Light Echoes in Type Ia Supernovae
  Light echoes are a promising tool to probe the environment where SNe Ia explode and an independent source of information on the progenitor's nature. After giving a brief introduction to the phenomenon we review the two known cases, i.e. SNe 1991T and 1998bu. We then present the results we obtained from the test case of SN1998es in NGC632. This object was classified as a 1991T-like event and was affected by a strong reddening, a fact which made it a good candidate for a light echo detection. 
Ferdinando Patat