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The data release 1 (DR1) of milliarcsecond-scale accurate optical positionsof stars and galaxies was recently published by the space mission Gaia. Westudy the offsets of highly accurate absolute radio (very long baselineinterferometry, VLBI) and optical positions of active galactic nuclei (AGN) tosee whether or not a signature of wavelength-dependent parsec-scale structurecan be seen. We analyzed VLBI and Gaia positions and determined the directionof jets in 2957 AGNs from their VLBI images. We find that there is astatistically significant excess of sources with VLBI-to-Gaia position offsetin directions along and opposite to the jet. Offsets along the jet vary fromzero to tens of mas. Offsets in the opposite direction do not exceed 3 mas. Thepresense of strong, extended parsec-scale optical jet structures in many AGNsis required to explain all observed VLBI-Gaia offsets along the jet direction.The offsets in the opposite direction shorter than 1 mas can be explainedeither by a non-point-like VLBI jet structure or a "core-shift" effect due tosynchrotron opacity.

VLBI-Gaia offsets favor parsec-scale jet direction in Active Galactic Nuclei