view Abstract Citations (17) References (14) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Extending the Very Long Baseline Interferometry Celestial Reference Frame to the Southern Hemisphere Robertson, D. S. ; Carter, W. E. ; Ray, J. R. ; Dillinger, W. H. ; Nicolson, G. D. ; McCulloch, P. D. ; Hamilton, P. A. ; Seeger, H. Abstract Geodetic very long baseline interferometry measurements have been extended to the southern hemisphere using stations in South Africa, Tasmania, and Chile. These measurements enabled us to add a number of southern hemisphere radio sources to the catalog that defines our celestial reference frame. Positions have been determined for 81 radio sources ranging in declination from 78^deg^ N to 80^deg^ S with formal errors of a few tenths of a millisecond of arc. Numerical experiments to determine the sensitivity of the estimated positions to systematic error sources such as atmospheric refraction variations indicate that they are roughly comparable in magnitude to the formal errors. Preliminary measurements of the total and correlated source flux densities at 2.3 and 8.4 GHz are presented for a subset of the sources in the southern hemisphere. Publication: The Astronomical Journal Pub Date: January 1993 DOI: 10.1086/116434 Bibcode: 1993AJ....105..353R Keywords: Radio Sources (Astronomy); Reference Systems; Southern Sky; Very Long Base Interferometry; Astronomical Catalogs; Celestial Geodesy; Nasa Programs; Southern Hemisphere; Astronomy; REFERENCE SYSTEMS; TECHNIQUES: INTERFEROMETRIC full text sources ADS | data products NED (81) SIMBAD (79)