  We report the discovery of an extensive system of scattered light echo
arclets associated with the recent supernovae in the local neighbourhood of the
Milky Way: Tycho (SN 1572) and Cassiopeia A. Existing work suggests that the
Tycho SN was a thermonuclear explosion while the Cas A supernova was a core
collapse explosion. Precise classifications according to modern nomenclature
require spectra of the outburst light. In the case of ancient SNe, this can
only be done with spectroscopy of their light echo, where the discovery of the
light echoes from the outburst light is the first step. Adjacent light echo
positions suggest that Cas A and Tycho may share common scattering dust
structures. If so, it is possible to measure precise distances between
historical Galactic supernovae. On-going surveys that alert on the development
of bright scattered-light echo features have the potential to reveal detailed
spectroscopic information for many recent Galactic supernovae, both directly
visible and obscured by dust in the Galactic plane.
