A massive power outage occurred across the Maunakea summit area in the early morning on September 13, 2018 (Hawai'i Standard Time). The power supply to the summit facility of the Subaru Telescope was interrupted for nearly 4 hours.
Along with this power outage, one of the uninterruptible power supplies (UPSs) that supplies power to the telescope did not function properly, and the telescope stopped. The observatory staff attempted to reboot the UPS after power was back on, but it did not start.
An estimate of the needed recovery time cannot be made without careful investigation. Therefore we decided to cancel the open use observations from September 13 to at least October 1, 2018.
There was no human damage associated with the power outage. We are currently investigating the cause of the UPS's failure and the impact on the telescope and observing instruments. The observatory will take appropriate action based on the investigation to resume open use observations safely and promptly. Updated information on the prospects of recovery will be posted as soon as the information becomes available.
Dr. Michitoshi Yoshida
Director, Subaru Telescope