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The primary aim is to establish a firm value for the distance to theextraordinary planetary nebula KjPn 8. Secondary aims are to measure the agesof the three giant lobes of this object as well as estimate the energy in theeruption, that caused the most energetic outflow, for comparison with that ofan intermediate luminosity optical transient (ILOT). For these purposes amosaic of images in the Halpha+[N II] optical emission lines has been obtainedwith the new Aristarchos telescope in 2011 for comparison with the images ofthe KjPn 8 giant lobes present on the POSSI-R 1954 and POSSII-R 1991 plates.Expansion proper motions of features over this 57 yr baseline in the outflowsare present. Using these, a firm distance to KjPn 8 of 1.8 +- 0.3 kpc has beenderived for now the angle of the latest outflow to the sky has been establishedfrom HST imagery of the nebular core. Previously, the uncertain predictions ofa bow-shock model were used for this purpose. The dynamical ages of the threeseparate outflows that form the giant lobes of KjPn 8 are also directlymeasured as 3200, 7200 and >= 5x10^4 yr respectively which confirms theirsequential ejection. Moreover, the kinetic energy of the youngest and mostenergetic of these is measured as ~10^47 erg which is compatible with an ILOTorigin.

The expansion proper motions of the extraordinary giant lobes of the planetary nebula KjPn 8 revisited