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Type Ia supernovae (SN Ia) have enormous importance to cosmology and astrophysics comma but their progenitors and explosion mechanisms are not understood in detail. Recently comma observations and theoretical models have suggested that not all thermonuclear white-dwarf supernova explosions are normal SN Ia. In particular comma type Iax supernovae (SN Iax comma peculiar cousins to SN Ia) comma are thought to be exploding white dwarfs that are not completely disrupted comma leaving behind a bound remnant. We propose late-time HST WFC3 observations of three recent SN Iax to directly observe if they each harbor a bound remnant comma with a radiation-driven wind. Our program is designed to discover a new category of stars comma powered by radioactivity comma and to show that some thermonuclear supernovae are not terminal events in the life of their progenitor white dwarfs (unlike the complete disruption thought to occur in normal SN Ia).