This is the way we wash our dome.
It is possible that, until today, the dome of the Hale Telescope has never been washed except by rain. We decided that it was time to change that. The dome is 135-feet high, making it a rather big job to wash the dome. A guy on a ladder with a garden hose pressure washer just isn't going to get it done.
Thankfully, the Palomar Mountain Volunteer Fire Department was able to come to our rescue.
The PMVFD, armed with a ladder truck and fire hose, was easily up to the task.
Seeing the crew in action spraying water onto the dome was a very impressive sight.
When it is time to wash different areas of the dome, you simply turn the 1000-ton dome past the firetruck.
The washing produced quite an impressive spray which led to some interesting photo opportunities.
It is pretty nice to be able to create your own rainbows and have a firetruck and a telescope dome at either end.
They have a pretty powerful pump in the ladder truck and it certainly could shoot water very high into the air. Alas, it wasn't quite able to knock that jet out of the sky. ;)
Thanks to George, Cliff, Greg (on the ladder) and the entire PMVFD for their assistance today.