Our current understanding of large scale structure formation in the Universe suggests that objects such as clusters of galaxies form hierarchically through the accumulation of smaller systems. Rarely, two roughly equal mass clusters will coalesce in a major merger. Major mergers have a profound effect on the cluster constituents - many interesting physical phenomena can be studied in this environment on the scales of galaxies to that of the entire Intra-Cluster medium. However, these studies are hindered by the difficulties in determining whether a cluster is a relaxed system, or if it has undergone some form of recent major merging, whilst major and minor mergers are difficult to disentangle. An effective signpost of a recent major merger is required, and thanks to the excellent spatial resolution of the Chandra X-ray satellite a solution may be at hand with the detection of "Cold Fronts" - thought to be evidence of a recent merger. In order to gain confidence in the use of cold fronts as a merger cue, we have constructed a sample of "Cold Front" clusters using archival Chandra images and are conducting follow up observations at optical and radio wavelengths to establish definitively their link with merger activity. In this talk, I will describe the cold front phenomenon, its application to cluster selection, and the sample that has been selected. I will also present and discuss the initial results to come from our follow up spectroscopy obtained with the AAOmega and MMT/Hectospec spectrographs. In particular, I will focus on the sub-structure detection analysis and the promising indications that cold fronts are robust indicators of major cluster mergers.

In this talk I present an analysis of the data produced by the Gattini cameras, located at Dome C in Antarctica, for the winter of 2006. Software to analyse the large data sets generated by the cameras is developed and presented along with key results showing the background sky brightness and cloud cover estimates. The background sky brightness is measured to be between 20.5 and 21.0 mag/arcsec^2. A lower bound for the amount of time with clear skies is estimated at 79.4% between May and October.

Dome A, Antarctica, has an elevation of 4100m and temperatures that can fall below -80?^?C. It is possibly the best astronomical site on the planet, especially at terahertz frequencies. We are currently developing PLATO (PLATeau Observatory), the third generation of our robotic site-testing observatories. PLATO will be deployed to Dome A by the olar Research Institute of China in the summer season of 2007-8 as part of their "PANDA" International Polar Year expedition.

PLATO differs from its predecessors, the AASTO and AASTINO, in that it consists of a separate power and instrumentation module. A suite of instruments from both UNSW and international collaborators will observe the site conditions. The instruments will be measuring sky emission and opacity in the visible and sub-millimetre, turbulence in the boundary layer and upper atmosphere, and meteorological conditions. These measurements will provide valuable site testing and scientific data. The instrumentation module will be powered by a hybrid system of solar panels and diesel generators. We have constructed a low-pressure environmental chamber and used it to successfully test the diesel engines at simulated Dome A altitudes. PLATO is fully autonomous, but control and data retrieval is also possible via the Iridium satellite network.