The Mauna Kea Telescopes

Hawaii is Earth’s connecting point to the rest of the Universe.  The summit of Mauna Kea on the Island of Hawaii hosts the world’s largest astronomical observatory, with telescopes operated by astronomers from eleven countries. The combined light-gathering power of the telescopes on Mauna Kea is fifteen times greater than that of the Palomar telescope in California — for many years the world’s largest — and sixty times greater than that of the Hubble Space Telescope.

There are currently thirteen working telescopes near the summit of Mauna Kea. Nine of them are for optical and infrared astronomy, three of them are for submillimeter wavelength astronomy and one is for radio astronomy. They include the largest optical/infrared  telescopes in the world (the Keck telescopes), the largestdedicated infrared telescope and the largest submillimeter telescope in the world is situated at a lower altitude two miles from the summit.

W. M. Keck/Subaru Observatories with a view to Maui in the background

Mauna Kea (“White Mountain”) is a dormant volcano on the island of Hawaii, the largest and southernmost of the Hawaiian Islands. Mauna Kea is unique as an astronomical observing site. The atmosphere above the mountain is extremely dry — which is important in measuring infrared and submillimeter radiation from celestial sources – and cloud-free, so that the proportion of clear nights is among the highest in the world. The exceptional stability of the atmosphere above Mauna Kea permits more detailed studies than are possible elsewhere, while its distance from city lights and a strong island-wide lighting ordinance ensure an extremely dark sky, allowing observation of the faintest galaxies that lie at the very edge of the observable Universe. A tropical inversion cloud layer about 600 meters (2,000 ft) thick, well below the summit, isolates the upper atmosphere from the lower moist maritime air and ensures that the summit skies are pure, dry, and free from atmospheric pollutants.

W. M. Keck Observatory
From a remote outpost on the summit of Mauna Kea astronomers at the W. M. Keck Observatory probe the deepest regions of the Universe with unprecedented power and precision.

Their instruments are the twin Keck Telescopes, the world’s largest optical and infrared telescopes. Each stands eight stories tall and weighs 300 tons, yet operates with nanometer precision. At the heart of each Keck Telescope is a revolutionary primary mirror. Ten meters in diameter, the mirror is composed of 36 hexagonal segments that work in concert as a single piece of reflective glass.

Subaru Telescope
The 8.3-meter diameter optical/IR Subaru Telescope operated by Japan and is an optical-infrared telescope. The telescope represents a new generation in telescope design not only because of the size of its primary mirror with an effective aperture of 8.2 meters, but also because of the various revolutionary technologies used to achieve outstanding performance. An active support system that maintains an unprecedentedly high mirror surface accuracy, a new enclosure design to suppress local atmospheric turbulence, an extremely accurate tracking mechanism using magnetic driving systems, seven observational instruments installed at the four foci, and an auto-exchanger system to use the observational instruments effectively are just some of the unique features associated with this telescope.

NASA Infrared Telescope Facility
The IRTF is a 3.0 meter telescope, optimized for infrared observations, and located at the summit of Mauna Kea, Hawai`i. The observatory is operated and managed for NASA by the University of Hawai`i Institute for Astronomy, located in Honolulu. NASA provides the costs of operation and NSF provides funding for new focal plane instrumentation through the peer review process. Observing time is open to the entire astronomical community, and 50% of the IRTF observing time is reserved for studies of solar system objects.

Canada-France-Hawaii Telescope
The CFH observatory hosts a world-class, 3.6 meter optical/infrared telescope. The observatory is located atop the summit of Mauna Kea, a 4200 meter, dormant volcano located on the island of Hawaii. The CFH Telescope became operational in 1979. The mission of CFHT is to provide for its user community a versatile and state-of-the-art astronomical observing facility which is well matched to the scientific goals of that community and which fully exploits the potential of the Mauna Kea site.

Gemini Telescope
An 8.1-meter optical/IR telescope operated by a consortium of seven countries.

The Gemini Observatory consists of twin 8-meter optical/infrared telescopes located on two of the best sites on our planet for observing the universe. Together these telescopes can access the entire sky.

The Gemini South telescope is located at almost 9,000′ elevation on a mountain in the Chilean Andes called Cerro Pachon. Cerro Pachon shares resources with the adjacent SOAR Telescope and the nearby telescopes of the Cerro Tololo Inter-American Observatory. The Frederick C. Gillett Gemini North Telescope is located on Hawaii’s Mauna Kea as part of the international community of observatories that have been built to take advantage of the superb atmospheric conditions on this long dormant volcano that rises almost 14,000′ into the dry, stable air of the Pacific. The Gemini Observatory’s international headquarters is located in Hilo, Hawaii at the University of Hawaii at Hilo’s University Park.

United Kingdom 3.8-meter infrared telescope
The world’s largest telescope dedicated solely to infrared astronomy, UKIRT is sited in Hawaii near the summit of Mauna Kea at an altitude of 4194m above sea level. It is owned by the United Kingdom Particle Physics and Astronomy Research Council and operated, along with the James Clerk Maxwell Telescope (JCMT), by the staff of the Joint Astronomy Centre, which is located in Hilo. The operation and development of UKIRT are overseen by the UKIRT Board.

Caltech Submillimeter Observatory
The Caltech Submillimeter Observatory (CSO) is a cutting-edge facility for astronomical research and instrumentation development. It is simultaneously one of the world’s premier submillimeter telescopes and one of the easiest to use. It consists of a 10.4-meter diameter Leighton radio dish situated in a compact dome near the summit of Mauna Kea, Hawai’i. The telescope is operated by Caltech under a contract from the National Science Foundation (NSF) and has been operating on a regular basis since 1988. It is open to the astronomical community, with most of the observing time available for non-Caltech observers.

James Clerk Maxwell Telescope
15-meter diameter telescope for submillimeter astronomy operated by the UK, Netherlands and Canada and is the largest astronomical telescope in the world designed specifically to operate in the submillimeter wavelength region of the spectrum. The JCMT is used to study our Solar System, interstellar dust and gas, and distant galaxies. It is situated close to the summit of Mauna Kea, Hawaii, at an altitude of 4092m.

UH 2.2 meter telescope
Optical/IR telescope used mainly by UH faculty and graduate students. The 2.2-meter telescope was the first large telescope constructed on Mauna Kea. It went into operation in 1970, and its early successes showed the excellent image quality and observing conditions at the top of Mauna Kea.

UH 0.6-m telescope
The first telescope on the mountain in 1969, it is now used mainly for undergraduate student training and for instrument development.

Submillimeter Array
Eight 6-meter submillimeter antennas operated by Smithsonian Astrophysical Observatory and Taiwan. The Submillimeter Array (SMA) explores the universe by detecting light of colors which are not visible to the human eye. It receives millimeter and submillimeter radiation, so named because its wavelength ranges from 0.3 to 1.7 millimeter, or 0.01 to 0.07 inches.

The main source of millimeter and submillimeter radiation is cold interstellar material. It consists of gas, dust and small rock-like bodies. This material is also the substance out of which stars and planets are formed. Detecting submillimeter emission therefore plays a vital role for studying the birth and death of stars. When stars are born out of dense interstellar clouds, their first visible light is trapped within them. The SMA can see into those clouds and acquire detailed images of the submillimeter light and thereby witness the birth of a star where optical telescopes or human eyes can just see darkness.

Very Long Baseline Array
The westernmost antenna of the 25-m diameter Very Long Baseline Array is situated 3 miles below the summit. The VLBA is a system of ten radio-telescope antennas,each with a dish 25 meters (82 feet) in diameter and weighing 240 tons. From Mauna Kea on the Big Island of Hawaii to St. Croix in the U.S. Virgin Islands, the VLBA spans more than 5,000 miles, providing astronomers with the sharpest vision of any telescope on Earth or in space. Dedicated in 1993, the VLBA has an ability to see fine detail equivalent to being able to stand in New York and read a newspaper in Los Angeles.

How to have a safe and enjoyable visit to Mauna Kea summit