  Eta Carinae, the closest, active, massive binary containing a highly unstable
LBV, exhibits expanding, compressed wind shells, seen in emission, that are
spatially and spectrally resolved by \hst/\stis. Starting in June 2009, these
structures were mapped across its 5.54-year, highly elliptical, binary orbit to
follow temporal changes in the light of [Fe~III] 4659\AA\ and [Fe~II] 4815\AA.
The emissions trace portions of fossil wind-shells, that were formed by
wind-wind interactions across each cycle. Over the high-ionization state, dense
arcs, photo-ionized by far ultraviolet radiation from the hot secondary, are
seen in [Fe~III]. Other arcs, ionized by mid-ultraviolet radiation from the
primary star, are seen in [Fe II]. The [Fe III] structures tend to be interior
to [Fe II] structures that trace extensive, less disturbed primary wind. During
the brief periastron passage when the secondary plunges deep into the primary's
extremely dense wind, on the far side of primary star, high-ionization [Fe III]
structures fade and reappear in [Fe II]. Multiple fossil wind-structures were
traced across the 5.7-year monitoring interval. The strong similarity of the
expanding [Fe II] shells suggests that the wind and photo-ionization properties
of the massive binary have not changed substantially from one orbit to the next
over the past several orbital cycles. These observations trace structures that
can be used to test three-dimensional hydrodynamical and radiative-transfer
models of massive, interacting winds. They also provide a baseline for
following future changes in Eta Carinae, especially of its winds and
photoionization properties.
