January 22, 2018 - To ensure optimal performance of the LSST telescope, a regular cleaning schedule of its mirrors will be implemented during operations. Weekly, the Primary/Tertiary Mirror (M1M3) and Secondary Mirror (M2) surfaces will be cleaned by spraying the surfaces with a carbon dioxide (CO2) “snow” which removes dust particles and other contaminants. Approximately every six months, M1M3 will be cleaned with neutral soap and water using very soft chamois mops, followed by de-ionized water rinsing and drying using small air knives around the mirror cell. Both of these cleaning procedures take place without removing the mirrors from the telescope, and are completed within one summit working day. Neither the CO2 nor wet contact wash will impact the nightly observing schedule.
In addition to these preventative maintenance activities, the mirrors will be stripped of their reflective coatings, washed, and recoated every few years. We anticipate the M1M3 (coated with aluminium) will be cleaned and recoated every 2 years, and the M2 (coated with protective silver) every 5 years. Reflectance monitoring will allow us to predict when this more time-intensive work is necessary, and it will likely be coordinated with other scheduled downtime.
The washing station, which provides for pristine optical surfaces before coatings are deposited, is a deliverable part of the coating plant contract. A Provisional Acceptance Test of the washing chamber will take place later this month at the Von Ardenne facilities in Dresden, Germany. The review includes observation of the washing boom, seen in this 30-second video provided by LSST Coating Chamber Engineer Tomislav Vicuna. This special machinery will remove the old mirror coating and wash the mirror prior to moving it into the coating chamber for recoating.
A related story about the LSST coating chamber, from March, 2017, can be found here.
LSST Assembly Integration Verification (AIV) Manager Jacques Sebag submitted this spectacular drone footage of the LSST facility, taken on December 28. The video was taken after the LSST team collaborated with subcontractor Besalco to move the facility mobile roof to the flat area located on the north side of the lower enclosure. Congratulations to all for this achievement at the end of 2017!
December 14, 2017 – The LSST mirrors and camera are designed to be transported on carts, as complete subassemblies, from the telescope to the maintenance level within the summit facility during LSST's ten-year survey lifetime. The mirrors will be recoated approximately every two years and the camera clean room will be available to support maintenance and servicing. Because the maximum load (the M1M3 on its cart) will approach 75 tons, and the equipment must move up and down 27 meters, a custom, robust lifting mechanism is required. PFlow Industries has built a unique 11-meter square Vertical Platform Lift for LSST, and December 7, on Cerro Pachón the folding-edge structure for its movable roof was successfully installed.
November 12, 2017 - LSST’s fiber-optic network, which will provide the necessary 100Gbps connectivity to move data from the summit of Cerro Pachón to all LSST operational sites and to multiple data centers, came one milestone closer to activation last week; the AURA LSST Dense Wavelength Division Multiplexing (DWDM) Network Equipment that LSST will use initially was installed in several key locations. DWDM equipment sends pulses of light down the fiber to transmit data, therefore a DWDM box is needed at each end of a fiber network in order for the network to be operational. In this installation project, the Summit-Base Network DWDM equipment was set up in the La Serena computer room and in the communications hut on the summit of Cerro Pachón.
November 9, 2017 - At CAID Industries in Tucson, the Surrogate Mirror has now been mounted to the Primary/Tertiary Mirror (M1M3) Cell. This is a significant milestone for both the Surrogate Mirror and for the M1M3 Cell, allowing the start of the next phase of integration: installing the figure actuators.
October 3, 2017 - LSST is a revolutionary project for a number of reasons, one of which is its commitment to building an Education and Public Outreach (EPO) program as novel and robust as LSST itself. The EPO team (pictured in the accompanying photo) is currently developing the infrastructure for the program to be delivered during operations; this process that is occurring in tandem with the construction of LSST's observational facility and other subsystem components. This long lead time allows for thoughtful and thorough prototyping, testing, and evaluation of EPO products so they'll be ready when LSST Operations begin in 2022.
September 18, 2017 - The total solar eclipse on August 21, 2017 captivated not just the astronomy community, but the public at large. Many individuals associated with LSST traveled to the path of totality to view the spectacle for themselves and share their knowledge with others. LSST Associate Scientist Keith Bechtol gave a talk to an audience at Rabun Gap Nacoochee School in Northeastern Georgia the day before the eclipse. He used the opportunity to deliver an inspiring talk about LSST and the unique opportunities offered by ambitious science projects--even for people who don't think of themselves as scientists.
Financial support for LSST comes from the National Science Foundation (NSF) through Cooperative Agreement No. 1258333, the Department of Energy (DOE) Office of Science under Contract No. DE-AC02-76SF00515, and private funding raised by the LSST Corporation. The NSF-funded LSST Project Office for construction was established as an operating center under management of the Association of Universities for Research in Astronomy (AURA). The DOE-funded effort to build the LSST camera is managed by the SLAC National Accelerator Laboratory (SLAC). The National Science Foundation (NSF) is an
independent federal agency created by Congress in 1950 to promote the progress of science. NSF supports basic research and people to create knowledge that transforms the future.