SSO Update

Published in the RSAA Lunations
Vol1 Issue30 1–31 July 2022

CURE Guide Camera

In 2019, the Apogee CURE Guide Camera failed and needed replacement.  Since there was no spare, the AAT team quickly and temporarily replaced it with a WATEC camera which has been working well.  In June 2022, the “temporary” solution was replaced with an engineered system based on a Moravian C4-16000 camera and filter wheel.  This is the same camera that is being used for the Hector guider on the 2dF top end.

Brian Taylor and David Brodrick completed the optical design and guide software (DRAMA) changes for the new camera before travelling to SSO for the first night of commissioning.  With help from Glen Murphy, Steve Chapman and Chris Tinney, the new camera was successfully installed and some basic guiding was achieved. However, the commissioning was thwarted by bad weather. This year has been an especially poor year for observing.

The second commissioning run was much more successful. A clear night with good seeing meant the new CURE Guide Camera could be focussed and made parfocal with Veloce. On the night, Murray Riding (night assistant) and Mike Sharrott were locked in the moving Cass Cage at various times to tune camera focus while guiding on a star (a possible sideline commercial opportunity as a thrill ride for AAT tours?).   This time Brian Taylor and David Brodrick could not handle the Mount Woorut weather or the extreme stress of riding in the Cass Cage and dialled in from Canberra.  Chris Tinney again provided invaluable expert help remotely while feeding the family and worrying about his electricity being turned off due to the high demand.

There are a few minor tasks to complete before the project can be signed off.  There are a couple of software bugs where DRAMA is being a drama and the “turn it off and on again” fix surprisingly did not work.  But the project is virtually complete due to the efforts of the whole team.  This project was a great collaboration between AITC (design, build, commission) and AAT (manufacture, install, commission and project management). Thanks go to the many that have been involved including David Brodrick, Brian Taylor, Antony Galla, Glen Murphy, Randal Darko, Zachariah Smith, James Cameron, Jamie Gilbert, Chris Ramage, Chris Tinney, Ben Montet, Ashley Anderson, Murray Riding, Steve Chapman, Zoe Holcombe, Tony Farrell, Dionne Haynes, and Rob Brookfield.

Mike Sharrott (Project Nagger)

Science verification with an automated 2.3-metre telescope

On June 10, an important milestone with the ANU 2.3-metre automation project was reached. For one week, the telescope was allowed to run automatically, selecting targets to observe from a pool of about 50 targets submitted by astronomers that had been awarded time during the quarter. The one week science verification run allowed us to assess how the automated telescope performs under realistic conditions. It did very well. At the end of the last night, we were running low on targets.

Without human intervention, the telescope would open up just before sunset, focus itself and observe a number of standard stars during twilight. Once dark enough, it then had to select the most appropriate target to observe (based on observing constraints and priorities provided by astronomers). Once selected, the telescope acquired the target, set up the instrument mode, started guiding if required, and then started the sequence of exposures defined by the astronomers. It did this while monitoring the weather conditions. At the end of the night, the telescope would close. During the morning and also in the afternoon, calibration frames would be taken.

The data have been sent to the astronomers who submitted observing requests. They will now process the data and provide feedback on the quality. Our long term aim is to process the data automatically and in real time. This will give astronomers more time to analyse the data.

An automated telescope is very efficient. On several occasions, the telescope had already slewed to and acquired the next target before the CCD for the last exposure of the previous target had been fully read out.  Furthermore, the data were taken when observing conditions are suitable. In other words, no time was wasted.

This important milestone would not have been possible without the generous support from the ANU Centre of Gravitational Astrophysics and the hard work of the AITC staff, in particular Ian Price and Jon Nielson.

Chris Lidman on behalf of SSO