Gemini Observatory Background Information Page

Twin 8-meter Telescopes for the 21st Century

Gemini North with open wind vents and observing slit at sunset
Gemini North with open wind vents and observing slit at sunset
Gemini South with star-trails of the South Celestial Pole overhead
Gemini South with star-trails of the South Celestial Pole overhead


Global view of Gemini North and South with complete sky coverage

The Gemini Observatory consists of twin state-of-the-art 8-meter telescopes that are located in each hemisphere in order to provide complete sky coverage for astronomers in the 7-country Gemini partnership. The Gemini partnership consists of the United States, United Kingdom, Canada, Australia, Argentina, Brazil and Chile. Astronomers from each partner country can apply for time on Gemini regardless of institutional affiliation and time is awarded in direct proportion to each country’s contribution to the partnership.

Gemini 8.1-meter primary mirror after receiving new reflective coating

The 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. Gemini South is located at almost 9,000’ elevation on a mountain in the Chilean Andes called Cerro Pachón. Cerro Pachón shares resources with the nearby telescopes of the Cerro Tololo Inter-American Observatory and both observatories are managed by the Association of Universities for Research in Astronomy (AURA). The Gemini Observatory international headquarters is located in Hilo, Hawaii at the University of Hawaii at Hilo’s University Park.

Both of the Gemini telescopes have been designed to take advantage of the latest technology and thermal controls to excel in a wide variety of optical and infrared capabilities. One example of this is the unique Gemini coating chamber that uses "sputtering" technology to apply protected silver coatings on the Gemini mirrors to provide unprecedented infrared performance.

M-74, the Perfect Spiral Galaxy, as imaged by the Gemini Multi-Object Spectrograph during early commissioning

Gemini’s aggressive instrument program keeps the observatory at the cutting-edge by incorporating technologies such as laser guide stars and Multi-Conjugate Adaptive Optics, that will take astronomical imaging to new levels of resolution and sky coverage. Instruments on the twin Gemini telescopes are complementary and provide unique capabilities at each telescope that are in harmony with each site’s characteristics.

Finally, the Gemini telescopes have been engineered with modern networking technologies in mind and have been fully integrated into the Internet2 network. When combined with remote operations from the base facilities in Hilo and La Serena Chile, astronomers have the option of queue scheduling with participation via web videoconferencing. With the flexibility of queue scheduling and remote participation, researchers anywhere in the Gemini partnership will be assured the best possible match between observation, instrument and observing conditions.


Peter Michaud / pmichaud@gemini.edu / January 2, 2002