Construction is well on its way. The pier being poured and the concrete now setting, the various braces have been removed allowing for a clear view of the structure’s foundation.
This will likely be a series of posts involving some very exciting news here at the observatory: We are adding a new observatory building complete with dome and telescope! Very much exciting times! The new structure will be 16’25’ in dimension with a 16′ diameter dome on the south side. The interior will be divided into two sections: the telescope/equipment room and the control room. A wall with large glass window will separate the two so that people can work with low-level red lighting while keeping the telescope and its sensitive instrumentation in the dark and away from the heat of humans which can cause disturbing air currents.
The telescope is a PlaneWave 0.70m diameter modified Dall-Kirkham optical system with two ports. One port will hold a CCD imager with filter wheel. The other will attach to a fiber-fed echelle spectrograph. It is difficult to imagine the scale of such an instrument. The telescope alone weighs over 1500 pounds! For a comparison here I am standing besides the same model of instrument at a recent American Astronomical Society meeting.
Ground breaking started a couple of weeks ago. Concrete pouring started today for the pier footing and the footing for the building’s foundation. This will help give a sense of scale the final structure.
School might get out in June, but the Observatory is a buzzing place with all sorts of activities while the students are away. The primary charge for us is completing the cleaning and maintenance work that needs to be done to keep all the equipment in top working order. This year, we also received a new optical tube assembly for the Kurtz Dome, necessitating some serious lifting and alignment procedures. Here is the list of activities done this summer to date (summer is not over just yet!):
- Dome cleanings: Just after students graduate, the first order of business is to give each dome a thorough cleaning. Observatories maintain a low level of sweeping, as this kicks up a lot of dust and makes the optics a real mess. In spring, the optics are thoroughly sealed in plastic bags, the cobwebs and pollen and dusted down from top to bottom, then the whole dome is vacuumed and wet-wiped.
- Batteries in the various components are replaced: there are little button batteries here and there for little things like ROM backups, and bigger things like illuminated reticles for the finder scopes.
- We installed the new 16″ ACF SCT telescope in the Kurtz Dome. The Takahashi refractor and the Celestron SCT were removed first. The mount saddle was configured for two optical tubes and was turned 90 degrees, so that required realignment. That done, the new 16″ OTA was put into place and counterbalanced. It is one heavy OTA at 75 pounds. The weights need to be in proper position to prevent too much stress on the mount’s drive systems. Once balanced, the whole system needed to be reconfigured for the larger tube using software that knows the extent to which the tube can travel without smacking into the pier. That would not be good!
- The Robotic Observatory had a complete software upgrade. Those who know me, know one of my mottos: if it is working, DO NOT upgrade anything. I hold to this as much as possible, but there are times when things are working, but the software manufacturers have control over us. In this case, the license for our internet-accessible server/control system was expiring, and they would not allow a simple renewal without software upgrade. Alas! Upgrading that required upgrading everything. The status now with the software is that the automated focusing software is not compatible with the other pieces. We focus by hand for now. That said, there are other gremlins in the system:
- The electronic focuser was getting stuck. A little dismantling and some lubrication fixed that. We had a solid run last night without any focuser issues.
- No focuser issues means that we must have had something else going on… nothing is perfect. Yes, the shutter on the CCD imager was getting stuck! After 40 flawless images, the images started to show the bright stars with vertical blooming down each column. This means that the shutter was remaining open as the CCD downloaded the images by pushing the pixel charges down to the readout registers. Sigh. The camera needs to be dismantled and diagnosed now. That is on the to-do list.
- New tripods were ordered for the portable telescopes which have a few benefits: They allow easy polar alignment; They can be adjusted for height (not all students are very tall); They are lighter, easier to carry around; They are much more stable than the piers we used to use.
- The spectrographic system in the Alden Dome has checked out perfectly.
- The Heliostat has checked out perfectly, though I am beginning to think about getting the mirrors a new aluminum coating.
- Tested a home-made grism (a diffraction grating system: grating + prism = grism) with a DSLR camera on the 16″ telescope. Results are encouraging and might be awesome to use with winter Astronomy 392 classes.