We would like to inform you about the situation after the fifth report (December 25, 2023, Hawaii local time) as follows.
１. Status of countermeasures against "abnormal reading of load sensors at the fix points of primary mirror"
The replacement of the load sensors at the three fixed points has been completed, and after the replacement, the reading of the load sensors is restored to the nominal values at all three points. Furthermore, as a result of investigating the load sensors which were replaced with the new load sensors, it was confirmed that the load sensors that were reading an abnormal value were malfunctioning.
２. Status of countermeasures against "damage on the primary mirror"
After the replacement of the load sensors, we started repairing the damage on the primary mirror on site. We have completed the repair by the end of last week.
We imaged the star using the guide camera of the prime focus spectrometer and confirmed that there were no major problems with the shape of the primary mirror.
We are currently analyzing the pointing direction accuracy of the telescope and the shape of the primary mirror, which will take a few weeks.
We plan to complete the restoration after inspection and let you know.
We sincerely apologize for the long period of telescope shutdown that causes the loss of your observing opportunities.
(Relevant Links)
Regarding the Suspension of Subaru Telescope Night Observation (5th Report)
Regarding the Suspension of Subaru Telescope Night Observation (4th Report)
Regarding the Suspention of Subaru Telescope Night Observation (3rd Report)
Suspension of Night Observations (2nd Report)
Suspension of Night Observations (1st Report)
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