The International Gemini Observatory

For more information, please visit: https://www.gemini.edu

Montage of the Gemini North and South Telescopes Image credit: Gemini Observatory

The aptly-named International Gemini Observatory operates twin 8-m optical/near-infrared telescopes from Maunakea on the Big Island of Hawaii and Cerro Pachón in Chile, providing full sky coverage in declination and 6 hours of difference in longitude. Gemini North is a neighbor of AEON+ facility CFHT and Gemini South shares Cerro Pachón with SOAR and the Vera C Rubin Observatory. Gemini is a founding member of AEON along with Las Cumbres Observatory and SOAR.

Each telescope is equipped with optical and near-infrared imagers, medium resolution optical and near-infrared spectrographs, and optical high-resolution spectrographs. Gemini North also has the Altair near-infrared adaptive-optics system with laser guide star. Up to three instruments are usable at each telescope on a given night and switching between them takes less than a minute. An eight channel instrument, SCORPIO, is under construction for Gemini South that will provide simultaneous imaging or longslit spectroscopy from 0.4 to 2.4 microns.

Gemini operates in queue mode on the majority of nights. Staff observers match observations to the current conditions. New observations, including Targets of Opportunity, are easily inserted into the observing plans. Gemini works within AEON using an existing API and plugins to the TOM Toolkit. Software improvements that are under development will provide enhanced automation based on 25 years of queue operations experience, more capable APIs, and a dynamic scheduler that will create observing plans for both telescopes together. This system, the Gemini Program Platform (GPP), is expected to enter operations in 2026.

The international Gemini Observatory, a program of NSF NOIRLab, is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the U.S. National Science Foundation on behalf of the Gemini partnership: the U.S. National Science Foundation (United States), the National Research Council (Canada), Agencia Nacional de Investigación y Desarrollo (Chile), Ministerio de Ciencia, Tecnología e Innovación (Argentina), Ministério da Ciência, Tecnologia, Inovações e Comunicações (Brazil), and Korea Astronomy and Space Science Institute (Republic of Korea).