July 16, 2019 - This is a busy and exciting time on Cerro Pachón, as more large components of the telescope have now arrived at the summit. The LSST Primary/Tertiary (M1M3) mirror surrogate (the steel structure that will stand in for the glass mirror during testing) was transported from the port at Coquimbo to the summit in two pieces—it arrived at the LSST summit facility site on June 28th. The M1M3 mirror cell (the steel support structure for the mirror) stayed at the port in Coquimbo a few days longer, then followed the same route up the mountain, arriving on July 11. Both pieces of equipment were carried by Javier Cortez, SA transport vehicles. Like the LSST Coating Chamber and the M1M3 mirror, these very wide loads were driven slowly and carefully towards the summit over several nights, in what has by now become a well-rehearsed routine.
Meanwhile, inside the LSST summit facility building, preparations are underway for the coating of the Secondary Mirror (M2) in the Coating Chamber. To avoid overcrowding the area during this important activity, the M1M3 surrogate and the M1M3 cell be will be temporarily stored outside the building, protected from dust and weather by thick plastic wrap. After the M2 mirror has been coated and returned to its storage container, the surrogate and cell will be moved inside the building, and the M1M3 mirror cell will be installed on the M1M3 transport cart. The M1M3 surrogate, along with its support system, will then be integrated with the M1M3 cell and tested.