T. L. Duvall Jr., A. G. Kosovichev, and P. H. Scherrer Sunspots: Frontside and Backside Measurements with Time-Distance Helioseismology In time-distance helioseismology, travel times measured between different surface locations are used to infer subsurface flows, temperature inhomogeneities and magnetic fields. It has been suggested that most of the travel time reduction near sunspots may be due to the lowered reflection layer associated with the Wilson depression. This will be examined by looking at rays that travel below the sunspot but do not begin or end in the spot. A time-distance method of imaging sunspots on the backside will be compared with that of Lindsey and Braun.