Gemini telescopesTwo 8.1-meter groundbased telescopes with identical capabilities for use in the infrared, visible, and near ultraviolet. One (completed in 1998) is sited in the northern hemisphere on Mauna Kea in Hawaii and is known as the Gillett Telescope or Gemini North; the other (which saw first light in 2001) is in the southern hemisphere at Cerro Pachón in Chile and is known as Gemini South. The two telescopes together provide full sky coverage as well as similar performance in programs spanning both hemispheres. The telescopes are a joint venture between the USA, UK, Canada, Argentina, Chile, and Brazil. The US National Optical Astronomy Observatory (NOAO) administers the work of the telescopes through the NOAO Gemini Science Center (NGSC), headquartered in Tucson, Arizona. Image quality at near-infrared wavelengths is better than 0.1 arcsecond over a 1-arcminute field of view. The use of adaptive optics extends this near-diffraction-limited angular resolution to shorter wavelengths. A wide-field capability of 45′, for optical wavelengths, allows simultaneous spectroscopic sampling of multiple objects.
Collins Dictionary of Astronomy © Market House Books Ltd, 2006