October 19, 2006

Cleaning of the 200 inch telescope mirror at the HPWREN-connected Palomar Observatory

Telescopes at Palomar get a lot of use. It is a fact of life that their mirrors get dirty. The 200-inch mirror of Caltech's Palomar Observatory is no exception. Cleaning Palomar's big mirror is no easy feat. Pulling it out of the telescope takes an entire day. The quicktime movie shows the Palomar Observatory day crew pulling the 14.5-ton mirror out of the telescope, carefully washing it and recoating it with a new layer of aluminum. A successful coating deposits just a few grams of aluminum across the 200-inch disk making a layer only 3 millionths of an inch thick.

This image is one of many that were used for an narrated time lapse animation of the mirror cleaning process. A 153 megabyte MPEG2 and a 369 megabyte Quicktime version had been created, alongside a non-narrated 18 megabyte Quicktime movie of just the washing of the mirror.

W. Scott Kardel
Public Affairs Coordinator
Palomar Observatory
California Institute of Technology