sci22091 — Announcement

Gemini-North Shutdown Extended

December 1, 2022

Update 1 December 2022:

The Observatory has progressed significantly on the plan to repair the Gemini North primary mirror and return to night-time operations. More thorough inspections of the mirror have not found any additional damage, and confirm that the damage is limited to a small area on the outer edge of the mirror. We anticipate repairs to be completed in January and a return to night-time operations sometime in February, barring unforeseen delays due to weather or other factors. Further updates will be posted on the Gemini homepage.

Original announcement:

On Thursday 20 October 2022 the 8.1-meter primary mirror of the Gemini North telescope, part of the International Gemini Observatory and operated by NSF’s NOIRLab, suffered damage to a small area on the edge of the mirror and outside the area collecting light for observations. There were no injuries associated with this event. 

While moving the primary mirror in preparation for stripping its reflective protected silver coating, it contacted an earthquake restraint on the facility’s wash cart, chipping the edge. A stop-work order was issued immediately and a thorough investigation by NOIRLab, Gemini, and external experts has begun to determine what happened and what is needed to repair the mirror. 

A comprehensive lessons-learned report will also be prepared to prevent similar events in the future. An Independent Review Board, chaired by Jim Oschmann, will review and approve the results of the investigation.

This process will proceed at a deliberate and careful pace; our primary concern is the safety of our staff. The timescale for Gemini North’s return to operations will be determined by the findings of the investigation and the repair plans. 

We will provide further updates as they become available.

About the Announcement



Gemini North telescope - side view

International Gemini Observatory/NSF’s NOIRLab/AURA/J. Pollard