9307913 Backer Studies of Compact Galactic Objects. The three goals of Dr. Backer's research are (a) an exploration of the use of an array of millisecond pulsars as a celestial clock ensemble; (b) a broader understanding of interstellar microturbulence which affects radio signal propagation; and (c) a more complete view of the radiation mechanism and underlying dynamics in active galactic nuclei with a focus on our galactic center. Dr. Backer will carry out a variety of observational programs at radio wavelengths with related analysis and interpretation. The observational programs will be advanced by instrumentation developed and maintained by Dr. Backer, and used primarily at the National Observatories.