Sunday, September 26, 2010

Mount Lemmon Sky Center update

I have had a hard time posting this month, due to being incredibly busy as well as being limited in my observing time.  One of the things that has taken up more of my time has been volunteering up at the Mount Lemmon Sky Center (MLSC).  Previously I have posted about my efforts up there, and the week of September 13th, the 24" RCOS scope went offline as the new 32" RCOS Schulman Telescope was installed!  I spent a bit of time up on the mountain during the installation of the scope and thought that these pictures may be of interest.

Above you can see the telescope assembled with the west fork arm opened up.  This fork arm contains the optical encoders that communicate the telescopes position in declination to the computer.  The east fork arm (not shown) contains the declination motor and brake.  One of the neat things about this telescope is that it operates with friction drives and is therefore very quiet and has none of the periodic error that is inherent to geared drive systems.

Above left is the secondary cage and the approximately 12 inch secondary mirror.  In the mirror you can see reflected the primary mirror covers.  These are opened and shut electronically and the scope was not yet operational when I took these images, so no picture of the primary mirror yet.  Above right, is the brains of this telescope...this box contains a computer, drivers, and all the electronics necessary to communicate with the mount and telescope. 

Finally, this pictures was taken several nights later when we went up to do some adjusting of the polar alignment of the mount. You can see how massive the scope is in relation to the computer desk to the right.  This scope is the largest scope in the State of Arizona dedicated solely to public outreach and education.   One of the reasons I have been spending so much time at the MLSC of late, is that in addition to the typical volunteer duties assisting with outreach programs, I am now training to begin conducting the SkyNights programs!  It is very exciting and quite a bit of work.  While the telescope is impressive, it is simply a tool that we use to provide guests with an opportunity to learn and experience the night sky in ways that they never have before.  Mount Lemmon is a fantastic location for this program. Just as satisfying as hearing a guest exclaim "WOW!!" when seeing a globular cluster for the first time, is the contemplative silence of guests as they appreciate that their own shadow being cast on the ground is actually blue and not grey or black.  I can say that I learn as much as the guests each time I am there. As evidence, take a look at the picture below.  This picture was taken just prior to sunset looking opposite the sun in the sky, to the east.  In it, you will see a mountain range in the distance, as well as what at first glance appears to be a second, higher mountain in the background.  Look closely and you will see that it is not in fact a high mountain in the distance;  Rather, it is the shadow of Mount Lemmon being cast on the atmosphere.  This is just one example of something that can be experienced at the MLSC, something that most people have never seen before.


  1. This is amazing, Alan, and very exciting to see! I'd love to be able to take a class up there sometime, though transportation is always an issue for us (our district won't allow buses to drive up Mt. Lemmon Highway). Best of luck in your SkyNights program - and let me know when you'll be up there and I'll bring the family for a visit!

  2. Thanks Wayne- I think there will be a time in the (hopefully) not too distant future where we will be able to have folks participate remotely. The other thing, is that the sky center does have trips that start at the UA and transportation up the mountain is included...I am not sure what that would mean to the district though.

  3. Do you have any large pictures of the friction drive? It looks very interesting, and it would be good to see the drive mechanism. thanks!

    1. Much has changed since 2010 from the TCS to some of the mechanical structure (improvements)...and the drive mechanisms are no pictures, sorry-