Avruch 9802463 This award supports a 12 month Japan Society for the Promotion of Science (JSPS) Postdoctoral Fellowship for Dr. Ian Avruch at the Institute of Space and Astronautical Science (ISAS), Sagamihara, Japan. Dr. Avruch will work with Dr. Hirabayashi, VSOP Mission Project Scientist, ISAS, on a research project entitled, "Space Very-Long-Baseline Interferometry with the HALCA Satellite and the VSOP Program." The proposed research project will make use of a new capability in radio astronomy, the HALCA satellite, a project of ISAS with significant participation by NASA. The general scientific goals of the mission include performing the highest resolution observations of the cores of Active Galactic Nuclei (AGN), monitoring superluminal structures in AGN, and determining distances to galaxies by the motions of their water masers. The established technique of Very-Long- Baseline Interferometry employs fixed radio telescopes around the earth observing a celestial object simultaneously, each writing data to high density storage media. Interferometric baselines as long as an earth diameter can be formed when the data are brought together and reduced appropriately; the angular resolution on the sky approaches that of an equivalent single antenna the size of the earth. The HALCA satellite is an orbiting radio telescope that extends baselines up to three earth radii, for a resolution of 55 microarcseconds. ***
