While the monsoon flows over the Sonoran Desert from the 4 July to Labor Day, and the storms cause nothing but problems of cloudy skies to observers and lightning damage to our electronics, KPNO shuts down to pursue a variety of improvement projects and maintenance work. Almost all of the large-scale improvement projects involving seeing enhancements have been undertaken during this time. This summer is no exception, although we had a shorter shutdown than usual -- the last astronomer at the Mayall finished on the morning of 20 July and the first run for 1999B will start on the night of 30 August.
At the Mayall, beyond the usual computer and mechanical maintenance, the following major projects were on the schedule: new mirror cover to allow airflow over the primary, ducting for enhanced mirror cooling, encoding of the tip/tilt of the f/8 secondary for repeatable collimation, complete refurbishment of the control room, and keepers for the primary mirror defining units. The two weeks before the first observer will see a thorough optical tune-up, continued commissioning of the active primary support system (4mAPS), and an operations verification.
At the 84-inch, the optics will be aluminized and components of the coudé-train removed to enhance performance in the IR. The optics will be thoroughly collimated and operations verified here as well.
And last, and by no means least, the Mountain Programming Group has led a complete test to ensure that we will be ready for the new century. While each telescope has been tested in turn, a test was made in August of the mountain as a whole. We are ready to point to the correct positions on 1 January 2000.
As we have looked back at all of the improvements that have been completed the past decade to the telescopes on Kitt Peak, we wonder how we would have gotten them done without Summer Shutdown.
Bruce Bohannan, Tony Abraham (for the scores of individuals who worked so hard this past summer)