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We present observational results of water vapor maser emission with our high-sensitivity 22 GHz very long baseline interferometry (VLBI) imaging of the Seyfert galaxy NGC 1068. In this galaxy, there are the following four nuclear radio sources; NE, C, S1, and S2. Among them, the S1 component has been identified as the nucleus while the C component has been considered as attributed to the radio jet. In our VLBI observation, we find the following two types of water maser emission at the S1 component. One is a linearly aligned component that is considered as an edge-on disk with an inner radius of 0.62 pc. The dynamical mass enclosed within the inner radius was estimated to be 1.5 × 107  M ⊙ by assuming the circular Keplerian motion. Note, however, that the best-fitting rotation curve shows a sub-Keplerian rotation (v ∝ r −0.24±0.10). The other is water maser emission distributed around the rotating disk component up to 1.5 pc from the S1 component, suggesting a bipolar outflow from the S1 component. Further, we detected water maser emission in the C component for the first time with VLBI, and discovered a ring-like distribution of water maser emission. It is known that a molecular cloud is associated with the C component (both HCN and HCO+ emission lines are detected by ALMA). Therefore, the ring-like maser emission can be explained by the jet collision to the molecular cloud. However, if these ring-like water masing clouds constitute a rotating ring around the C component, it is likely that the C component also has a supermassive black hole with a mass of ∼106  M ⊙ that could be supplied from a past minor merger of a nucleated satellite galaxy. [ABSTRACT FROM AUTHOR]

Water vapor maser emission from a Seyfert 2 galaxy IC2560 was observed with sensitive VLBI. The accurate black hole mass was determined by separating the mass of the disk surrounding the black hole. In addition, the distance of the galaxy was directly measured from the maser disk. The Hubble constant determined using the distances and recession velocities of IC2560 and othere megamasers is inconsistent with that determined with CMB by 3–6 km s-1 Mpc-1. [ABSTRACT FROM AUTHOR]

VERA has been regularly conducting astrometry of Galactic maser sources for ∼ 20 years, producing more than 100 measurements of parallaxes and proper motions of star-forming regions as well as AGB stars. By combining the observational results obtained by VLBA BeSSeL, EVN, and LBA, maser astrometry provides a unique opportunity to explore the fundamental structure of the Galaxy. Here we present the view of the Galaxy revealed by the maser astrometry, and also discuss the importance of maser astrometry in the era of GAIA by comparing the results obtained by VLBI and GAIA. We also present our view of "proper motions toward the future" of the relevant field, expected in the next decade based on global collaborations. [ABSTRACT FROM AUTHOR]

We will report the activities of the VERA single-dish observations. We are carrying out single-dish observations with two purposes. The first purpose is the monitoring of known H2O maser sources. At present, we are carrying out monitoring observations for 312 H2O maser sources at intervals of two months. The second purpose is the search for new water maser sources. We selected 901 target sources from the AKARI FIS Bright Source Catalogue. We found 61 new H2O maser sources. [ABSTRACT FROM AUTHOR]