Mauna Kea Information
Mauna Kea is a dormant volcano in the Hawaiian Islands, one of five volcanoes which together form the island of Hawaii. Pu'u Wekiu, one of numerous cinder cones on the summit plateau, is the highest point in the state of Hawaii at 13,796 feet (4,205 m). Mauna Kea is the tallest mountain in the world when measured from base to summit, since its base is located on the seafloor about 19,000 feet (5,800 m) beneath the surface of the Pacific Ocean, bringing its total height to about 33,000 ft (10,000 m). In the Hawaiian language, mauna kea means "white mountain", a reference to its summit being regularly snow-capped during the Northern Hemisphere winter.
The summit of Mauna Kea is considered to be one of the best astronomical sites in the world. For this reason it is home to many of the world's leading astronomical observatories. The summit is above approximately 40% of Earth's atmosphere and 90% of the water vapor, allowing for exceptionally clear images of the night sky. Additionally, the peak is well above the inversion layer, allowing up to 300 clear nights per year. Also, at 20°N latitude, much of both the northern and southern skies are visible. The fact that it is a shield volcano has meant that road transportation to the summit is relatively easy. The low population density of the Island of Hawaii means that there is little light pollution from man-made sources. All of these factors have made Mauna Kea an ideal location for state-of-the-art astronomy.
The Observatories at Mauna Kea, (MKO), are an independent collection of astronomical research facilities, located on the summit of Mauna Kea in a 500-acre special land use zone known as the "Astronomy Precinct," which was established in 1967. The University of Hawai'i manages the site and leases land to several multi-national facilities which have invested more than $2 billion dollars in science and technology.
The accommodation for research astronomers is located below the summit at 9300 feet (2835 meters) above sea level, and a visitor information station is located at 9200 feet (2775 meters). The summit of Mauna Kea is so high that scientists and other visitors are advised to stay at the lower level for 30 minutes to acclimate to atmospheric conditions before reaching the summit.
Telescopes found at the summit of Mauna Kea are funded by government agencies of various nations. The University of Hawai'i itself directly administers two telescopes. In total there are 12 telescopes at or around the summit of Mauna Kea.
| Telescope Name | Country / Institution |
| Caltech Submillimeter Observatory (CSO) | Caltech |
| Canada France Hawai'i Telescope (CFHT) | Canada, France, University of Hawai'i |
| Gemini North Telescope | United States, United Kingdom, Canada, Chile, Australia, Argentina, Brazil |
| Infrared Telescope Facility (IRTF) | NASA |
| James Clerk Maxwell Telescope (JCMT) | United Kingdom, Canada, Netherlands |
| Subaru Telescope | National Astronomical Observatory of Japan |
| Sub-Millimeter Array (SMA) | Taiwan, United States |
| United Kingdom Infrared Telescope (UKIRT) | United Kingdom |
| University of Hawai'i 88-inch telescope (UH88) | University of Hawai'i |
| University of Hawai'i 24-inch telescope (UH24) | University of Hawai'i at Hilo |
| One receiver of the Very Long Baseline Array (VLBA) | United States |
| W. M. Keck Observatory | California Association for Research in Astronomy |
Construction of telescopes on Mauna Kea has been a source of controversy in recent years. Native Hawaiian groups have protested that construction of additional telescopes would cause considerable environmental damage and further desecrate a site that they consider sacred. They consider that the summit of Mauna Kea is the home of the snow goddess, Poliahu.