APO 3.5-m Site Report, 07/27/2023
There was no Users Committee meeting in August, but we do have a site report from Jamey:
3.5-m Telescope and Instruments Highlights, 6/27/2023 – 7/31/2023
1) Overview
APO weather for July has not been very monsoon-like. We have had relatively few thunderstorms and some nice clear skies.
There is a forest fire near APO that started on July 18. The “Apple Tree Fire” has grown to 270 acres and is approximately 4 miles southeast of APO. The USFS is using a “Confine and Contain” management approach to this fire, which means that the fire is being allowed to burn, with the USFS crews on site to limit fire behavior. Smoke from this fire has impacted some observing during the past two weeks.
July was a quiet month for class visits compared to June; we had one REU group visiting in the middle of the month. Telescope shutdown started on 7/26/23, and recoating of M1 is on track for the week of August 7th at the Lowell Discovery Telescope outside of Flagstaff.
2) Operations
3.5m Telescope: a failure of the M3 rotation drive system occurred. Parts are on order to restore the full motion of M3.
0.5m Telescope: Issues with the filter wheel motion are believed to be the root cause of the recent problems. The filter wheel is a legacy piece of equipment from a company that has gone out of business, therefore finding spares is difficult. If no spares are found the filter wheel will have to be replaced with more modern hardware.
KOSMOS is being warmed up for shutdown to do a vacuum cycle with a getter recharge.
The ARCTIC diffuser rotator service had to be postponed, and will be rescheduled for a later date.
Agile clock sync card is being reset manually as needed. The instrument thermoelectric cooler controls failed recently. Princeton Instruments will no longer support the camera or controller hardware. We are working to find and order surplus equipment in an attempt to repair it.
Echelle interorder light ratios (measure of scattered light in the instrument) are still quite good but are declining again in the warmer weather.
DIS scattered light on the red camera improved dramatically recently (attributed to a detector partial warm-up) and is currently considered to be very good, however, blue is still considered bad.
3) Other
Shutdown preparation work was ongoing throughout the month.
Next meeting
The next meeting will be on September 5 at 10:30 am MDT.
