Science operations at the United Kingdom Infrared Telescope will conclude Sept. 15 so it can be decommissioned, the University of Hawaii announced Wednesday.

“Aging facilities and funding challenges, especially given the expiration of the UH master lease in 2033, in addition to the obligations contained in the UH Master Plan, led to the decision to end operations,” according to a UH press release

The U.S. Naval Observatory has sponsored scientific research at UKIRT for many years, supporting decades of discovery through the telescope, which opened in 1979.

UKIRT will become the third Maunakea telescope to be decommissioned.

The decommissioning of the first two Maunakea telescopes, the Caltech Submillimeter Observatory and the UH Hilo Hoku Keʻa Observatory, was completed in 2024.

In 2025, the UH Institute for Astronomy announced plans to remove UKIRT following the conclusion of its science mission. The decommissioning process is expected to be complete by 2030.

IfA assumed ownership of UKIRT in 2014 after the United Kingdom ended funding for the facility.

“UKIRT has had an extraordinary run and has been one of the most prolific telescopes on the planet,” Doug Simons, director of IfA, said in the press release. “For nearly five decades, it has expanded our understanding of the universe, helped train generations of astronomers and strengthened Hawaii’s reputation as one of the world’s premier locations for astronomical discovery.”

The telescopes on Maunakea rank among the world’s most scientifically productive collections of observatories, and UKIRT has been an important contributor to that legacy. It has helped scientists understand how stars and planets form, map vast regions of the Milky Way and study distant galaxies.

Eight full-time employees currently support UKIRT operations and will continue to have the opportunity to support operations through the Sept. 15 closure date.

Under the UH-developed Maunakea Master Plan and Maunakea Comprehensive Management Plan, or CMP, the university committed to reducing the number of observatories on Maunakea while continuing world-class astronomy and responsible stewardship.

The UH Hilo Center for Maunakea Stewardship oversaw the first two decommissioning projects. This fall, UH will hire a consultant to develop a detailed cost estimate, project schedule and permitting plan for the UKIRT decommissioning.

“Decommissioning is about honoring our commitment to care for Maunakea,” Greg Chun, CMS executive director, said in the press release. “Every decommissioning project is an opportunity to demonstrate that our commitment extends beyond astronomy to restoring these sites with care, respect and purpose.”

Management responsibilities for Maunakea are transitioning from UH to the Maunakea Stewardship and Oversight Authority, established by the state Legislature in 2022.