A new website has been launched to explain the importance of very long-baseline interferometry (VLBI) to geodesy and the wider geospatial community. The resource serves as a tool for basic geodetic knowledge and aims to clarify concepts such as geodesy and the International Terrestrial Reference Frame for non-specialists.
The website provides details on VLBI's operational mechanisms, its significance for scientists, engineers, and society, and the processes involved in data production and processing. It also highlights Australia's role within the global VLBI network.
Australia operates three VLBI stations, located near Hobart, Katherine, and Yarragadee in Western Australia, which constitute the AuScope VLBI Array. These telescopes conduct multiple geodetic observation sessions each week. In 2025, Australian telescopes are projected to participate in approximately 90% of all international geodetic VLBI experiments.
These three Australian telescopes rank among the top 15 radio telescopes globally for total observing hours in 2025, with each performing between 3,000 and 4,000 hours of observations annually. This high level of activity is attributed to Australia's expertise in the field and the strategic geographic placement of the Array's telescopes in the Southern Hemisphere.
Data collected by the Australian network is processed by a 'correlator' hosted on the Gadi supercomputer in Canberra, which is part of the National Computational Infrastructure. Up to one petabyte of data is allocated for this processing.
Additional topics covered on the website include the International Celestial Reference Frame, Earth orientation parameters, the International VLBI Service for Geodesy & Astrometry, and active galactic nuclei, which are central to the observation efforts.
The website was developed by Dr. David Schunck and Dr. Lucia McCallum from the geodetic VLBI research group at the University of Tasmania (UTAS). This initiative is part of an AuScope communication project, conducted in collaboration with Geoscience Australia and UTAS.