Radar image of the "Big Island" of Hawaii.

From a remote outpost on the summit of Hawaii's dormant Mauna Kea volcano, 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.

Made possible through grants totaling nearly $200 million from the W.M. Keck Foundation and NASA, the observatory is operated by CARA for the California Institute of Technology and the University of California, and for the National Aeronautics and Space Administration (NASA), which joined the partnership in October 1996. The Keck I telescope began science observations in May 1993; Keck II began operation in October 1996.

Keck's capabilities make full use of the summit site. Surrounded by thousands of miles of relatively thermally-stable ocean, the 13,600-foot Mauna Kea summit has no nearby mountain ranges to roil the upper atmosphere. Few city lights pollute the viewing. For most of the year, the atmosphere above Mauna Kea is clear, calm and dry.

The University of Hawaii's Institute for Astronomy manages an 11.600-acre science reserve surrounding the summit. In the year 2000, a dozen major research telescopes occupied this reserve, representing a capital investment of more than $500 million and employment for hundreds of Big Island residents.

A view of the south ridge of the summit of Mauna Kea, taken from the Keck Observatory on the northern ridge. From left to right, the observatories are the Canada-France-Hawaii Telescope (CFHT), Gemini North, the University of Hawaii 88", and the United Kingdom Infrared Telescope (UKIRT).