  We performed VLA observations of the 22 GHz H2O maser emission in the merging
galaxy NGC6240, which hosts the well-known double active nuclei. In a previous
paper, we reported on the first solid detection of the H2O maser emission in
2001. After two abortive attempts due to the weakness and probable variability
of the emission, the maser was detected with the VLA in June 2002. The emission
is unresolved at ~ 0.3 arcsecond and coincides with the southern 22 GHz
continuum peak to ~ 0.007 arcsecond (~ 3 pc: D = 97 Mpc). The detection of the
maser in the southern nucleus indicates that nuclear activity of the
galaxy,which is significant in X-ray and far-infrared (FIR) bands, lies mainly
in the southern nucleus, and the nucleus without a high brightness peak could
be explained by thick dust emitting FIR radiation. We favour the idea that the
maser in NGC6240 is associated with the AGN-activity.
