Keck telescopes
Keck Observatory is an astronomical observatory on Mauna Kea, a mountain on the island of Hawaii. The observatory consists of two identical telescopes, Keck I and Keck II, which are the largest optical telescopes in the world. Keck I was completed in 1992; Keck II, in 1996. The California Association for Research in Astronomy, which is a partnership of the University of California and the California Institute of Technology, operates the observatory. The facility's full name is the W. M. Keck Observatory. Keck I and II collect and focus visible light waves and infrared (heat) waves from objects in space. One use of the telescopes is to analyze radiation coming to Earth from the farthest known galaxies. Astronomers can use the information gathered to determine a galaxy's distance, size, age, and other characteristics.
Excerpt from the "Keck Observatory" article, The World Book Encyclopedia © 1999