MERLIN 6-GHz maser emission from W3(OH)

We present the preliminary results of the first alignment to milliarsecond accuracy of the 6 GHz maser emission in OH and methanol maser lines toward W3(OH). The identifications of Zeeman pairs allowed us to infer the actual velocity of the OH material and the magnetic field strength at the location where 6.7 GHz methanol maser emission arises.