Acta Geodaetica et Geophysica

, Volume 49, Issue 3, pp 313–325 | Cite as

Importance of the Hartebeesthoek Radio Astronomy Observatory for the VLBI network

  • D. Mayer
  • J. Böhm
  • L. Combrinck
  • J. Botai
  • S. Böhm


The Hartebeesthoek Radio Astronomy Observatory (HartRAO) is the only very long baseline interferometry (VLBI) station in Africa, its importance to the current and future network is discussed in the presented analysis. In order to quantify the contribution of the HartRAO station to VLBI products, different approaches (e.g. comparison of number of observations to sources, formal errors of EOP and baseline length repeatabilities) are analysed. Two datasets were used, CONT08 and IVS-R1 sessions from the years 2011 and 2012. The results suggest that the station is of high importance to the current and future global VLBI network. In particular, HartRAO is crucial for maintaining the ICRF on the Southern Hemisphere; it is also one of the most important stations for the estimation of polar motion and nutation (e.g. when HartRAO is excluded from different networks the formal error of nutation increases by about 50 %). The quality of the station coordinates of remote southern stations such as TIGOCONC is also heavily dependent on HartRAO.





The authors would like to thank the Hartebeesthoek Radio Astronomy Observatory and the Vienna University of Technology for providing financial support for this work, as well as the University of Pretoria for providing facilities and assistance. David Mayer and Johannes Böhm are grateful to the Austrian Science Fund (FWF) for supporting project P23143-N21 (”Integrated VLBI”).


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Copyright information

© Akadémiai Kiadó 2014

Authors and Affiliations

  • D. Mayer
    • 1
  • J. Böhm
    • 1
  • L. Combrinck
    • 2
    • 3
  • J. Botai
    • 3
  • S. Böhm
    • 1
  1. 1.Vienna University of TechnologyViennaAustria
  2. 2.Hartebeesthoek Radio Astronomy ObservatoryKrugersdorpSouth Africa
  3. 3.Department of Geography, Geoinformatics & MeteorologyUniversity of PretoriaPretoriaSouth Africa

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