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The existence of a vast nova shell surrounding the prototypical dwarf nova ZCamelopardalis (Z Cam) proves that some old novae undergo metamorphosis toappear as dwarf novae thousands of years after a nova eruption. The expansionrates of ancient nova shells offer a way to constrain both the time betweennova eruptions and the time for post-nova mass transfer rates to decreasesignificantly, simultaneously testing nova thermonuclear runaway models andhibernation theory. Previous limits on the expansion rate of part of the Z Camshell constrain the inter-eruption time between Z Cam nova events to be $>$1300 years. Deeper narrow-band imaging of the ejecta of Z Cam with the CondorArray Telescope now reveals very low surface brightness areas of the remainderof the shell. A second, even fainter shell is also detected, concentric withand nearly three times the size of the "inner" shell. This is the firstobservational support of the prediction that concentric shells must surroundthe frequently-erupting novae of relatively massive white dwarfs. The Condorimages extend our Z Cam imaging baseline to 15 years, yielding the innershell's expansion rate as $v = 83 \pm 37$ km s$^{-1}$ at 23 degrees South ofWest, in excellent agreement with our 2012 prediction. This velocitycorresponds to an approximate age of $t = 2672^{-817}_{+2102}$ yr. Whileconsistent with the suggestion that the most recent nova eruption of Z Cam wasthe transient recorded by Chinese Imperial astrologers in the year 77 BCE, theage uncertainty is still too large to support or disprove a connection with ZCam.

Introducing the Condor Array Telescope: III. The expansion and age of  the shell of the dwarf nova Z Camelopardalis, and detection of a second,  larger shell