Paper: Disk Structure of the H_2O Maser IC 1396N Volume: 144, Radio Emission from Galactic and Extragalactic Compact Sources, IAU Colloquium 164 Page: 365 Authors: Val'tts, I. E.; Slysh, V. I.; Migenes, V.; Umemoto, T.; Furuya, R.; Kawabe, R.; Fomalont, E. B.; Hirabayashi, H.; Inoue, M. Abstract: The VLBA map of the H\$_2\$O maser IC 1396N, which was obtained during the VSOP pre-launch survey, shows an ordered position of maser spots. The maser spots are located along an almost straight line with the separation between extreme maser spots of 20 mas. The radial velocity varies along the line from by 3 km s^{-1}. In total 9 maser features have been located on the line, all of them unresolved by the VLBA beam. This geometry is consistent with the disk model of masers. The mass of the disk is estimated between 10^{-7} and 10^{-4} M_\odot, depending on the thickness and density. The disk must be supported by a central star with the mass of about 0.07 M_\odot. The H_2O maser in IC 1396N may be a proto-planetary disk around a low mass protostar in the process of accretion.