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• Space-VLBI phase-reference mapping and astrometry,
  J.C. Guirado, E. Ros, D.L. Jones, J.-F. Lestrade, J.M. Marcaide, M.A. Pérez-Torres, & R.A. Preston
  Astronomy & Astrophysics, 371:766-771 (2001)
  
  • Abstract We present 5GHz space-vlbi observations of the quasar pair B 1342+662/B 1342+663 that demonstrate the feasibility of phase-reference techniques using an antenna in space. The space-based data were taken by the spacecraft HALCA, of the space-VLBI mission VSOP. From residual (referenced) phases we derive an upper bound of 10 meters to the uncertainty of the spacecraft orbit reconstruction. An analysis of the phase-reference maps of thes sources additionally suggests that the above mentioned uncertainty is very likely not larger than 10 meters. With errors of such magnitude, HALCA is a useful tool for astrometric studies of close pairs of radio sources.

Eduardo Ros ros@mpifr-bonn.mpg.de

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