I regret to announce that the APO 3.5-meter will be taken out of service starting tomorrow, Dec 1 2003, for unscheduled/emergency diagnosis and repair of a problem with the secondary mirror motion actuators. The telescope will be operated tonight (Nov 30) with the scheduled science programs but will be shutdown immediately if there are any signs of problems with the secondary motions, at the sole discretion of the on-duty Observing Specialist(s) of course. This work is expected to take approximately 5 days, so that the telescope could return to science operations as early as the evening of Friday, Dec 5. However, there is always a significant uncertainty in such estimates, depending on the exact nature of the problem, how smoothly the work goes and so forth. A shutdown as along as a week is a reasonable possibility as well. Attempts to move the secondary on recent very cold nights showed indications of a significant mechanical malfunction; when temperatures warmed on subsequent nights, the problems disappeared. The goal of this unscheduled shutdown is to correct the problem before cold weather returns and causes damage that will require a much longer shutdown and perhaps considerable expense. Updates to the situation will be posted to apo35-general as further information becomes available. Ed Turner APO APO APO APO APO Apache Point Observatory 3.5m APO APO APO APO APO This is message 724 in the apo35-general archive. You can find APO the archive on http://www.astro.princeton.edu/APO/apo35-general/INDEX.html APO To join/leave the list, send mail to apo35-request@astro.princeton.edu APO To post a message, mail it to apo35-general@astro.princeton.edu APO APO APO APO APO APO APO APO APO APO APO APO APO APO APO APO APO