Observatories in Hawai‘i, USA

The Haleakala High Altitude Observatory Site, on the Island of Maui, is the site of Hawaii’s first astronomical research. "Seeing" conditions on Haleakala can be as good as on Mauna Kea, a site recognized to have the best astronomical conditions for ground-based observatories.
The 4,205 meter (13,796 ft) high summit of Mauna Kea in Hawaii houses the world’s largest observatory for optical, infrared and submillimeter astronomy. Telescopes are operated by astronomers from eleven countries. 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.
Special thanks to the University of Hawaii, Institute for Astronomy, CHFT and Keck Observatory for organizing my visit of the observatories.