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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. Perez-Torres·R. A. Preston
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Abstract

We present 5 GHz space-VLBI observations of the quasar pair B1342+662/B1342+663 that demonstrate the feasibility of phase-reference techniques using an antenna in space. The space-based data were taken by the satellite 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 the sources additionally suggests that the above mentioned uncertaintyis likely not larger than 3 meters. With errors of this magnitude, HALCA is a useful tool for astrometric studies of close pairs of radio sources.

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J. C. Guirado, E. Ros, D. L. Jones, J. F. Lestrade, J. M. Marcaide, M. A. Perez-Torres, R. A. Preston. 2001-04-23. Space-VLBI phase-reference mapping and astrometry. https://doi.org/10.1051/0004-6361%3A20010370

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