together they will provide complete unobstructed optical and infrared coverage of both the northern and southern skies. Other instruments include the Canada-France-Hawaii telescope (142 in./3.6 m), the United Kingdom Infrared telescope (150 in./3.8 m), and the Infrared Telescope Facility (120 in./3 m), as well as two telescopes—the Caltech Submillimeter Observatory and the James Clerk Maxwell Telescope—used for observations in the submillimeter portion of the electromagnetic spectrum. Also part of the complex is the Hawaii Antenna of the Very Long Baseline Array, which is used for observations in radio astronomy.

Mauna Kea, dormant volcano, 13,796 ft (4,205 m) high, in the south central part of the island of Hawaii. It is the loftiest peak in the Hawaiian Islands and the highest island mountain in the world, rising c.32,000 ft (9,750 m) from the Pacific Ocean floor. It has many cinder cones on its flanks and a great crater at the summit. Its fertile lower slopes are used for agriculture, especially the growing of coffee beans; the upper slopes are snow-covered in winter. At the peak of Mauna Kea, where the dry air is ideal for optical and infrared astronomical observations, is the site of the Mauna Kea Observatories. The mountain is surrounded by the Mauna Kea Forest Reserve; the Mauna Kea Ice Age Natural Area Reserve is on the southern slopes.

Dormant volcano, north-central Hawaii island, Hawaii, U.S. Rising to 13,796 ft (4,205 m), it is the highest point in the state and is the chief feature of a state park occupying 500 acres (202 hectares). Its name means “white mountain,” referring to its snowcapped peak. Its dome is 30 mi (48 km) across and is the site of a major astronomical observatory. The volcano's lava flows have buried the southern slopes of the Kohala Mountains to the northwest, and its own western and southern slopes are covered with lava from its neighbour, Mauna Loa.

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