The blogger is back from a summer vacation. Plenty of activity at the telescope…

The 97 point test was completed a few weeks back and that data in under analysis. A mount model based on the previous 21 point test has been installed and tested. In the last 2 weeks a great deal of reliability has been added to the tracker software. One of the mechanical engineers from Austin was out this week reinstalling the tip/tilt camera, DMI and a new sky camera. On this last wednesday they use that camera to acquire a few fields and make sure the basic pointing of the telescope has not been lost. In addition to a few bright stars the group observed an open cluster just to see what the image quality might be for future plate scale analysis. Today the tip-tilt camera and DMI were used during several trajectories. This is a small milestone. We can use this data to refine the mount model with respect to the primary mirror (best done after we piston the array).

The mirror team has installed the last 4 mirrors into the array and the array is fully populated. We will start mirror swaps when the Remote Thermal Area project is complete and we have a chance to commission the strip and wash room for acid vapor removal. In the mean time the mirror team have measured the array with a sphereometer so that we can implement a piston move in the coming week.

The contractors on site have finished the silver tape application to the control and services building and next week they will start on the Krabbenhut. The mechanical contractor continue to work on the insulation that goes around the lines/pipes out to the remote thermal area. Last week the dirt works contractors finished the piers down the side of the mountain which will carry the acid vapor from the strip and wash room as well as the heat from the control and services building. The contractors are now working on the acid ducting inside the building and the conduit piers on the side of the Krabbenhut. The electrical contractors completed the move of one of the transformers from outside the control and services building to inside the Krabbenhut. This required the HET to operate from a generator for nearly a week. Big thanks to the McDonald Physical Plant team for allowing us to use the generator and keeping it filled over the weekend so that our sewer system would not be in jeopardy.

In the past week and this week the contractors on site continue to work on their projects. Veliz Construction is half way done with the application of the silver tape to lower the emissivity of the control and services building next to the dome. We expect them to take about 2 weeks to finish the rest of the tape work if the afternoon rains keep their current pattern and stop their work. ARC Mechanical continue to populate the vault with freon, glycol and other lines as well as connecting up to the inside of the building. This work progresses slowly.

We have gotten the approval for the opto-mechanical technician position. If you have interest or know someone interested in working in the beautiful Davis Mountains and working with the optics of one of the largest telescopes in the world please have them apply to: job number 140715014211

Last week we had the metrology team out from Austin and reinstalled the VAT, tip-tilt camera and VAT on the telescope. This trip we had much greater success. We were able to get the system aligned and got a return from the DMI. We also were able to turn the VAT around and point at the sky. We got our first trajectory and followed the star we actually desired for 20 minutes in which time the star did not drift appreciably. We did have some problems getting trajectories to start so that was the focus of the work this week. After a few days of digging we found a variable that was defined in the wrong part of the code and with the variable moved to the right location we were able to run 8 trajectories one after another and also ran trajectories that simulated stars moving in the East and North (we had been working in the South were there is little rotation and the trajectories move more quickly). This is a big break through!

The 2013-3 period started Aug 1 and will officially end when the Wide Field Upgrade begins, Aug 12. After August 12th we will be removing 46 mirrors over 5-8 days. During that time we will attempt science with an ever decreasing pupil size an with growing scattered light.