The team on Cerro Pachón spent this week continuing the planned maintenance and recovery work in parallel. We are still off sky; here is where things stand as of September 25.
Power
Power supply stayed stable on generator through the week. On Monday the site switched briefly to the rental generator so the main unit could go through a scheduled preventive-maintenance window — the changeover itself took only a few minutes, and the site was back on the primary generator within about two hours, with no interruption to other systems. The electrical crew continues to staff the site around the clock. Work also continued on the Auxiliary Telescope’s transient suppressor.
Cooling and camera systems
Camera refrigeration and cryogenic work kept moving this week, with several circuits in the soak and recovery stages of the flush-and-recharge sequence, upgraded compressors are being prepared to be swapped into the cabinets under the telescope, and a battery in the camera’s utility trunk was swapped as routine maintenance. On the facility side, the Dynalene cooling system was powered up, confirmed reachable over the network, and brought into its first recirculation loop this week, with plans to extend circulation further to additional levels as work continues. Additional filtration equipment was also installed on the cold glycol loop to support that work, and the chiller that usually supports the server room continued to receive attention alongside the broader cooling restart. The Camera power was also restored to the on-board utility trunk and status assessments of all subsystems are ongoing.
Communications and computing
Recovery of summit IT services continued this week, with server and computer initialization work progressing in the server room as part of the broader effort to bring the data center back to full operation. This work is running in parallel with the cooling restart described above, since the two are closely linked. An LSSTCam onboard hardware computer swap is also progressing.
Dome and mechanical work
A weekend of rain and snow on the mountain kept the full crew from reaching the summit on Monday, which pushed back a scheduled mirror wash; the team caught up on it later in the week. The dome team continued daily test rotations using a temporary bypass procedure while preparing the mechanism for a return to normal automatic operation, and made progress on the first movement tests of one of the light/wind screen panels. Oil-tray guard installation got underway on the telescope’s azimuth bearing system, and the team started preparations for an upcoming hexapod component swap.
What’s next
With this much still in progress, we don’t yet have a specific return-to-sky date to announce, though we expect to be back on sky in a matter of a few weeks. We’ll continue to share updates here as the picture becomes clearer.
Congratulations to the team on another week of steady progress on the combined storm recovery and planned maintenance!