GPI is mounted on a side port of the instrument support structure of the Gemini South telescope. More information about Gemini Telescope may be found here
The Gemini Observatory is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), CNPq (Brazil), and SECYT (Argentina).
Gemini’s Mission
To advance our knowledge of the Universe by providing the international Gemini Community with forefront access to the entire sky.”