Parkes Observatory report

Staff

In December 2004 Laurelle Price left the Observatory after five years of sterling service in the Visitors Centre, where she had been one of two part-time staff forming the backbone of the team serving more than 100,000 visitors a year. Greg Ballantyne joined the Visitors Centre as a casual staff member in December.

Tom Lees is on extended sick leave after shoulder surgery in mid-December. The operation was a success, but the recovery will take some weeks and Tom hopes to return to work around mid-March. In the meantime we are pleased to welcome Scott Brady, who is very capably filling Tom's role in the site services group.

We were sad to farewell Jess Lees, our trainee in Administration. Jess performed admirably in all facets of her role during her year with us, and we wish her every success in her future studies. Kayla Strudwick will join the Observatory staff as the new administrative trainee in the second week of February.

This summer the Observatory hosted its first Vacation Scholars. Michael Klinkert worked with John Smith, VC Manager and coordinator (see below) and Peter Hansen worked with Lewis Ball and Mike Kesteven on the wind loading on the telescope (see the report on page 24).

Bushfires

A menacing grass fire broke out in the vicinity of the Observatory on 30 November 2004, creating serious concern and interrupting observing. Fortunately local fire brigades contained the fire that evening, relieving any immediate threat to the Observatory. However the remnants of the fire were rekindled by strong winds during the afternoon of the following day, with the front passing within about one kilometre of the Observatory before racing North and prompting the evacuation of Alectown.

As happens in such circumstances, the flow of information was less than perfect and initial reports by local authorities that the Observatory had been completely destroyed were grossly exaggerated! A number of staff with fire-fighting training patrolled the boundaries of the Observatory and fire breaks were significantly widened. Two other trained staff provided direct assistance to local bush fire-brigades in containing the fire and mopping up.

While no houses were lost and there were no injuries, a number of the Observatory's neighbours suffered significant losses of crops, fences and stock. A full assessment of the Observatory's preparedness for and response to the situation has been completed. The outcome of the assessment was generally positive. Some opportunities for improvement are already being acted upon.

Visitors Centre and Outreach

Over the 2004 calendar year the Visitors Centre hosted approximately 118 000 members of the public. The Visitors Centre enjoyed high visitor numbers over the Christmas, New Year and Parkes Elvis Festival season, with up to 1000 people visiting each day. During this period, a trial of extended opening hours was carried out. Extended hours are likely to continue during school holidays and long weekends.

The original proprietors of the "dish café", Andrea and Michael Carter, sold the business in December after nearly two years of operation. Andrea and Michael conceived the idea of having a cafe at the Observatory, and worked with ATNF and CSIRO staff for around two years to realise their vision. The cafe has proved a most popular addition to the facilities for Observatory visitors. After running the cafe seven-days-a-week, Andrea and Michael will now have more time with their three young children. We thank them for their contributions to the Observatory, and wish them well for the future.

The new proprietors of the cafe are Craig and Rochelle Smith. Craig is a qualified chef and has 20 years experience in the food industry. The menu has changed but the emphasis on great coffee and high quality food at reasonable prices remains.

This summer ATNF had its first Outreach Summer Vacation Scholar, based at Parkes. Michael Klinkert developed materials and activities for schools visiting the observatories. The material is already in use at Parkes and will be further developed for use at Narrabri.

The Observatory's partnership with Swinburne Centre for Astrophysics and Supercomputing continues to be rewarding. Swinburne and ATNF are currently working on a 3D virtual tour of the telescope, an exciting project considering the number of visitors wanting to see inside the telescope. Much of the tour footage will be shot at the beginning of the April 2005 observing term and we expect the show to premiere towards the middle of the year. In January, Swinburne's latest 3D show "After Stars" started screening at the visitors centre. "After Stars" follows a red supergiant that is about to explode and considers whether it will produce a black hole or a pulsar. The show has proved popular, especially since it relates to astronomy conducted at Parkes.

Operations

Telescope operations this year have continued to be largely trouble free, with 1.5% of time lost to equipment faults in the year to date. The single most significant fault was the failure of one of the Wideband Correlator (WBC) samplers in late January; this has now been fixed. The pattern of high winds in the months December January continues, with 4.8% of time this year to date lost to weather, rather more than the usual annual average.

Receivers

A problem of growing concern has been instabilities in some of the 20-cm multibeam receiver channels. Three channels, beams 11b, 12b and 13b, are now showing some level of short-term instability in gain that are badly compromising pulsar search observations. The problem in channel 13b is also having some impact on HI (GASS) observations. These problems have arisen since re-installation of the refurbished receiver last September, and are thus far confined to the old LNAs. (Owing to resource conflicts with other ATNF engineering projects, only about half of the original LNAs could be replaced with new units during the initial refurbishment). A second-stage refurbishment replacing all old LNAs is tentatively scheduled for early Oct05 Semester.

Backends

The Multibeam correlator samplers have been upgraded to provide 4- and 8-MHz bandwidths for all 13 beams of the multibeam receiver. Previously these bandwidths were available only for the seven inner beams. This project was carried through very ably by Tim Ruckley and Mark Leach. Along the way they found the cause of, and solved, a long-standing niggling problem of low-level "birdies" in the multibeam spectra.

A significant increase in the power and flexibility of the multibeam correlator has been realised by co-locating the system with the Wideband (pulsar) correlator in the upstairs control room. This integration of the two correlators was prompted in the first instance by the advent of a major new project, the Galactic All Sky Survey (GASS). This project is now observing in a configuration with 13 beams × 2048 spectral channels × 2 polarisations (8-MHz bandwidth), which was not possible before the recent changes. Many other "hybrid" correlator modes are now possible. The changes also allow the possibility of providing the multibeam sampler outputs to "3rd party" devices.

The relocation and merging of the two correlators was "fast tracked" for the GASS project, and was made possible by the tireless cogitations and exertions of many ATNF staff over the last two months, particularly Warwick Wilson, Tim Ruckley, Brett Preisig and Barry Turner.

Interference mitigation

The old microwave tower to the East of the 64-m dish, formerly used in the microwave link to Tidbinbilla, has a new lease on life. The original 3-m dish on this tower has been redeployed to receive TV transmissions in the 50-cm band from Mt Ulandra, 200 km to the South. The excellent reception (or perniciously strong reception, depending on your point of view!) has provided a much superior template of these interfering signals, greatly enhancing the efficiency of the proposed active-cancellation schemes. The system uses the feed from the older 50-cm receiver (used prior to the 10/50-cm receiver).

Site changes

New changes are evident daily at the Observers Quarters as work progresses rapidly on the building of a new kitchen wing. The concrete slab was poured in December, framework was erected in early January and work on the new roof line was progressing well at the end of January. The work occasionally causes disruptions for visitors to the Observatory – and for Quarters staff – for which we apologise. However, the end result will be a vastly improved kitchen and upgraded dining area which will improve facilities for all visitors for many years to come.

Work on the major upgrade of the worst section of the six-km road to the site started in November and was scheduled for completion by mid-December. The upgrade is jointly funded by CSIRO and the Parkes Shire Council and the Council is carrying out the work. Rain and a problem with the supply of gravel needed for the significant widening and raising of the road foundation have delayed progress considerably. The foundation of the first 2-km section of the works was nearly ready for sealing at the end of January, and progress on the remainder will follow immediately.

John Reynolds
Officer-in-Charge, Parkes Observatory
(John.Reynolds@csiro.au)