Studies the global structure of the Milky Way (bulge, bar, disk, spiral arms) using infrared and radio observations of stars and gas, and the evolution of galaxy groups via radio observations.

Radio astronomer working on very-long-baseline interferometry (VLBI) and radio imaging instrumentation, including maser and stellar-envelope studies and computational methods for radio astronomy.

Directs the Laboratory for Astronomical Imaging; develops millimeter/submillimeter interferometric imaging instrumentation (e.g., for ALMA) and studies star and protoplanetary disk formation.

Studies the interstellar and intergalactic medium and galaxy evolution via radio observations of neutral hydrogen and molecular gas.

Studies molecular gas and the interstellar medium in galaxies using radio and millimeter interferometry (e.g., ALMA, CARMA).