The grating and guard rail around the liquid nitrogen tank have been completed. This gives the contractors safer access to the controls during our filling.

The air and glycol (“Blue Thunder”) hoses arrived and installation may start as early as next week. This will actually shut down the structure for a day or two as these are carefully integrated into the azimuth cable wrap below the telescope.

The HRS instrumentation team came out from Austin and disassembled the HRS and packed the optics up. Some of the optics will just be stored while the coated optics are being shipped out to be recoated for the HRS upgrade. The HRS enclosure has been cleared and once some preliminary electrical work is done the inside of the enclosure will be painted flat black.

Our telescope operator and video production guru has completed a new video showing the installation of the temporary clean room frame. See http://het.as.utexas.edu/wfu/ This clean room will house the corrector when it arrives in late April.

A visiting engineer from Texas A&M was back this week with the doors and sides for the VIRUS enclosure. A lot of work continues to seal, plumb and install electrical components in the enclosures and annex.

In night time commissioning we attempted a rewind test. This is to measure the time it takes from the abort of one 20 minute trajectory and rewind and start a 2nd trajectory. It took 79 seconds to make this transition which is a little longer than we really wish but still within the 80 seconds from abort to guider acquisition. We hope to shave 9 seconds off this time so that we can have 10 seconds to have the metrology and guiders acquire their stars.

The mirror team has been getting ahead of their minimum swap rate by swapping another 5 mirrors this last week. They hope to have all of the older mirrors swapped out by the time we start re-commissioning the telescope.