  Decoherence affects all quantum systems, natural or artificial, and is the
primary obstacle impeding quantum technologies. We show theoretically that for
a Rydberg qubit in a Bose condensed environment, experiments can image the
system-environment interface that is central for decoherence. High precision
absorption images of the condensed environment will be able to capture
transient signals that show the real time build up of a mesoscopic entangled
state in the environment. This is possible before decoherence sources other
than the condensate itself can kick in, since qubit decoherence time-scales can
be tuned from the order of nanoseconds to microseconds by choice of the excited
Rydberg principal quantum number {\nu}. Imaging the interface will allow
detailed explorations of open quantum system concepts and may offer guidance
for coherence protection in challenging scenarios with non-Markovian
environments.
