As part of the NASA Mars tracking contract, the Parkes Telescope's surface is being upgraded to make it more reflective and sensitive at X-band. The spacecraft that the telescope will be tracking from November 2003 to February 2004, will be transmitting at frequencies close to 8.5 GHz. The surface upgrade will improve the telescope's performance by about 1 dB (or 25%).
The new perforated aluminium panels will replace half of the remaining, original steel wire-mesh panels, thus taking the aluminium panels out to 55 metres diameter.
Beginning on 3 March, the observatory began a 5 week shutdown to perform the surface upgrade. It is anticipated that the re-panelling will take about three weeks to complete, with a further week or two to perform holography measurements and adjustments of the individual panels.
The new perforated aluminium panels, were manufactered by the firm, "Sydney Engineering Sales" (SES), to ATNF specifications using the methods first developed by Barry Parsons and Don Yabsley in the 1980's. The panels are manufactured to an accuracy of 0.25 mm RMS (within about 2 1/2 times the thickness of a piece of paper).
Barry Parsons is the ATNF Project Engineer and Mike Kesteven is the Project Scientist. Tom Lees is supporting the contractor, Sydney Engineering Sales, in the installation of the new panels. Ken Skinner is the SES project engineer who supervised the manufacture of the panels and now their installation. Sean and Craig Best manufactured the panels and are now delighted to be installing them.
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The panels were delivered in containers and positioned prior to being lifted onto the dish surface.
A large crane was used to lift the panels onto the surface.
The panels were lowered onto a platform, before being individually removed and placed on the dish surface for later installation.
The re-panelling began by first removing the steel wire-mesh panels.
The new perforated aluminium panels were then lowered into place before being secured by special adjusting bolts. This process was continued for each of the 60 segments.
Meanwhile, Barry Parsons is working on a new method of adjusting each of the panels individually. Here we see Barry making delicate adjustments to the panels. Actually, he is loosening the old holding-down bolts so that he and Lewis Ball can test two new possible methods to allow fine adjustments of the existing panels to match the greater thickness of the new panels.
Meanwhile, the re-panelling continues, with about half the surface already completed.
On 13 March, more panels were lifted onto the dish to complete the resurfacing.
On 6 March, the naked-eye comet, Comet NEAT was visible above the refurbished dish.