gsh7w@astsun.astro.Virginia.EDU (Greg Hennessy) (12/04/90)
There is a problem with the Imaging Pointing System (IPS) on the shuttle. The IPS is not stable, and has large drifts. This means that the planned calibrations of the HUT and WUPPE have not been done. Software patches have been developed, and uplinked, had at this time 11:30 AM Central Standard Time, Monday Dec 4th, the calibration of HUT and WUPPE is being redone. Currently the science plan is about 12 hours behind schedule, and probably will end up about 18 hours or so behind schedule. The impact on the science will be less than just the simple loss of time, since all of the high priority targets will be rescheduled. BBXRT has an independent pointing system, and after the alighnemt of their instrumetn, they will be able to observe independently. The observation needed for the alighment has been done, and the results of that calibaration are being checked currently. The UIT telescope is waiting for the IPS to start working before taking data. The instrument is fine, and if the IPS is not fixed in the next shift, UIT will just open its shutter and take pictures of random peices of the sky. Since the field of view of UIT is so large (40 arc minutes, twice the area of the full moon) theree will always be SOMETHING in teh field of view. The only concern is a very bright star in t he field of view may damage the camera. -- -Greg Hennessy, University of Virginia USPS Mail: Astronomy Department, Charlottesville, VA 22903-2475 USA Internet: gsh7w@virginia.edu UUCP: ...!uunet!virginia!gsh7w