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IRAS 20126+4104 is one of the best candidates for a high-mass (proto)starsurrounded by an accretion disk. Such a fact may be used to set constraints ontheories of high-mass star formation, but requires confirmation that the massand luminosity of IRAS 20126+4104 are indeed typical of a B0.5 star, which inturn requires an accurate estimate of the distance. We used the Very LongBaseline Array and the European VLBI Network to observe the 22.2 GHz water and6.7 GHz methanol masers in IRAS 20126+4104 at a number of epochs suitablydistributed in time. The absolute positions of the maser features wereestablished with respect to reference quasars, which allowed us to deriveabsolute proper motions. From the parallax of the water masers we obtain adistance of 1.64 \pm 0.05 kpc, which is very similar to the value adopted sofar in the literature (1.7 kpc) and confirms that IRAS 20126+4104 is ahigh-mass (proto)star. From the methanol masers we derive the component in theplane of the sky of the systemic velocity of the disk+star system (-16 km/s inright-ascension and +7.6 km/s in declination). Accurate knowledge of thedistance and systemic velocity allows us to improve on the model fit to thewater maser jet presented in a previous study. Finally, we identify two groupsof methanol maser features, one undergoing rotation in the disk and possiblydistributed along a narrow ring centered on the star, the other characterisedby relative proper motions indicating that the features are moving away fromthe disk, perpendicular to it. We speculate that the latter group might betracing the disk material marginally entrained by the jet.

Methanol and water masers in IRAS 20126+4104: The distance, the disk, and the jet