The Carina dSph galaxy: where is the edge?

Recent cosmological N-body simulations suggest that current empirical esti- mates of tidal radii in dSphs might be underestimated by at least one order of magnitude. To constrain the plausibility of this theoretical framework, we undertook a multiband (U,B,V,I) survey of the Carina dSph. Deep B,V data of several fields located at radial distances from the Carina center ranging from 0.5 to 4.5 degrees show a sizable sample of faint blue objects with the same magnitudes and colors of old, Turn-O stars detected across the center. We found that the (U-V,B-I) color-color plane is a robust diagnostic to split stars from back- ground galaxies. Unfortunately, current U,I-band data are too shallow to firmly constrain the real extent of Carina.