Caltech Submillimeter
            Observatory California Institute
            of Technology

CSO Receives Conservation District Use Permit

February 2022: Conservation District Use Permit issued for Decommissioning Caltech Submillimeter Observatory from Maunakea  

2022 Feb 10

Caltech has received the final approval needed to begin decommissioning the Caltech Submillimeter Observatory (CSO) from Maunakea.

On January 14, 2022, the Hawai'i State Board of Land and Natural Resources unanimously approved the Conservation District Use Permit (CDUP) for the decommissioning of the CSO from the Mauna Kea Science Reserve.

The CDUP culminates the careful process required under Hawai'i law to address technical aspects of removal of the CSO and the restoration of its site, including a detailed review of the potential cultural and environmental impacts. The CDUP sets the terms and conditions that Caltech must follow during the decommissioning. Copies of the CDUP, the Final Environmental Assessment, and other planning documents can be found here:

"We are grateful to move forward with the deconstruction process," said Caltech physics professor and CSO Director Sunil Golwala, Ph.D. "Caltech aims to undertake the decommissioning this summer, with removal and restoration completed by the end of 2022," said Golwala. It will be the first observatory removed under the 2010 Decommissioning Plan for Maunakea Observatories.

During its lifespan, the CSO was one of the world's premier facilities for astronomical research and instrumentation development at submillimeter wavelengths.

The CSO's 10.4-meter submillimeter telescope, which came online in 1987 for use in research by astronomers at Caltech and other institutions, is housed in a compact dome near the summit of Maunakea. The telescope was used by scientists, including almost 200 student and postdoctoral researchers, to open a new submillimeter window on the universe. A summary of CSO's contributions to astronomy and astronomical instrumentation are available here: All the astronomical instruments were removed from the facility in 2015.

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